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C - How well do you know living VS non-living things?

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C - How well do you know living VS non-living things?

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Take a try at this quick quiz that covers living vs non-living things. Good luck!!!!

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Quiz Yourself! Living vs Non-living Things

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Before you begin this assignment, make sure you have reviewed the Slide Presentation and have taken notes.

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Characteristic #7 - All living things have the ability to GROW AND DEVELOP! 

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Characteristic #7 - All living things have the ability to GROW AND DEVELOP! 

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Growth is the increases and size of the organism. Development involves the transformation of the organism as it goes through the growth process.

Recall how a baby grows and develops into a full grown adult.

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Characteristic #6 - All living things USE ENERGY!

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Characteristic #6 - All living things USE ENERGY!

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Organisms use energy to carry out the activities of life.

These activities include making food, breaking food down, moving materials into and out of cells, and building cells.

We will cover this when we discuss cellular processes.

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Characteristic #5 - All living things CONTAIN DNA!

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Characteristic #5 - All living things CONTAIN DNA!

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DNA is the abbreviation for deoxyribonucleic acid! In science, you will use this word a lot!

When organisms reproduce, they pass copies of their DNA to their offspring. This makes every individual unique.

There is a video on the link below that shows how DNA is used to make up organisms.

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The order of building blocks in a strand of DNA makes up a "sequence." We can read a DNA sequence like letters in a book. In fact, we know the sequence of the entire human genome-all 3 billion letters. That's enough information to fill roughly 1,000 200-page books!

Contained within the 3 billion letters of the human genome are about 21,000 genes. Most of our known genes code for proteins, but some code for RNA molecules.

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The order of building blocks in a strand of DNA makes up a "sequence." We can read a DNA sequence like letters in a book. In fact, we know the sequence of the entire human genome-all 3 billion letters. That's enough information to fill roughly 1,000 200-page books!

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Characteristic #4 - All living things have the ability to REPRODUCE!

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Characteristic #4 - All living things have the ability to REPRODUCE!

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To reproduce means to make more! Reproducing is what keeps the world living! Animals reproduce, humans reproduce, even plants reproduce! There are two different types of reproduction that we will cover during our genetics unit: asexual and sexual reproduction. In the picture you will also see bacteria reproducing.

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Characteristic #3 - All living things maintain HOMEOSTASIS

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Characteristic #3 - All living things maintain HOMEOSTASIS

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A simple definition for homeostasis is maintaining a stable environment. All living things maintain homeostasis.

For example, your body maintains a constant temperature. When you get hot, you sweat. When you get cold, you shiver. Explore the link to learn more about homeostasis.

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(Image credit: Shutterstock)

Homeostasis is the ability to maintain a relatively stable internal state that persists despite changes in the world outside. All living organisms, from plants to puppies to people, must regulate their internal environment to process energy and ultimately survive. If your blood pressure skyrockets or body temperature plummets, for example, your organ systems may struggle to do their jobs and eventually fail.

Why homeostasis is important

Physiologist Walter Cannon coined the term "homeostasis" in the 1920s, expanding on previous work by late physiologist Claude Bernard. In the 1870s, Bernard described how complex organisms must maintain balance in their internal environment, or "milieu intérieur,"in order to lead a "free and independent life"in the world beyond. Cannon honed the concept, and introduced homeostasis to popular audiences through his book, "The Wisdom of the Body"(The British Medical Journal, 1932). [ The 7 Biggest Mysteries of the Human Body]

Hailed as a core tenet of physiology, Cannon's basic definition of homeostasis remains in use today. The term derives from Greek roots meaning "similar" and "a state of stability." The prefix "homeo" stresses that homeostasis doesn't work like a thermostat or cruise control in a car, fixed at one precise temperature or speed. Instead, homeostasis holds important physiological factors within an acceptable rangeof values, according to a review in the journal Appetite.

The human body, for example, regulates its internal concentrations of hydrogen, calcium, potassium and sodium, charged particles that cells rely on for normal function. Homeostatic processes also maintain water, oxygen, pH and blood sugar levels, as well as core body temperature, according to a 2015 review in Advances in Physiology Education.

