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Azra NMBAL

water is life. I will throw this word out because if a person is dehydrated for 3 days, he will die, but he can live without eating for 1 month. water is very important not only for our life but also for other living things.

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Water is one of our sources of life as our blood is made of 85% water.
And humanity can only create large cities if there is a large source of drinking water nearby, it can only make huge plantations due to "rivers of water".
We can survive 3 minutes without oxygen, 3 days without water and 3 weeks without food.

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Water is important for living beings because without water we wouldn't live. Living beings are made up of 70% to 95% water
If a human being doesn't drink water he/she can die from dehydration.

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Water is important for living beings because ... without water we, humans and animals, would not survive because we would die of dehydration. We would not be able to have agriculture or livestock to have food to eat.

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Water is very important, for the survival of all living beings, because without it nobody survives, every day, water has become more important, because for everything we need it, for industry, for agriculture and essentially to survive. An average human being can go 3 weeks without eating, but only 3 days without drinking water.

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I think that we, living beings,  need and can only survive if there is water. Water is not only needed for drinking, we need it to be able to bathe and water the plants and to the balance of all ecosystems.
 Fish and all sea life also need water to be able to live.
So I think that water is very important for all living beings.

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People use water in agriculture to grow important plants, crops or to sustain animals with it. If there was no water, there would be no food or animals.

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Water is life, basically.
Our body is made up of 70% of water and we need water to survive and to have a good and long life.
We need water for everything , like vegetables, so we can eat them later, for the animals and for other many important things.
So water is very important for us but nowadays we need to take some care because it is in danger of depletion, and if the water runs out , our lives will end as well as all other lives.

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Water is important for living beings because since our existence has begun, all living beings need water, some more than others. Water is important in in our lives, not just for living beings but also for a lot of other things such as flexibility and efficiency. Water has a lot of strengths and it's our duty to protect this resource  mainly from pollution.

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Water is important for living beings because all living beings need water to stay hydrated. Drinking water is becoming less drinkable as we are polluting it, but we need to preserve it. We must protect it carefully because there is only 3% of potable water.Water is a rich source of mineral salts and all living beings need to drink it and need it to survive in a healthy ecosystem. We use water for many day-to-day needs.

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Water is too important in our lives.
Every living organism needs water to be
alive and it is also good to keep people hydrated and maintaining bodily functions.
It is good for your health for obvious reasons.
We use water everyday for our hygiene, for cooking, watering plants or even cleaning.
Also, a lot of animals live in water so they need it to not only live but also to sail, swim...

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The first living creatures emerged in water fed on organic substances that had formed during a slow process of chemical evolution on our planet. Nowadays we keep using water in our lives everyday. We use water to drink,to cook, in the clothing industry, to do basically everything. Water is the basic substance of life, in our planet we can find water in 3 different forms: solid, gaseous and liquid. In these three we can find different animal species. To conclude, we can say that water is the most important source for us, human beings, whose body is made up of 73% of water and for other animal species that use water to live.

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Water is vital for the survival of living things. From the smallest living organism to the largest living being, it is water that sustains all biological life and all human activities. Covering 70% of our world, water also constitutes an important part of our body. However, about 0.3% of the water resources on earth are usable and drinkable.

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Water is important for living beings, because all living beings need water to survive and since 73% of the human body is composed by water, it basically acts as an essential source of energy for the health of the human body and living beings.

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What would happen if you didn’t drink water? - Mia Nacamulli

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Water is important for living beings. Water based organisms such as fish require water to breathe. Without a water supply, they could not access oxygen and would suffocate.

Here's a video of why fish need water:

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Why Fish Need Water.  (Cowichan Watershed Board. July 2020)

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Living beings need water to survive, not only for reasons of hydration but also for daily tasks such as washing dishes or bathing. It can also be used in other ways such as agriculture. Unfortunately humans are destroying/polluting this resource that it is so essential for us.

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Water is important for the life of all living beings, so that they can grow and develop every day in a healthy way.

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Why Do We Drink Water? | Importance Of Water | Stay Hydrated | The Dr Binocs Show | Peekaboo Kidz

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We drink water on a daily basis. 73% of our body is composed by water.
Without water our body wouldn't work how it's supposed.
Our brain needs water to produce hormones and neurotransmitters.

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Water is important for all the living organisms because we all need it for survival. For a proper life, we need access to water every day as we use it in the food idustry, agriculture, transportation, recreation and it makes up about 70% of our bodies. However, only about 1% of all the water in the world is fresh water and today, we are also using our water that was intended for tomorrow. We are spending too much of it. Now is our time in history to individually save and protect this magical liquid.

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Water is important for all living organisms because it is the way of our survival. Without water nothing would be able to live.

We do not need water only for drinking and showering. Water is important in many ways.

So much water goes to making clothes. It is insane how much water we need to use. For an example we need about 1,800 gallons of water to make the cotton in a pair of jeans.

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The Global Water Crisis | How Much Water Do We Really Use Everyday? | TakePart

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For decades scientists have been trying to prove that we need to start to care about water more, because many of us consider it as a common thing and don't realise that we would die without clean and safe water. However, for some people it's a treasure to have it and they have serious diseases because they can't get safe and drinkable water. We use water everyday in cooking, for our basic hygiene and also for watering our plants. There are million other uses of it since every living organism here on Earth needs it.

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Water is important for all living organisms because it breaks down the food you eat, allowing its nutrients to be absorbed by your body.

It delivers oxygen throughout the body. Blood is more than 90 percent water, and blood carries oxygen to different parts of the body.

It boosts skin health and beauty. With dehydration, the skin can become more vulnerable to skin disorders and premature wrinkling.

It helps maintain blood pressure. A lack of water can cause blood to become thicker, increasing blood pressure.

It forms saliva and mucus. Saliva helps us digest our food and keeps the mouth, nose, and eyes moist. This prevents friction and damage. Drinking water also keeps the mouth clean.

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Scientific research shows that your body uses water in all its cells, organs, and tissues to help regulate temperature and maintain other critical functions for survival. Discover the importance of water in this detailed article.

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We would not be here if it did not exist. The first organisms/first sign of life appeared in the water. It all started there.

70% of our bodies are made of water. We drink it, we clean with it, we cook with it, we use it to create new materials. Many people does not realize that we should take care of our water, we cannot waste it,  because one day it is possible that thanks to human ignorance we will not have drinking water. What would we do?

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Water is important for all living organisms because they need it to hydrate their body. Chemical reactions in the body take place in water. Blood is 90% water. Water also carries nutrients to different parts of the body. It also removes waste products from the body. It regulates our body temperature. Plants also need water. They cannot produce food without it. Moreover, a lot of animals live in the water.

We use water in our everyday life. For example, when we cook, shower, or clean our house. It is essential for all living things. So, we should not waste it.

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Food and Agriculture Organization of the United Nations

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World Water Day 2021: What does water mean to you?

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Because everyone would be dead in few days if there was none of it left.

We cannot also forget that our body mostly consists of water and also we produce saliva which is, actually, water.

There is also our home planet which mainly consists of water. 71 percent to be precise. And in those waters we can find a lot of living organisms. Some of them are edible and can be food for humans.

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Why Is Water Important? 16 Reasons to Drink Up

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Not only does water make up most of your weight, it’s involved in many important functions. See how water improves your overall well-being.

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Because water covers more than 3 / 4 of the Earth it is essential for all living organisms. For exapmle plants cannot produce food without water, human being consist of 70 percent of water and importance of water is also in food that we consume to be healthy and be able to cleanse our organism. Water is also home for many animals living there that are no table to breathe air.

