Acinetobacter baumanannii

Actinomyces israelii

Oli sturman

Bacteria:

• Structure: Single-celled organisms without a nucleus (prokaryotic).

• Reproduction: Can reproduce independently through cell division.

• Examples of Diseases: Cavities, urinary tract infections, strep throat.

• Treatment: Often treated with antibiotics. 

Viruses:

• Structure: Genetic material (DNA or RNA) encased in a protein coat; not considered living organisms. 

• Reproduction: Requires a host cell to replicate. 

• Examples of Diseases: Colds, flu, HIV/AIDS. 

• Treatment: Some antiviral medications can help manage viral infections, but antibiotics are ineffective. 

• Prevention: Vaccines are important for preventing some viral diseases. 

Fungi:

• Structure: Can be single-celled (yeasts) or multicellular (molds).

• Examples of Diseases: Athlete's foot, yeast infections.

• Treatment: Antifungal medications can be used. 

Protozoa:

• Structure: Single-celled organisms with a nucleus (eukaryotic).

• Examples of Diseases: Intestinal infections, amebiasis, giardiasis.

• Treatment: Antiprotozoal medications. 

Key Differences:

• Size: Viruses are the smallest, followed by bacteria, then fungi and protozoa. 

• Living vs. Non-living: Viruses are not considered living organisms because they cannot reproduce independently. 

• Treatment: Antibiotics are effective against bacteria, but not viruses. 

• Reproduction: Bacteria and protozoa can reproduce independently, while viruses need a host cell. 

The conclusions that have been drawn from these tests is that both the alpha and beta resins of hops, as well as the resin xanthohumol, have a definite ability to kill protozoa, with xanthohumol apparently being the most effective and the alpha resin the least, at least at any specific concentration.

Key aspects of fungi:

• Classification:

  Fungi are not plants or animals, but belong to their own kingdom, Fungi. 

• Structure:

  Fungi can exist as single-celled yeasts or multicellular molds and mushrooms. 

• Nutrition:

  Fungi are heterotrophic, meaning they obtain nutrients by absorbing them from their environment, rather than through photosynthesis. 

• Ecological roles:

  • Decomposers: Fungi break down dead organic matter, recycling nutrients back into the ecosystem. 

  • Symbionts: Many fungi form symbiotic relationships with plants, like mycorrhizae, where they help plants absorb nutrients and water in exchange for sugars. 

  • Pathogens: Some fungi are pathogenic, causing diseases in plants and animals. 

• Human uses:

  • Food: Mushrooms, truffles, and fermented foods like bread, beer, and soy sauce rely on fungi. 

  • Medicine: Fungi are used to produce antibiotics like penicillin, and enzymes for industrial and detergent applications. 

  • Biotechnology: Fungi are being explored for bioremediation of polluted sites, sustainable materials like leather and building materials, and even as a potential source of biofuel. 

• Diversity:

  Estimates suggest there are millions of fungal species, with only a small fraction currently identified, according to Kew Gardens and David Moore's World of Fungi. 