In healthy organisms, homeostatic processes unfold constantly and automatically, according to Scientific American. Multiple systems often work in tandem to hold steady a single physiological factor, like body temperature. If these measures falter or fail, an organism may succumb to disease, or even death.

How homeostasis is maintained

Many homeostatic systems listen for distress signals from the body to know when key variables fall out of their appropriate range. The nervous system detects these deviations and reports back to a control center, often based in the brain. The control center then directs muscles, organs and glands to correct for the disturbance. The continual loop of disturbance and adjustment is known as "negative feedback," according to the online textbook Anatomy and Physiology.

For example, the human body maintains a core temperature of about 98.6 degrees Fahrenheit (37 degrees Celsius). When overheated, thermosensors in the skin and brain sound an alarm, initiating a chain reaction that directs the body to sweat and flush. When chilled, the body responds by shivering, and reducing blood circulation to the skin. Similarly, when sodium levels spike, the body signals the kidneys to conserve water and expel excess salt in concentrated urine, according to two NIH-funded studies.

Animals will also adjust their behavior in response to negative feedback. For example, when overheated, we may shed a layer of clothing, move into the shade, or drink a cold glass of water.

Modern models of homeostasis

The concept of negative feedback dates back to Cannon's description of homeostasis in the 1920s, and was the first explanation of how homeostasis works. But in recent decades, many scientists argue that organisms are able to anticipate potential disruptions to homeostasis, rather than only reacting to them after the fact.

This alternate model of homeostasis, known as allostasis, implies that the ideal set point for a particular variable can shift in response to transient environmental changes, according to a 2015 article in Psychological Review. The point may shift under the influence of circadian rhythms, menstrual cycles or daily fluctuations in body temperature. Set points may also change in response to physiological phenomena, like fever, or to compensate for multiple homeostatic processes taking place at the same time, according to a 2015 review in Advances in Physiology Education.

"The set points themselves aren't fixed but can show adaptive plasticity," said Art Woods, a biologist at the University of Montana in Missoula. "This model allows for anticipatory responses to upcoming potential disturbances to set points."

For example, in anticipation of a meal, the body secretes extra insulin, ghrelin and other hormones, according to a 2007 review in Appetite. This preemptive measure readies the body for the incoming flood of calories, rather than wrestling to control blood sugar and energy stores in its wake.

The ability to shift set points allows animals to adapt to short-term stressors, but they may fail in the face of long-term challenges, such as climate change.

"Activating homeostatic response systems can be fine for short periods of time," Woods said. But they're not designed to last for long. "Homeostatic systems can fail catastrophically if they are pushed too far; so, although systems may be able to handle near-term novel climates, they may not be able to handle larger changes over longer periods of time."

(Image credit: Shutterstock)

Keeping information flowing

Homeostatic systems may have primarily evolved to help organisms maintain optimal function in different environments and situations. But, according to a 2013 essay in the journal Trends in Ecology & Evolution, some scientists theorize that homeostasis primarily provides a "quiet background" for cells, tissues and organs to communicate with each oth er. The th eory posits that homeostasis makes it easier for organisms to extract important information from the environment and shuttle signals between body parts.

Regardless of its evolutionary purpose, homeostasis has shaped research in the life sciences for nearly a century. Though mostly discussed in the context of animal physiology, homeostatic processes also enable plants to manage energy stores, nourish cells and respond to environmental challenges. Beyond biology, the social sciences, cybernetics, computer science and engineering all use homeostasis as a framework to understand how people and machines maintain stability despite disruptions.

Check out helpful graphics about homeostasis from the Khan Academy.

Learn how homeostasis impacts human physiology with Crash Course.

Watch this video from the Amoeba Sisters to learn more about negative feedback.

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(Image credit: Shutterstock) Homeostasis is the ability to maintain a relatively stable internal state that persists despite changes in the world outside. All living organisms, from plants to puppies to people, must regulate their internal environment to process energy and ultimately survive.