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These dark, narrow, 100 meter-long streaks (called recurring slope lineae) are flowing downhill on Mars, and are inferred to have been formed by contemporary flowing water. Recently, planetary scientists detected hydrated salts on these slopes at Hale crater, corroborating their original hypothesis that the streaks are indeed formed by liquid water. The blue color seen upslope of the dark streaks are thought not to be related to their formation, but instead are from the presence of the mineral pyroxene.

Credit: NASA/JPL/University of Arizona

Water. It's found everywhere on Earth, from the polar ice caps to steamy geysers. And wherever water flows on this planet, you can be sure to find life.

"When we find water here on Earth - whether it be ice-covered lakes, whether it be deep-sea hydrothermal vents, whether it be arid deserts - if there's any water, we've found microbes that have found a way to make a living there," said Brian Glazer, an oceanographer at the University of Hawaii at Manoa, who has studied astrobiology.

That's why NASA's motto in the hunt for extraterrestrial life has been "follow the water."

Yesterday (Sept. 28), NASA scientists announced they'd found it on Mars: Dark streaks that scientists have spotted seasonally for more than a decade in images of the Red Planet are evidence of flowing water, new research suggests. While the briny flows may be too full of chlorine-based salts to support life, they do raise the odds that Mars could have life right now, the researchers said. [ In Photos: Is Water Flowing on Mars?]

But just why is water such a crucial molecule for life? And could there be other ingredients that also provide the perfect recipe for life on other planets?

It turns out that several chemical properties of water make it indispensable for living creatures. Not only can water dissolve nearly anything, but it is also one of only a few materials that can exist as solid, liquid and gas within a relatively narrow range of temperatures.

Flowing life

At heart, all life on Earth uses a membrane that separates the organism from its environment. To stay alive, the organism takes in important materials for making energy, while shuttling out toxic substances such as waste products.

In this regard, water is essential simply because it's a liquid at Earth-like temperatures. Because it flows, water provides an efficient way to transfer substances from a cell to the cell's environment. By contrast, deriving energy from a solid is a much tougher prospect (though there are microbes that eat rock), Glazer said.

But the other part of the equation - that water can carry things into and out of the cell - has to do with water's unique chemical configuration.

The humble water molecule is made up of two hydrogen atoms bonded to an oxygen atom.

"The way they're bonded together makes water this wonderful universal solvent," meaning that almost every substance can dissolve in water, Glazer told Live Science.

That's because the molecule has polarity, meaning the hydrogen atoms tend to bunch on one side of the molecule, creating a positive region, while the oxygen end has a negative charge. The positive hydrogen end tends to attract negative ions (or atoms with an extra electron in the outer shell), while the negative region lures in positive ions (which have had one of their electrons stripped off).

Water, with its amazing dissolving properties, is the perfect medium for transmitting substances, such as phosphates or calcium ions, into and out of a cell.

Phases of water

Another feature of water is that it can act as a solid, liquid and gas within the range of temperatures that occur on Earth. Other molecules that have been identified as good candidates for supporting life tend to be liquid at temperatures or pressures that would be inhospitable for most known life-forms, Glazer said. [ 5 Mars Myths and Misconceptions]

"Water really is at that sweet spot," Glazer said.

The fact that water can be in all three phases in a relatively tight range of pressures creates many opportunities for life to flourish, he added.

"All three [states of water] available on our planet creates this really neat variety of habitats and microclimates," Glazer said.

For instance, frozen ice can be found in glaciers that carve through mountains, whereas water vapor helps warm the atmosphere, Glazer said.

Watery cradle of life

Water may be more than a fluid to help facilitate life's essential processes - it may also have been the protective cradle that carried the building blocks of life to Earth, said Ralf Kaiser, a physical experimental chemist at the University of Hawaii at Manoa, who has research experience in astrochemistry.

One theory for how life on Earth emerged, called panspermia, posits that icy comets smashed into Earth, bearing tiny organic molecules that formed the precursors to life. But traveling through space is a harsh journey, with punishing levels of radiation that would normally degrade those delicate molecules, Kaiser said.

However, in its solid form, water could have provided a way to shield those molecules from radiation, Kasier speculated.

"One possibility is that because the building blocks are frozen within the water, it has this protective mantle around it that could be delivered," Kaiser told Live Science.

Accept some substitutes

Of course, while water is crucial to life on our home planet, there could be life-forms that don't conform to the Earthling playbook.

Scientists are also looking at other liquids that could play a similar role as universal solvent and transport medium. Some of the top contenders are ammonia and methane, said Chris McKay, an astrobiologist at the NASA Ames Research Center in Moffett Field, California. Ammonia, like water, is a polar molecule that is relatively abundant in the universe, but scientists haven't found any large bodies of ammonia anywhere in the solar system, McKay said.

Methane isn't polar, but it can dissolve many other substances. Unlike water, however, methane becomes liquid only at very cold temperatures - at a frigid minus 296 degrees Fahrenheit (minus 182 degrees Celsius).

"We know that there are large lakes of liquid methane and ethane on Titan," one of the moons of Saturn, McKay told Live Science in an email. "Thus there is keen interest is the question of whether life can use liquid methane/ethane."

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Water. It's found everywhere on Earth, from the polar ice caps to steamy geysers. And wherever water flows on this planet, you can be sure to find life.

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… it allows everything inside cells to have the right shape

…it allows the outer membranes of cells to have the right shape

…no other molecule matches water when it comes to special properties that support life

…it can dissolve most of biologically needed molecules

…it is an important component of photosynthesis, which keeps plants alive and creates oxygen for us to breathe

…there would be no life without it

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Easy Biology Class | Free Online Biology Tutorials, Lecture Notes & Videos for Life Science Students & Teachers

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Water is the mother liquid of all forms of life. The essentiality of water for living systems is quite evident as without water, there is no life. No other substance on earth is abundant as water. All aspects of cell structure and functions are adapted to the physical and chemical properties of water. The following are the important biological significance or importance of water in the living system.

(1). Water is a 'universal solvent'.(2). Water can dissolve most of the biologically important molecules.(3). It is the solvent of life. The life originated in water and adapted to survive only in the presence of water.(4). About 70 to 90% of a cell occupies water.

(5). Water acts as a medium for the diffusion of molecules in the cell.

(6). Osmotic concentration of cell is maintained by water and dissolved solutes.

(7). The turgidity of the cell is maintained by the water.

(8). Translocation of inorganic and organic compounds in the living system takes place through the water.

(9). Carbohydrates, the product of photosynthesis, in plants are transported through the water.

(10). Water is the source of H+ ions for photosynthesis.

(11). Oxygen is released by the hydrolysis of water during photosynthesis.

(12). Water acts as a reactant in the hydrolysis reaction.

(13). Water supports aquatic plants and animals.

(14). Flagellated and ciliated organisms can swim in the water.

(15). Organisms with flagellated gametes require water for their fertilization.

(16). Lower plants such as algae, fungi, Bryophytes and Pteridophytes require the presence of water to complete their fertilization.

(17). Animals with external fertilization such as amphibians require water for completing their fertilization.

(18). Pollination and dispersal of seed in plants can be done through water bodies.

(19). Water cools the body by sweating process.

(20). Transpiration in plants is due to the presence of water.

(21). Transpiration ensures water uptake and transport of minerals in plants.

(22). Transpiration also cools the leaves and makes them stay in the open sunlight.

(23). Seed germination requires water.

(24). The main medium of blood is water (80% of blood is water)

(25). The main medium of lymphatic system is water.