Bacteria

1. Oldest known life forms: Bacteria have existed on Earth for billions of years. 

2. Single-celled organisms: Bacteria are single-celled prokaryotic organisms. 

3. Diverse shapes: They come in various shapes, including spheres (cocci), rods (bacilli), and spirals (spirilla). 

4. Ubiquitous: Bacteria are found in virtually every environment on Earth. 

5. Beneficial bacteria: Some bacteria are essential for digestion, nutrient production, and immune system support. 

6. Harmful bacteria: Others can cause diseases like strep throat, pneumonia, and food poisoning. 

7. Antibiotic treatment: Many bacterial infections are treated with antibiotics. 

8. Colonies of millions: Bacteria often live in large groups or colonies. 

9. Can be used in food production: Bacteria are crucial in the production of foods like yogurt and cheese. 

10. Important for sewage treatment: Bacteria play a role in wastewater treatment. 

11. Biomining applications: Bacteria are used in mining to extract metals. 

Viruses

1. Smaller than bacteria: Viruses are even smaller than bacteria. 

2. Not true cells: Viruses lack the complex cellular structure of living organisms. 

3. Genetic material: They contain genetic material (DNA or RNA) enclosed in a protein coat. 

4. Obligate intracellular parasites: Viruses can only replicate inside living cells. 

5. Variety of shapes: Viruses have diverse shapes, some resembling crystals or rods. 

6. Can cause a wide range of illnesses: Viruses can cause colds, flu, measles, chickenpox, and HIV/AIDS. 

7. Vaccines offer protection: Vaccines are available for some viral diseases. 

8. Antiviral medications: Antiviral drugs are used to treat some viral infections. 

9. Can be challenging to treat: Many viruses are difficult to treat with medications. 

10. Mutation rates: Viruses mutate rapidly, making it hard to develop long-lasting vaccines or treatments. 

11. Spread through various routes: Viruses can be spread through respiratory droplets, bodily fluids, and other means. 

Fungi

1. Eukaryotic organisms: Fungi are eukaryotic organisms, meaning they have a nucleus. 

2. Plant-like: They are often considered plant-like but lack chlorophyll. 

3. Diverse forms: Fungi can be single-celled (yeasts) or multicellular (molds and mushrooms). 

Bacteria:

1. Bacteria are single-celled prokaryotic organisms. 

2. They are generally larger than viruses, but still microscopic. 

3. Bacteria have a cell wall, cytoplasm, and a single circular DNA molecule. 

4. They can be spherical (cocci), rod-shaped (bacilli), or spiral (vibrio, spirillum, spirochete). 

5. Bacteria reproduce through binary fission, a type of cell division. 

6. They are found in virtually every environment on Earth, including extreme conditions. 

7. Some bacteria are beneficial, while others are pathogenic (disease-causing). 

8. Beneficial bacteria aid in digestion, vitamin production, and immune system development. 

9. Pathogenic bacteria can cause infections like strep throat, food poisoning, and pneumonia. 

10. Antibiotics are effective against many bacterial infections. 

11. Bacteria can develop antibiotic resistance, making them harder to treat. 

12. Some bacteria are photosynthetic, like cyanobacteria. 

13. Others are decomposers, breaking down organic matter. 

14. Bacteria can form biofilms, which are colonies encased in a protective matrix. 

15. The study of bacteria is called bacteriology. 

16. Bacteria have been around for billions of years. 

17. They can be classified based on their response to Gram stain (Gram-positive or Gram-negative). 

18. Archaea are a type of bacteria-like organism that can live in extreme environments. 

19. Some bacteria can form spores, which are dormant and resistant to harsh conditions. 

20. Bacteria can be beneficial or harmful to humans and other organisms. 

Fungi:

1. Fungi are eukaryotic organisms, meaning they have a nucleus and other membrane-bound organelles.

2. They can be unicellular (yeasts) or multicellular (molds, mushrooms).

3. Fungi reproduce through spores.

4. They are decomposers, breaking down organic matter and releasing nutrients into the environment. 

Scientists believe they are at least as old as the first cells, which emerged around 4 billion years ago, but viruses could be even older, existing in the precellular world as self-replicating entities that subsequently evolved into How long does a virus last?

The duration of a viral infection varies widely, but most common viral illnesses like colds or the flu typically last a few days to two weeks. Some viruses, like those causing warts, can persist for much longer, even years. Chronic viral infections, such as hepatitis B and C or HIV, can last for years or even be lifelong

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Viruses: Definition, Types, Characteristics & Facts

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29 Mar 2023 — Viruses are microscopic organisms that can infect hosts, like humans, plants or animals. They're a small piece of genetic information (DNA or RNA) inside of a ...

Virus | Definition, Structure, & Facts

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A virus is an infectious agent of small size and simple composition that can multiply only in living cells of animals, plants, or bacteria.

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A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and ...

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A virus is an infectious microbe consisting of a segment of nucleic acid (either DNA or RNA) surrounded by a protein coat. A virus cannot replicate alone; ...

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Viruses are microscopic particles that are present in animals, plants, and other living organisms. They can sometimes cause diseases, such as the flu and COVID ...