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Characteristic #2 - All living things RESPOND TO STIMULI

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Characteristic #2 - All living things RESPOND TO STIMULI

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All living organisms can sense change in their environment and respond to that change.

A stimulus is a change that affects the activity of the organism.

Example: Watch the video below to see the how the touch of an insect triggers the Venus' flytrap to close its leaves quickly as an example of responding to stimuli.

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VENUS FLYTRAP JAWS OF DOOM!!     2016 compilation

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Characteristic #1 - All living things are made of CELLS

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Characteristic #1 - All living things are made of CELLS

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All living things are composed up of one or more cells. (unicellular vs multicellular)

Cells are the smallest, basic building  blocks to all living things.

If you click on the link below, you will be able to compare the size of a cell to different things such as a coffee bean all the way to a carbon atom.

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Some cells are visible to the unaided eye

The smallest objects that the unaided human eye can see are about 0.1 mm long. That means that under the right conditions, you might be able to see an amoeba proteus, a human egg, and a paramecium without using magnification. A magnifying glass can help you to see them more clearly, but they will still look tiny.

Smaller cells are easily visible under a light microscope. It's even possible to make out structures within the cell, such as the nucleus, mitochondria and chloroplasts. Light microscopes use a system of lenses to magnify an image. The power of a light microscope is limited by the wavelength of visible light, which is about 500 nm. The most powerful light microscopes can resolve bacteria but not viruses.

To see anything smaller than 500 nm, you will need an electron microscope. Electron microscopes shoot a high-voltage beam of electrons onto or through an object, which deflects and absorbs some of the electrons. Resolution is still limited by the wavelength of the electron beam, but this wavelength is much smaller than that of visible light. The most powerful electron microscopes can resolve molecules and even individual atoms.

Adenine

The label on the nucleotide is not quite accurate. Adenine refers to a portion of the molecule, the nitrogenous base. It would be more accurate to label the nucleotide deoxyadenosine monophosphate, as it includes the sugar deoxyribose and a phosphate group in addition to the nitrogenous base. However, the more familiar "adenine" label makes it easier for people to recognize it as one of the building blocks of DNA.

How can an X chromosome be nearly as big as the head of the sperm cell?

No, this isn't a mistake. First, there's less DNA in a sperm cell than there is in a non-reproductive cell such as a skin cell. Second, the DNA in a sperm cell is super-condensed and compacted into a highly dense form. Third, the head of a sperm cell is almost all nucleus. Most of the cytoplasm has been squeezed out in order to make the sperm an efficient torpedo-like swimming machine.

The X chromosome is shown here in a condensed state, as it would appear in a cell that's going through mitosis. It has also been duplicated, so there are actually two identical copies stuck together at their middles. A human sperm cell contains just one copy each of 23 chromosomes.

A chromosome is made up of genetic material (one long piece of DNA) wrapped around structural support proteins (histones). Histones organize the DNA and keep it from getting tangled, much like thread wrapped around a spool. But they also add a lot of bulk. In a sperm cell, a specialized set of tiny support proteins (protamines) pack the DNA down to about one-sixth the volume of a mitotic chromosome.

Carbon

The size of the carbon atom is based on its van der Waals radius.

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The smallest objects that the unaided human eye can see are about 0.1 mm long. That means that under the right conditions, you might be able to see an amoeba proteus, a human egg, and a paramecium without using magnification. A magnifying glass can help you to see them more clearly, but they will still look tiny.

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B - Video Overview of The Characteristics of Living Things

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B - Video Overview of The Characteristics of Living Things

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How do we group or classify things as living or non-living? What characteristics makes an organism "living"? Watch this short video to explore the 7 characteristics that classifies an organism living.

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A - Introduction to Characteristics of Living Things

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A - Introduction to Characteristics of Living Things

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This google slide presentation gives an introduction to Unit 1 - Organization of Living Things. In this presentation, you will find the 7 specific characteristics that categorizes something as living.