(26). The excretory system in animals operates through the water medium.

(27). Osmoregulation of cell is due to the presence of water.

(28). Water acts as the lubricant in the joints.

(29). Water acts as the hydrostatic skeletons of annelids and worms.

(30). Water forms the fluids such as tears, saliva, mucus and semen.

(31). Water act as a reactant for many biological reactions.

(32). Hydrophilic and hydrophobic interactions of macromolecules permit formation and stabilization of plasma membrane, conformation of proteins.

(33). Ice has less density than liquid water, thus ice float on the water, this floating ice acts as an insulator over the water bodies and protect the aquatic animals from extreme cold conditions.

(34). Water is transparent, thus enable light penetration and ensure the survival of water plants.

(35). Condensation reaction, a common type of reaction in the cells, results in the release of water molecule.

(36). Water can form buffers with acids and bases.

(37). Water protects the cells from temperature fluctuations.

(38). Water is an essential abiological component of the ecosystem.

(39). Due to the high heat capacity, water prevents the effects of temperature fluctuations in the surroundings.

(40). Water has high density than air, this ensures precipitation and raining.

(41). Water can form a colloidal system in the soil with the nutrients and clay particles.

(42). Water has high dielectric constant.

(43). Water slightly expands when they freeze. If water shrinks during freezing, the ice will sink in the water and will destroy the aquatic life in Polar Regions.

(44). Sound waves can travels 4.5 times faster in water than in air, this permit escaping fishes from dangers.

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More Biochemistry Lecture Notes

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Biological Functions of Water (45 Functions) | Easy Biology Class

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Water is the mother liquid of all forms of life. The essentiality of water for living systems is quite evident as without water, there is no life. No other substance on earth is abundant as water. All aspects of cell structure and functions are adapted to the physical and chemical properties of water.

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People are using water on their daily basis for example in their house in their garden but also all companies and industries use a lot of water every day. On the Earth there is only about 2,5 percent of fresh water and most of it is frozen in the ice caps.

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1 | 2

Well, you just might. It sounds so simple. H2O - two parts hydrogen and one part oxygen. This substance also known as water, is one of the most essential elements to health and is so important that your body actually has a specific drought management system in place to prevent dehydration and ensure your survival. Water might be everywhere, but one must never take it for granted.

Water makes up more than two thirds of human body weight, and without water, we would die in a few days. The human brain is made up of 95% water, blood is 82% and lungs 90%. A mere 2% drop in our body's water supply can trigger signs of dehydration: fuzzy short-term memory, trouble with basic math, and difficulty focusing on smaller print, such as a computer screen. (Are you having trouble reading this? Drink up!) Mild dehydration is also one of the most common causes of daytime fatigue. An estimated 75% of Americans have mild, chronic dehydration. Pretty scary statistic for a developed country where water is readily available through the tap or bottle water.

Water is important to the mechanics of the human body. The body cannot work without it, just as a car cannot run without gas and oil, or EV without electricity. In fact, all the cell and organ functions that make up our entire anatomy and physiology depend on water for their functioning.

Water serves as a lubricant to your body
Water serves as a lubricant in digestion and almost all other body processes. The water in our saliva helps facilitate chewing and swallowing, ensuring that food will slide easily down the esophagus. Water also lubricates our joints and cartilages and allows them to (pardon the pun) move more fluidly. When dehydrated, the body rations water away from the joints. Less lubrication equals greater friction and that can cause joint, knee and back pain potentially leading to injuries and arthritis. Even our eyeballs need plenty of lubrication to work well and remain healthy.

Water regulates your body temperature
Our bodies can control over-heating through perspiration from sweat glands in the skin and from evaporation which produces a cooling effect. Blood is also routed into areas close to the surface of the skin where it can be cooled and then carried back to the interior of the body. Conversing in a cold environment, the skin maintains proper body temperature by shunting the blood away from the exterior surface thereby conserving heat within the body. The movement of water within our cellular systems also transports vital blood plasma which is 92% made of water. Blood plasma play a critical role in buffering the body's pH, circulating antibodies from the immune system, and regulating osmotic balance which all helps to maintain proper body temperature. Moreover, dehydration limits cardiovascular and thermoregulatory responses. This could lead to an increase of core temperature.

1 | 2

Read Next: Are You Drinking Enough Water?

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Importance of water and human health | APEC Water

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1 | 2 Well, you just might. It sounds so simple. H2O - two parts hydrogen and one part oxygen. This substance also known as water, is one of the most essential elements to health and is so important that your body actually has a specific drought management system in place to prevent dehydration and ensure your survival.

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"Water is important for all living organisms because water helps them in the process of breathing, some can even breathe only water. Water helps dissolve compounds that are important for survival, such as glucose collected when food is eaten. Water has a high specific heat capacity, so a large amount of heat is needed to increase its temperature. Thus, water absorbs a lot of heat without increasing the body's temperature. It is also present as a metabolite, which is essential for metabolism. It is also present in photosynthesis, which is needed to feed the plant.“

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There are organisms on Earth that do notneed oxygen to live. They metabolize hydrogen or methane or a number of other compounds. Plants breathe CO2 and get much of their energy from the Sun through photosynthesis. There is life at the bottom of the oceans which have never seen the sun and get all of their energy from hydrothermal vents on the seafloor.

But all life on Earth shares one thing in common: we all need water to live. Without exception.

Good thing it's so abundant.

Water is found everywhere on our planet.

It's even been found on Mars. There's probably a little bit on our Moon and Jupiter's moon Europa is basically a big ball of frozen water.

And when we aim our spectroscopes out at the universe, water is one of the most common molecules we find.

That alone might be enough to explain why we depend on it so much. You certainly wouldn't want to hinge the existence of life on a comparatively rare and scarce molecule.

But its abundance is only one reason why life depends on it so much.

Water has some pretty amazing properties that make it an ideal substrate for life.

For one, water is a liquid across a wide range of temperatures on Earth. A liquid is a much better transport medium for nutrients and other life-necessary compounds than a solid. It just happens that most of the water on Earth can exist in its liquid form.

Water is also a great solvent. It has been called the universal solvent because so many different kinds of substances can be dissolved in water. All life needs to take in substances to generate energy and flush out waste products and toxins. Because of water's knack for dissolving all kinds of substances, it makes an ideal medium for both tasks.

Water is so good at being a solvent because of its polarity.

This means the water molecule has two poles of opposite electric charge. Since each water molecule is made up of two hydrogen atoms and one oxygen, the hydrogen atoms contribute a positive charge while the oxygen contributes a negative charge, giving the molecule both positive and negative poles. This makes the water molecule not only strongly attractive to other water molecules, it will attract other polar molecules as well. This why so many substances can dissolve in water. The molecules are attracted to one another.

Water's polarity also gives it much of the properties that make it so essential for life.

Like surface tension.

Surface tension is the tendency of water molecules to adhere to one another in such way as to make its surface act as a membrane. You see surface tension at work whenever you see an insect walking on water or whenever water beads up on a surface.

This is important to life because it means water is sticky. It tends to clump together. This allows it to be sucked up as continuous stream through the roots of plants or circulated through our blood vessels against the force of gravity.

Water is the only natural substance that can be a liquid, solid, and a gas within the tight temperatures ranges of Earth. That means we get the benefits of all three phases of water.

Because water can evaporate here on Earth, it can be distributed all over the planet. Sunlight will cause water to turn into its gaseous form. Because it is less dense, the water vapor will float up into the atmosphere. But because of it's inherent stickiness, the vapor will tend to clump up around dust particles in the air and become clouds. Water basically hitches a ride on these particles as they are blown across the planet - to be deposited far and wide in the form of rain.