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Viruses Lesson for Kids: Definition & Facts - Video

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Most viruses vary in diameter from 20 nanometres (nm; 0.0000008 inch) to 250–400 nm; the largest, however, measure about 500

Bacteria:

1. Bacteria are single-celled prokaryotic organisms. 

2. They are generally larger than viruses, but still microscopic. 

3. Bacteria have a cell wall, cytoplasm, and a single circular DNA molecule. 

4. They can be spherical (cocci), rod-shaped (bacilli), or spiral (vibrio, spirillum, spirochete). 

5. Bacteria reproduce through binary fission, a type of cell division. 

6. They are found in virtually every environment on Earth, including extreme conditions. 

7. Some bacteria are beneficial, while others are pathogenic (disease-causing). 

8. Beneficial bacteria aid in digestion, vitamin production, and immune system development. 

9. Pathogenic bacteria can cause infections like strep throat, food poisoning, and pneumonia. 

10. Antibiotics are effective against many bacterial infections. 

11. Bacteria can develop antibiotic resistance, making them harder to treat. 

12. Some bacteria are photosynthetic, like cyanobacteria. 

13. Others are decomposers, breaking down organic matter. 

14. Bacteria can form biofilms, which are colonies encased in a protective matrix. 

15. The study of bacteria is called bacteriology. 

16. Bacteria have been around for billions of years. 

17. They can be classified based on their response to Gram stain (Gram-positive or Gram-negative). 

18. Archaea are a type of bacteria-like organism that can live in extreme environments. 

19. Some bacteria can form spores, which are dormant and resistant to harsh conditions. 

20. Bacteria can be beneficial or harmful to humans and other organisms. 

Fungi:

1. Fungi are eukaryotic organisms, meaning they have a nucleus and other membrane-bound organelles.

2. They can be unicellular (yeasts) or multicellular (molds, mushrooms).

3. Fungi reproduce through spores.

4. They are decomposers, breaking down organic matter and releasing nutrients into the environment. 

Viruses are tiny particles that cause disease in people, other animals, and plants. Different viruses cause the common cold, influenza (flu), chicken pox, ...

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What is a virus? Facts for Kids - Twinkl Homework Help

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24 Jan 2023 — Viruses are types of germs that need to be in living cells to grow and reproduce. The place where viruses are found is called a host.

Are viruses alive? - BBC Bitesize

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In fact, viruses are the most diverse and numerous disease-causing organisms on Earth, infecting animals, plants, fungi and bacteria - as well as humans.

Virus Facts for Kids

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A virus is a super tiny parasite that can infect living organisms. It can make you sick! Viruses are so small you need a special electron microscope to see them ...

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What's a Virus? Science For Kids

YouTube · National Science Foundation News

24 Oct 2022

Quick facts for kids

VirusesRotavirusA diagram of an envelope virusVirus classificationGroup:

I–VII

Groups

I: dsDNA viruses
II: ssDNA viruses
III: dsRNA viruses
IV: positive-sense ssRNA virus
V: negative-sense ssRNA virus
VI: ssRNA-RT viruses
VII: dsDNA-RT viruses

A virus is a super tiny parasite that can infect living organisms. It can make you sick! Viruses are so small you need a special electron microscope to see them. They are much smaller than bacteria.

Viruses can't live or make copies of themselves alone. Instead, they sneak into another organism's cells. Once inside, they take over the cell's machinery to make many copies of themselves. After that, the cell often bursts, releasing new viruses to infect more cells. This is how all viruses reproduce.

A virus has a simple structure. It's mostly made of nucleic acid (like RNA or DNA) and a protein coat around it. Viruses don't have their own internal cell parts, like a cell wallor cell membrane. Because they live inside your cells, regular medicines like antibiotics don't work against them. Antibiotics are for bacteria, not viruses.

Viruses cause many diseases. Some examples are polio, ebola, and hepatitis. The study of viruses is called Virology.

Viruses have these key features:

• They are tiny particles that cause many diseases.

• They have a core of RNA or DNA.

• This core is protected by a protein coat.

When a virus infects an animal cell, its protein coat helps it attach to the cell's surface. For bacteria, special viruses called bacteriophages inject their genetic material right into the cell. Once the host cell has made new viruses, it often breaks open, releasing the new viruses to infect other cells. Viruses can stay active for a long time, waiting for the right conditions to infect.