Ice is peculiar for a solid.

It is less dense than its liquid form and this means that it floats in liquid water.

If it didn't, life wouldn't be able to exist.

Since life got its start in water, if frozen water was denser than its liquid state that would mean that ice would sink. Ponds, lakes, and the ocean would freeze from the bottom up - killing any life within it. As it is, water freezes from the top down, allowing life to survive in the relatively warmer liquid water underneath the ice.

Anybody who has ever taken a drink of ice water on a hot day can attest to water's cooling abilities. But it does more than quench our thirst.

Water has a high specific heat.

This means it can absorb a large amount of heat without changing its temperature much. This allows the Earth's oceans to absorb excess heat and moderate the planet's temperature just as the water in our bloodstream helps us maintain a constant body temperature.

Water vapor in the atmosphere also acts as a greenhouse gas, keeping the planet warm enough to sustain life.

And the amazing properties of water may have protected the building blocks of life long enough for it travel the vast distances of interstellar space, making it possible for life to get here in the first place.

And it's because water is blue.

Small amounts of water appear clear but if you get it together in large enough quantities, water has a slight blue tinge. This is because water doesn't absorb as much blue light.

Blue light is composed of shorter more energetic wavelengths of electromagnetic radiation. This kind of radiation can sometimes be harmful to organic molecules. Space is full of this kind of radiation. Any organic molecules exposed to this radiation would quickly be destroyed. But if those same organic molecules are encased inside the frozen interior of a giant hunk of space ice (like a comet), they could feasibly be preserved from the deleterious effects of the high energy ionizing radiation of space, allowing the building blocks of life to propagate throughout the solar system - even the galaxy.

The idea that life could be spread from planet to planet via comets or other giant chunks of ice is called the Panspermia Theory. And it depends on water's radiation shielding properties to work.

Even if the building blocks of life weren't delivered via comet, the deep oceans of a Hadean era Earth may have afforded just enough shielding to keep the primordial soup from being cooked by the ultraviolet rays of a young and dangerously luminous Sun.

We don't know of any kind of lifeform that can survive without water.

That's why NASA is so focused on finding water or the right conditions for liquid water exist on other planets. It's the only indicator we have that life could be possible.

But that doesn't mean all life has to have water. Just life as we know it.

There could be alien life out there that uses alternatives to water. Ammonia and methane have similar characteristics that make them suitable substitutes.

Various solutions of ammonia have a wide range of uses on Earth - from fertilizer to window cleaner. But the ammonia molecule displays the same kind of polar flexibility that water is famous for. So it could be used as nutrient intake and waste disposal medium in the same fashion. Like water, ammonia is composed of hydrogen - the most common element in the universe. But instead of bonding with oxygen, ammonia substitutes nitrogen - also very common.

But astronomers have never identified large bodies of it.

Methane isn't a polar molecule but a lot of substances can be dissolved in it and it's pretty abundant as well.

But both ammonia and methane are only liquid at extremely low temperatures - colder than anything experienced on Earth. These conditions do exist in our solar system though.

On Saturn's moon Titan, the average temperature is a chilly -179 degrees celsius. That's cold enough to freeze a bottle of rubbing alcohol solid. Yet Titan is the only object in the solar system known to sustain liquid on its surface. This isn't water though. It's methane. Water does exist on Titan but it's frozen and as hard as stone.

If life existed on Titan, it would use methane in place of water. It would metabolize hydrogen and this should have an effect on the composition of the atmosphere - an effect large enough to be measured.

And there is some evidence of this.

There are smaller amounts of hydrogen in the lower levels of Titan's atmosphere than expected - just the kind of reading we would expect to get if something was metabolizing hydrogen on the surface.

But these results are only preliminary and they're just as likely to be evidence of how much we don't understand of the chemical processes going on in Titan's atmosphere as they are evidence of a lifeform using a biochemistry we have never encountered before.

So for now, life as we know it will have to make do with good old fashioned water.

Watch the video:

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There are organisms on Earth that do notneed oxygen to live. They metabolize hydrogen or methane or a number of other compounds. Plants breathe CO2 and get much of their energy from the Sun through photosynthesis. There is life at the bottom of the oceans which have never seen the sun and get all of their energy from hydrothermal vents on the seafloor.

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If there wasn’t enough water for all living organisms, there would be no possibility of surviving. Water is the most important need for all organisms and nothing can survive without it.

For example, humans. We should drink at least 2 liters of water per day. It increases our energy, improves skin condition, flushes out toxins or even helps to focus. Water can also help with headaches, weight loss, may help treat kidney stones or help to relieve constipation.

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1.1 The importance of water

Water is one of the most important substances on earth. All plants and animals must have water to survive. If there was no water there would be no life on earth.

Fig. 6.1: Plants and animals need water.

Apart from drinking it to survive, people have many other uses for water. These include:

cooking

washing their bodies

washing clothes

washing cooking and eating utensils; such as billies, saucepans, crockery and cutlery

keeping houses and communities clean

recreation; such as swimming pools

keeping plants alive in gardens and parks

Water is also essential for the healthy growth of farm crops and farm stock and is used in the manufacture of many products.

Fig. 6.2: Some domestic uses of water.

It is most important that the water which people drink and use for other purposes is clean water. This means that the water must be free of germs and chemicals and be clear (not cloudy).

Water that is safe for drinking is called potable water.

Disease-causing germs and chemicals can find their way into water supplies. When this happens the water becomes polluted or contaminated and when people drink it or come in contact with it in other ways they can become very sick.

Water that is not safe to drink is said to be non-potable. Throughout history there have been many occasions when hundreds of thousands of people have died because disease-causing germs have been spread through a community by a polluted water supply.

One of the reasons this happens less frequently now is that people in many countries make sure drinking water supplies are potable. Water supplies are routinely checked for germs and chemicals which can pollute water. If the water is not safe to drink it is treated. All the action taken to make sure that drinking water is potable is called water treatment.

1.2 Sources of water

There are many ways in which we can collect water. The main sources are discussed below.

Surface water

This is water which falls to the ground as rain or hail.

This water is collected from a special area called a catchment. The catchment feeds water into a holding area via rivers, streams and creeks. The water is then stored in a natural or artificial (manmade) barrier called a dam or reservoir. Dams are usually placed at the lower end of a valley.

Catchment areas are usually far away from towns or cities to lessen the chance of the water being polluted. There are laws which control human activities, such as farming and recreation in catchment areas and on dams to make sure that water supplies are kept potable.

Fig. 6.3: A surface water dam.

Rivers or lakes

Town or community water supplies are sometimes drawn directly from nearby rivers or lakes.

Fig. 6.4: Rivers and lakes can supply water.

Springs

These are found where underground water flows out of the ground naturally without the use of bores, wells or pumps.
Springs often occur towards the bottom of a hill or on sloping ground.

Fig. 6.5: A spring.

Rock catchment areas and rockholes

Sometimes large rocky outcrops contain low areas in which water is trapped. These low areas make good natural dams. Often a wall can be built to increase the amount of trapped water.

Fig. 6.6: A rockhole.

Excavated dams

Excavated dams are made by scooping out soil to make a large shallow hole. These dams are sometimes placed at the bottom of a slope to aid water collection. However, this can only be done in areas where the soil will not allow the water to drain away very easily through the ground. For example, in clay soils.

Soils which do not allow water to drain away are called impervious.

If a community wants a dam in an area where the soil is not impervious this can still be done by digging the hole and lining it with clay or an impervious liner, such as concrete or heavy plastic. Excavated dams are often used by farmers to supply water to stock.

Fig. 6.7: An excavated dam.

There is often a layer of water lying beneath the ground surface, trapped by an impervious layer of rock which will not allow it to drain away. The water may be close to ground level or it may be deep in the ground. This layer of water is called the water table.

When this water table is close to ground level the water may actually come to the surface and create a permanent wet area called a soak. This usually occurs in low lying areas or hollows.

Soaks are affected by changes in the depth of the water table. That is, if the water table drops then soaks may dry up. Some causes of this can be drought or overuse of ground water by people.

Fig. 6.8: A soak.

Rainwater tanks

The rainwater which falls on the roofs of houses is often collected using roof guttering leading through a pipe to a storage tank.

Fig. 6.9: A rainwater tank.

Note: EnHealth's monograph 'Guidance on use of Rainwater Tanks' provides the most up-to-date information and advice on the range of potential hazards that can threaten rain water tank water quality. Environmental Health Practitioners are encouraged to use the guide when planning how to prevent these hazards from contaminating rainwater, straightforward monitoring and maintenance activities and, where necessary, corrective actions. The monograph can be found on the enHealth website or by using a search engine with the title of the monograph.

Bores and wells

These are holes drilled into the ground deep enough to find a permanent (long-lasting) body of water. A pipe runs down the hole into the water and a pump is used to get the water up to ground level. The water is then pumped to the community.

Fig. 6.10: A bore.

Artesian bores

Sometimes when a bore is sunk into a low lying area the water gushes out of the hole under its own pressure. This water is under pressure because it is part of an underground body of water much of which is at a higher level than the bore opening. This kind of bore is called an artesian bore.

Fig. 6.11: An artesian bore.

A water supply taken directly from a bore or well is often called groundwater.

The water which comes from any of these sources may be salty, cloudy, smell unpleasant or have germs in it. Water of this kind would require special treatment to make it potable.

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aboriginal and torres strait islander people

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Water is one of the most important substances on earth. All plants and animals must have water to survive. If there was no water there would be no life on earth. Fig. 6.1: Plants and animals need water. Apart from drinking it to survive, people have many other uses for water.

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Water is important for all living organisms because all livings things need to grow and develop every day. It also supports body functions which are supporting our health and mind to stay alive and to be more happier tomorrow than today .

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Is there enough water for plants and animal?

The water on Earth today is all the water we have so we need to look after it. We know that humans require fresh water in order to survive but so do all other living things on our planet - kangaroos, gum trees, mushrooms, ferns and moles!

All living things are mostly made up of water. Did you know that a chicken is 75% water? An earthworm is 80% and a tomato is 95%? And you are 65% water. Which means only do we require it to live, we are in fact mostly made up of water.

Plants need water, just like all living things, to grow and stay alive. They use water directly when they capture the light energy of the sun and transform it into energy. Plants are the foundation of all food chains so animals and humans rely heavily on plants for their survival. The water cycle is also reliant on plants filtering the water and releasing it back into the atmosphere.

Animals need fresh water for their bodies to function. They gain water not only through the action of drinking but also from the food they eat. Water is vital for bodily functions such as regulation of temperature, nutrient uptake, removing wastes, body weight, and health. Losing one tenth of the body's water can results in death as the body will shut down.

Animals don't have the same luxurious that humans do when it comes to sourcing fresh water. For example, an elephant can't turn on a tap or buy a bottle of water. Some animals need to activity hunt for water in their environment in order to survive. Due to the pressure to find clean water, some species have evolved to conserve water very efficiently or vary the amount of water they intake. In hotter environmental conditions, where the demand for water is increased, the desert hopping mouse has a digestive system that conserves every drop of water like it will be their last! Similarly, camels have numerous adaptations that ensure survival without water. They can survive for up to 40 days without water, provided they consume enough green vegetation to get the moisture they need. On the other hand, amphibians, such as frogs and toads are not able to survive for more than a couple of days without a constant source of water. Frogs are especially vulnerable when it comes to water because they have semi- permeable skin, which means they can lose water very easily through their skin.

Humans need to consider other living species when thinking about water. If we are using all the water to feed our cattle, flood our crops and fill our tanks, will there be enough left for the other living things on Earth? Our reliance on extracted water from the environment has taken its toll on the health of our rivers and groundwater. Not to mention the plants and animals that live in these ecosystems.

As well as ensuring there is enough water in the environment for other species, pollution also plays an important role in the survival of animals and plants. If water is contaminated due to chemicals from humans, animals and plants may die, not because a lack of water, but due to poisoning from chemicals. It is vital that animals have a fresh source of water in order to thrive in their environment. Otherwise it is possible that certain species may die out significantly.

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Is there enough water for plants and animal? - Cool Australia

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The water on Earth today is all the water we have so we need to look after it. We know that humans require fresh water in order to survive but so do all other living things on our planet - kangaroos, gum trees, mushrooms, ferns and moles!

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It is the water from which we were created. 4.3 billion years ago, in the water began all the life.

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Importance of water on earth - Water conservation - save water - Simply E-learn kids

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Water is important for all living organisms because we are mostly water, it is our driving force. Cars cannot run without petrol and so humans can´t live without water.

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Water - Functions Of Water In The Body - Benefits Of Drinking Water

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Water is important for all living organisms because no life is possible without it. If it would disappear,  life on the planet would end.

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What would happen if water disappeared on Earth? Would we be able to survive by making water?

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Answer (1 of 98): Every living thing on earth would die, since water is a large component of all known living cells, every plant, animal, fungus, etc would all dessicate completely, and crumble to dust. With all water vapor gone from the atmosphere, the sky might change color, and become a redd...

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Water is the blood of every human being, of our planet and of every living organism, so it is important to protect or restore the finite source of water we have on our planet.

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Why Care About Water? | National Geographic

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For some organisms, water is vital to

energise and carry out functions, but for other organisms, water is a form of habitat.

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All living things need water to survive, water makes 70 percent of the human body, and blood consists of 90 percent water.

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„Water is important for all living organisms because it is important for our life and health“

If we drink much water it can cause „Hyponatremia“ and if we do not drink much water, we can have low water leves (Dehydration)- We are moody also brain works harder

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What would happen if you didn’t drink water? - Mia Nacamulli

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Water is one of the essential components that are supporting life.

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Water is very important because plants need water photosynthesis by which plants are producing CO2 which we need for breathing.

For chemical reactions in your body, for keeping your normal body temperature. Water helps to remove waste products from your body.

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I think water is important to all of us. We need water for survival and for everyday life. If we didn't have drinking water, we would die. However, the problem today is that many countries suffer from a lack of drinking water. Personally, I'm very sorry that they have a problem with water. I can't imagine being without water one day, and they must survive for several days without a drop. Water is needed all the time for drinking, hygiene, washing, traveling. There is only 2.5% of drinking water in the world and we are not doing anything about it. We're just wasting it.

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October 15 2019 / by Carlos Pavon / Water Scarcity Clock

According to our Water Scarcity Clock, water scarcity affects over 2.3 billion people in the world. Over the next decade, climate change is expected to make matters worse. Events such as the melting of tropical glaciers, desertification, and long periods of drought are expected to intensify, compromising water supply in areas with low rainfall.

How we measure water scarcity

The Water Scarcity Clock compares the population of each area with the overall water availability, creating an estimate of the amount of people suffering from water scarcity. Water stress starts when each person in any given area has on average less than 1,500m3 of water per year. When that figure goes below 1,000m3, we call it water scarcity. Areas with less than 500m3 suffer from absolute water scarcity.

Water scarcity can be caused by a physical shortage, for instance a period of drought, or it could be caused by inadequate infrastructure.

More extreme droughts are expected

Modern water infrastructure and adequate planning are vital in water scarce areas. The world is urbanizing as more and more people move into cities. Therefore, more water needs to be made available to cover the needs of city dwellers. Climate change is also expected to have a big impact. As temperatures rise, evaporation increases and soils dry out. Extreme weather events are expected to be more frequent. For example, a one-in-500-hundred-year flood can happen again just after a few years and unusually harsh droughts are becoming the new normal. To mitigate the effects of extreme weather events on water, adequate infrastructure and investment in water technologies is essential. In some areas, the only way to prevent water shortages is to manage resources as efficiently as possible.

The most threatened countries by water scarcity are in the Middle East

Israel exemplifies the fight against chronic water shortages. 93% of Israelis live in water scarce areas and they have adapted to be able to live under extreme conditions. Israeli companies have developed water efficient technologies from massive desalination plants to water efficient crops and irrigation techniques. Desalination plants provide 55% of Israel's domestic water supply and the country has the most efficient recapture system in the world, recycling 86% of used domestic water. And still, these efforts may not be enough to guarantee a long-term water supply.

In Bahrain, with no rivers, dams, or lakes in their small territory, 100% of their population are affected by absolute water scarcity. Currently, the country obtains half their water from groundwater, however, degradation of aquifers as a result of over-extraction and saltwater intrusion could compromise the future water supply. There are many other examples of water scarcity in the region: more than half of the populations of the United Arab Emirates, Lebanon, and Egypt live in water scarce areas.

Latin America: Water scarcity in Chile, Peru, and Mexico

The Atacama Desert is the world's driest desert. Situated between the Pacific Ocean and the Andes mountain range, its salt lakes and stony terrain is reminiscent of Martian landscapes. Most of the Atacama Desert is situated north of Chile, a country where more than half the population experiences water scarcity. The Atacama Desert is rich in minerals such as copper and lithium and is a top tourist destination as well. Therefore, allocation of water is a controversial topic. In the lithium-rich Salar de Atacama, mining companies need water to extract minerals and despite the extreme water scarcity in the region, there is not enough control over its use.

South of Atacama, drought is a persistent problem. Currently, the regions of Coquimbo and La Araucania are experiencing their longest drought since records began. Locals call it a mega drought. Since the 1950s, Chile has been experimenting with unconventional sources of water such as fog catchers, which collects water from the thick fog coming from the Pacific against the Andes. These devices can capture up to 10 liters of water per day and almost 3,000 of them can be installed per hectare, making the region less dependent on rainfall.

In Peru, more than half the population is located on the coast where the climate is arid and 57% live in water scarcity. Peru's water infrastructure remains underdeveloped. Around 10% of the population have no access to safe water, half of them in Lima. Peru's capital is the second biggest desert city in the word, after Cairo, and receives most of its water supply from the Andes. The Cordillera Blanca tropical glaciers, which feed rivers year-round, are decreasing at a dramatic pace due to climate change, which according to experts could compromise the water supply in some parts of Peru during the dry season.

In Mexico, 52% are affected by water scarcity. Mexico City, with its 27 million inhabitants, shows the need of adequate infrastructure to deal with floods and droughts. During the wet season, the city is hit by heavy rainfall and large areas of the city flood. However, during the dry season many inhabitants suffer cuts of the water supply; it is estimated that 40% of water is lost due to crumbling infrastructure.

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Water Scarce Countries: Present and Future | World Data Lab

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October 15 2019 / by Carlos Pavon / Water Scarcity Clock According to our Water Scarcity Clock, water scarcity affects over 2.3 billion people in the world. Over the next decade, climate change is expected to make matters worse.

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...water is important heart health: Our heart pumps 2,000 gallons of blood throughout our body aday. When we are drinking water and keeping hydrated, we are helping our heart do this job. Our heart is able to pump blood more easily when we are hydrated.

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Water is very important to the human body. Every one of your cells, organs and tissues use water to help with temperature regulation, keeping hydrated and maintaining bodily functions. In addition, water acts as a lubricant and cushions your joints. Drinking water is great for your overall health. According to the CDC everyone should drink water daily.

Water and Your Heart Health: Drinking water is very good for your heart. Your heart is working continually to pump 2,000 gallons of blood throughout your body a day. By drinking water and keeping hydrated, you are helping your heart do its job. Your heart Is able to pump blood more easily when hydrated (consuming more water than you are losing) and allows the rest of the muscles in your body to work much better.

Water and Weight Loss: Water naturally has zero calories, therefore, substituting water for soda or juice can reduce your caloric intake. Switching out one 20 oz. sugary beverage for water reduces your caloric intake by 240 calories.

There are no recommended standards for how much plain water one should drink daily because intake varies based on age, sex, weight, and many other factors. It is recommended for an adult male over the age of 19 to consume 3.7 liters of water per day. An adult non-lactating female over the age of 19 is recommended to consume 2.7 liters of water per day. Females that are pregnant or lactating are recommended to consume 3-3.8 liters of water per day. These values include the water you get from food and other (non-water) beverages throughout your day.

Hydration: Drinking water keeps you from becoming dehydrated; a condition that can cause confusion, mood change, overheating, constipation, and other symptoms. The CDC (Center for Disease Control) recommends, to decrease your risk of becoming dehydrated, that you have a drink with every meal, and drink whenever you are thirsty. An easy way to determine if you have had enough water is to check your urine. If it's a darker yellow, you need more water. If it's a pale yellow or clear you're doing great.

Don't like water? You can improve the taste of your water by adding a wedge of lemon or lime. This will help you drink more if taste has been an issue.

To learn more click on the links below!

Center for Disease Control: Water & Nutrition

Center for Disease Control: Dietary Reference Intakes

Everyday Health: The Health Benefits of Water

UPMC Heart Beat: Importance of Hydration for Your Heart

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Water is very important to the human body. Every one of your cells, organs and tissues use water to help with temperature regulation, keeping hydrated and maintaining bodily functions. In addition, water acts as a lubricant and cushions your joints. Drinking water is great for your overall health.

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Water is important for all living organisms because water is metabolite. Chemical reactions are happening in cells- these reactions are called metabolism and the chemicals are called metabolites. Since water is metabolite it is involved in for example photosynthesis, digestion and respiration.

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Why Is Water Important for Living Organisms?

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All living organisms require water for survival, although different species use it for different purposes. Water is used as a solvent, a temperature buffer, a metabolite and a living environment.

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In the video it was said that only 3% percent of water is fresh water that we can drink and only 33% from this 3% we can use. It's a very small amount of water and people spend much of water per day. We need to save more water that we actually save. For example, buy less things that we buy because gallons of water are used to make any product in shops.

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Water Facts! Learn fun facts about the thing you drink every day!

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...because how could something be unimportant when there would be nothing without it. We would not exist, animals would not exist, the life on Earth would not exist. Water is our everything.

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The Water. Looking after our Planet | Educational Video for Kids.

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People use water in agriculture to grow important plants, crops or to sustain animals with it. If there was no water, there would be no food or animals... all living organisms would die from dehydratation.

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Water use in agriculture is at the core of any discussion of water and food security. The World Bank supports countries with sustainable intensification of agriculture through critical investments in irrigation infrastructure as well as key institutional reforms.

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Because it is a source of energy, a source of necessary nutrients and the basis of all life on earth. Even the smallest creatures depend on water just like we do. Water is pure power.

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Beatriz Cordeiro, Daniela Silva, Francisco Santos and Eduardo Guerra  PT

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Beatriz Cordeiro, Daniela Silva, Francisco Santos and Eduardo Guerra  PT

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How to spare water

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Micael Ribeiro, Vítor Hugo, Manuel Martins, Tiago Clemente, Pedro Gaspar

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Micael Ribeiro, Vítor Hugo, Manuel Martins, Tiago Clemente, Pedro Gaspar

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Tomás Franco , João Rino , João Vieira e Rodrigo Rocha

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Tomás Franco , João Rino , João Vieira e Rodrigo Rocha

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Water is an essential asset for everyone and agriculture is no different since most agriculture needs water

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It helps keep skin bright.
Adequate water intake will help keep your skin hydrated and may promote collagen production. However, water intake alone isn’t enough to reduce the effects of aging.

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water can dissolve a variety of molecules and works like an universal solvent

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Water helps you digest your food. Water helps your body break down what you eat, and eases the process of digestion.

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Drinking water does more than just quench your thirst- it is essential to keeping your body functioning properly and feeling healthy.

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Water protects cells and proteins from both acids and bases. It also increases the stability of a cells structure.

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by Molly Sargen
figures by Daniel Utter

Water makes up 60-75% of human body weight. A loss of just 4% of total body water leads to dehydration, and a can be fatal. Likewise, a person could survive a month without food but wouldn't survive 3 days without water. This crucial dependence on water broadly governs all life forms. Clearly water is vital for survival, but what makes it so necessary?

The Molecular Make-up of Water

Many of water's roles in supporting life are due to its molecular structure and a few special properties. Water is a simple molecule composed of two small, positively charged hydrogen atoms and one large negatively charged oxygen atom. When the hydrogens bind to the oxygen, it creates an asymmetrical molecule with positive charge on one side and negative charge on the other side (Figure 1). This charge differential is called polarity and dictates how water interacts with other molecules.

Water is the "Universal Solvent"

As a polar molecule, water interacts best with other polar molecules, such as itself. This is because of the phenomenon wherein opposite charges attract one another: because each individual water molecule has both a negative portion and a positive portion, each side is attracted to molecules of the opposite charge. This attraction allows water to form relatively strong connections, called bonds, with other polar molecules around it, including other water molecules. In this case, the positive hydrogen of one water molecule will bond with the negative oxygen of the adjacent molecule, whose own hydrogens are attracted to the next oxygen, and so on (Figure 1). Importantly, this bonding makes water molecules stick together in a property called . The cohesion of water molecules helps plants take up water at their roots. Cohesion also contributes to water's high boiling point, which helps animals regulate body temperature .

Furthermore, since most biological molecules have some electrical asymmetry, they too are polar and water molecules can form bonds with and surround both their positive and negative regions. In the act of surrounding the polar molecules of another substance, water wriggles its way into all the nooks and crannies between molecules, effectively breaking it apart are dissolving it. This is what happens when you put sugar crystals into water: both water and sugar are polar, allowing individual water molecules to surround individual sugar molecules, breaking apart the sugar and dissolving it. Similar to polarity, some molecules are made of ions, or oppositely charged particles. Water breaks apart these ionic molecules as well by interacting with both the positively and negatively charged particles. This is what happens when you put salt in water, because salt is composed of sodium and chloride ions.

Water's extensive capability to dissolve a variety of molecules has earned it the designation of "universal solvent," and it is this ability that makes water such an invaluable life-sustaining force. On a biological level, water's role as a solvent helps cells transport and use substances like oxygen or nutrients. Water-based solutions like blood help carry molecules to the necessary locations. Thus, water's role as a solvent facilitates the transport of molecules like oxygen for respiration and has a major impact on the ability of to reach their targets in the body.

Water Supports Cellular Structure

Water also has an important structural role in biology. Visually, water fills cells to help maintain shape and structure (Figure 2). The water inside many cells (including those that make up the human body) creates pressure that opposes external forces, similar to putting air in a balloon. However, even some plants, which can maintain their cell structure without water, still require water to survive. Water allows everything inside cells to have the right shape at the molecular level. As shape is critical for biochemical processes, this is also one of water's most important roles.

Water also contributes to the formation of membranes surrounding cells. Every cell on Earth is surrounded by a membrane, most of which are formed by two layers of molecules called phospholipids (Figure 3). The phospholipids, like water, have two distinct components: a polar "head" and a nonpolar "tail." Due to this, the polar heads interact with water, while the nonpolar tails try to avoid water and interact with each other instead. Seeking these favorable interactions, phospholipids spontaneously form bilayers with the heads facing outward towards the surrounding water and the tails facing inward, excluding water. The bilayer surrounds cells and selectively allows substances like salts and nutrients to enter and exit the cell. The interactions involved in forming the membrane are strong enough that the membranes form spontaneously and aren't easily disrupted. Without water, cell membranes would lack structure, and without proper membrane structure, cells would be unable to keep important molecules inside the cell and harmful molecules outside the cell.

In addition to influencing the overall shape of cells, water also impacts some fundamental components of every cell: DNA and proteins. Proteins are produced as a long chain of building blocks called amino acids and need to fold into a specific shape to function correctly. Water drives the folding of amino acid chains as different types of amino acids seek and avoid interacting with water. provide structure, receive signals, and catalyze chemical reactions in the cell. In this way, proteins are the workhorses of cells. Ultimately proteins drive contraction of muscles, communication, digestion of nutrients, and many other vital functions. Without the proper shape, proteins would be unable to perform these functions and a cell (let alone an entire human) could not survive. Similarly, DNA needs to be in a specific shape for its instructions to be properly decoded. Proteins that read or copy DNA can only bind DNA that has a particular shape. Water molecules surround DNA in an ordered fashion to support its characteristic double-helix conformation. Without this shape, cells would be unable to follow the careful instructions encoded by DNA or to pass the instructions onto future cells, making human growth, reproduction, and, ultimately, survival infeasible .

Chemical Reactions of Water

Water is directly involved in many chemical reactions to build and break down important components of the cell. Photosynthesis, the process in plants that creates sugars for all life forms, requires water. Water also participates in building larger molecules in cells. Molecules like DNA and proteins are made of repetitive units of smaller molecules. Putting these small molecules together occurs through a reaction that produces water. Conversely, water is required for the reverse reaction that breaks down these molecules, allowing cells to obtain nutrients or repurpose pieces of big molecules.

Additionally, water buffers cells from the dangerous effects of acids and bases . Highly acidic or basic substances, like bleach or hydrochloric acid, are corrosive to even the most durable materials. This is because acids and bases release excess hydrogens or take up excess hydrogens, respectively, from the surrounding materials. Losing or gaining positively-charged hydrogens disrupts the structure of molecules. As we've learned, proteins require a specific structure to function properly, so it's important to protect them from acids and bases. Water does this by acting as both an acid and a base (Figure 4). Although the chemical bonds within a water molecule are very stable, it's possible for a water molecule to give up a hydrogen and become OH - , thus acting as a base, or accept another hydrogen and become H 3 O + , thus acting as an acid. This adaptability allows water to combat drastic changes of pH due to acidic or basic substances in the body in a process called buffering. Ultimately, this protects proteins and other molecules in the cell.

In conclusion, water is vital for all life. Its versatility and adaptability help perform important chemical reactions. Its simple molecular structure helps maintain important shapes for cells' inner components and outer membrane. No other molecule matches water when it comes to unique properties that support life. Excitingly, researchers continue to establish new properties of water such as additional effects of its asymmetrical structure. Scientists have yet to determine the physiological impacts of these properties. It's amazing how a simple molecule is universally important for organisms with diverse needs.
Molly Sargen is a first-year PhD Student in the Biological and Biomedical Sciences Program at Harvard Medical School. Dan Utter is a fifth-year PhD student in Organismic and Evolutionary Biology at Harvard University.
For More Information:
This article is part of our special edition on water. To read more, check out our special edition homepage!

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Biological Roles of Water: Why is water necessary for life? - Science in the News

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by Molly Sargen figures by Daniel Utter Water makes up 60-75% of human body weight. A loss of just 4% of total body water leads to dehydration, and a can be fatal. Likewise, a person could survive a month without food but wouldn't survive 3 days without water.

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Water boots energy. Water delivers important nutrients to all of our cells, especially muscle cells, postponing muscle fatigue.

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Water Changes Everything | charity: water

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It is the water that sustains all biological life and all human activities, from the smallest living organism to the largest living creature. Covering 70% of our world, water also constitutes an important part of our body.

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Water is the universal solvent. Water is life. Our body is made up of 75% water. Water is very important for our organs, for our body, and even for our mind to function better.

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It protects your tisues,spinal cord and joints.

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Importance of Water in Life | Importance of Water - YouTube

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Water is very important for human life Because water forms seventy-five percent of the human body. A person can endure hunger for 60 days Ken can only endure 4 more days of thirst So save water protects life

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It regulates your body temperature

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Why Do We Drink Water? | Importance Of Water | Stay Hydrated | The Dr Binocs Show | Peekaboo Kidz

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Water is life. Part of human organization comes from water.Water is always needed in order for blood circulation to exist and for the inner membranes to function without drying.

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The water is nature's balance.

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The Water. Looking after our Planet | Educational Video for Kids.

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Covering 70% of our world, water also constitutes an important part of our body.

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...in the first place it was one of the goldilocks conditions necessary for creation of life. Water is a very unique liquid with many unusual properties which may be overlooked because we take it for granted. It is fascinating that scientists are still not sure how it got on our planet.

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About 70 percent of our planet’s surface is covered with water, and it plays an important role in our daily lives. But how did water get on Earth in the first place?

Credit: Rudi Swaan Getty Images

About 70% of the surface of our planet Earth is covered in water. We are nestled in our solar system at just the right distance from the Sun for this liquid water to exist. Any farther and that water would be frozen in ice. Any closer and temperatures would be too hot and we would be at risk for a runaway greenhouse effect similar to what’s happening on the scorching surface of Venus. Our not-too-cold, not-too-hot position in the so-called ”Goldilocks zone” is a pretty good thing because, of course, water is necessary for life.

But how did that water get here? Water is a defining characteristic of our planet and it plays such an important part of our daily lives. Understanding how water arrived on Earth is a key part of understanding how and when life evolved here as well. But we don’t even know how it where it came from. Scientists are still actively researching how our planet got to be so wet in the first place.

The Early Earth

Our current picture of planet formation starts with a protoplanetary disk—that’s a large disk of gas and dust swirling around our newly-formed Sun. As the grains of dust and ice in the disk interact with themselves, those grains begin to form bigger and bigger clumps. Eventually those clumps form what we call planetesimals, the building blocks of rocky and giant planets.

But in the early period of our solar system’s formation, that disk was much hotter at the position where our Earth sits now. So even though there were most likely water molecules present in the mess of debris that made up the disk, it was too hot for water to condense into a liquid, causing it to evaporate instead. What’s more, the early Earth did not yet have an atmosphere making it easier for any liquid water droplets to be blown off into space. This leaves us with a bit of a puzzle. If the Earth could not have formed from the disk with its oceans already intact, how did they get here?

Comets vs Asteroids

If Earth’s water wasn’t formed along with the Earth, then, planetary scientists suspect, it must have been delivered later via extraterrestrial messenger. Both asteroids and comets visit the Earth and are known to harbor ice. (Not sure of the difference between an asteroid and a comet? Check out my earlier episode.) In fact, models of the compositions of asteroids and comets suggest that they even harbor enough ice to have delivered an amount of water equal to Earth's oceans.

So, problem solved? Not quite. Was it a comet or an asteroid that brought Earth’s water? Was it a single event, or many? And how long ago did this happen?

One way to determine whether an asteroid or a comet brought us our oceans is to look at the chemical make-up of these cosmic objects and compare that make-up to the Earth to see which are more alike. For example, a water molecule always has 10 protons (8 from its oxygen molecule and one each from its hydrogen molecules) and usually has 8 neutrons (from the oxygen molecule only). But different isotopes of water may have extra neutrons. Heavy water, for example, is what we call water made from oxygen and deuterium, which is an isotope of hydrogen, or just hydrogen with an added neutron.

One study published in the journal Science in 2014 looked at the relative amounts of different isotopes of water—water molecules with varying numbers of neutrons—on meteorites believed to have fallen to Earth from the ancient asteroid Vesta. Vesta is the second largest object in the Asteroid Belt and has a heavily cratered surface suggesting a violent past full of collisions.

The Vesta rock samples had the same distribution of isotopes seen on Earth. Now, that doesn’t mean that Vesta was necessarily the source of our water but that an object or objects similar to Vesta in age and in composition could be responsible.

But the dispute is still far from settled. For a while, studies of comets seemed to back up the idea that Earth’s water came from asteroids. The recent Rosetta spacecraft was the first to orbit a comet and then also the first to send a lander (called Philae) to the comet’s surface. Thanks to Rosetta and Philae, scientists discovered that the ratio of heavy water (water made from deuterium) to “regular” water (made from regular old hydrogen) on comets was different than that on Earth, suggesting that, at most, 10% of Earth’s water could have originated on a comet.

However, in 2018, a close passage of the comet 46P/Wirtanen allowed planetary scientists a more detailed look at its isotopic make-up using SOFIA, a jumbo jet with a telescope on board—very cool. They found the comet had similar ratios of deuterium and hydrogen as those found on Earth. So, what makes this comet different from the one studied by Rosetta and Philae?

Well, comet 46P/Wirtanen comes from a class of what are known as “hyperactive” comets, meaning they release more water as they draw closer to the Sun than a regular comet does. How do they do that? As a standard comet nears the heat of the Sun, the ice particles from its nucleus sublimate or go directly from solid ice to a gas, which can then condense later into liquid water if it were, say, to arrive on a planet’s surface. But a hyperactive comet loses not only the ice from its nucleus but also ice-rich particles in its atmosphere that were previously heated and released from the nucleus but still hang around. Those icy particles may be what makes hyperactive comets have isotope ratios more similar to those on Earth.

So even though hyperactive comets are rarer, the fact that they have similar isotope budgets to those seen on Earth put them back in the running for Earth’s cosmic water bearer.

»Continue reading “How Did Water Get On Earth?” on QuickAndDirtyTips.com

ABOUT THE AUTHOR(S)

Sabrina Stierwalt, PhD, is an astrophysicist at Occidental College and the host of the Everyday Einstein podcast on Quick and Dirty Tips.

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About 70 percent of our planet’s surface is covered with water, and it plays an important role in our daily lives. But how did water get on Earth in the first place?

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Water is a big part of us and we can't exist without water.

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Importance of Water in Life | Importance of Water - YouTube

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It is water that sustains all biological life and all human activities, from the smallest living organism to the largest living creature.

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Water is life.

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The water is source of live.