Some viruses are special. Bacteriophages are viruses that infect only bacteria. Envelope viruses are tricky. When they reproduce, they wrap themselves in a piece of the host cell's outer membrane. This extra layer helps them get into new cells. Viruses like influenza and HIV use this method, making them hard to fight.

When animals get a viral infection, their immune system usually fights it off. Vaccines can also help. They teach your immune system how to fight a specific virus before you get sick. But some viruses, like those causing AIDS and hepatitis, can hide from the immune system and cause long-term infections

• They do not have an organized cell structure.

• They have no cell nucleus.

• They typically have one or two strands of DNA or RNA.

• They are covered with a protective coat of protein called the CAPSID.

• They are inactive when not inside a living cell, but are active when inside another living cell.

Why are viruses bad?

When viruses invade a body's cells and begin to multiply, they make the host sick. Viruses can cause all sorts of diseases.

How do viruses spread?

Viruses are very small and lightweight. They can float through the air, survive in water, or even on the surface of your skin. Viruses can be passed from one person to another by shaking hands, touching food, through water, or through the air when a person coughs or sneezes.

Viruses can also be passed on by insect bites, animals, or through bad food.

Examples of Viruses

There are many viruses that can infect people and make them sick. One of the most common is influenza which causes people to get the flu. Other diseases caused by viruses include the common cold, measles, mumps, yellow fever, and hepatitis.

How to Avoid Getting Infected

Bacteria do not have most of the structures found in the cells of other organisms. They are much simpler and smaller than all other cells of living things.

Bacteria take in food and send out waste through their cell walls. Most bacteria reproduce by dividing down the middle to form two separate cells. These each divide again to form a total of four cells. Through this process, billions of bacteria may form from a single bacterium in only 24 hours.

Bacteria that cause diseases can get into the human body through the nose, the mouth, and cuts in the skin. Once inside, these bacteria quickly reproduce and cause illness, called an infection. The infection may result from the bacteria themselves or from their poisonous waste products, called toxins. Luckily, the immune system of the human body can fight these threats.

Sometimes the immune system needs help in fighting off bacteria. Doctors may inject dead or weakened bacteria into the human body. This is called a vaccine. A vaccine prepares the body to fight off the same bacteria in the future. Doctors may also use medicines called antibiotics to kill bacteria in the body.

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Viruses

What are viruses?

Viruses are very small particles that can infect animals and plants and make them sick. Viruses are made up of genetic materials like DNA and are protected by a coating of protein.

Viruses hijack the cells of living organisms. They inject their genetic material right into the cell and take over. They then use the cell to make more viruses and take over more cells.

Are viruses alive?

Scientists differ on whether viruses are actually alive or not. Many people say they are non-living because they cannot reproduce without the aid of a host. Viruses also do not metabolize food into energy or have organized cells, which are usually characteristics of living things.

Characteristics of Viruses

• They do not have an organized cell structure.

• They have no cell nucleus.

• They typically have one or two strands of DNA or RNA.

• They are covered with a protective coat of protein called the CAPSID.

• They are inactive when not inside a living cell, but are active when inside another living cell.

Why are viruses bad?

When viruses invade a body's cells and begin to multiply, they make the host sick. Viruses can cause all sorts of diseases.

How do viruses spread?

Viruses are very small and lightweight. They can float through the air, survive in water, or even on the surface of your skin. Viruses can be passed from one person to another by shaking hands, touching food, through water, or through the air when a person coughs or sneezes.

Viruses can also be passed on by insect bites, animals, or through bad food.

Examples of Viruses

There are many viruses that can infect people and make them sick. One of the most common is influenza which causes people to get the flu. Other diseases caused by viruses include the common cold, measles, mumps, yellow fever, and hepatitis.

How to Avoid Getting Infected

There are things you can do to help reduce your chance of getting infected by a virus. Here are a few examples:

• Wash your hands (probably one of the most important ones).

• Don't put your hands or fingers in your mouth, nose, or eyes. Rubbing your nose or eyes can cause a virus on your hands to infect your body.

• Make sure your food is well-cooked, especially meat.

• Take your vitamins each day.

• Get plenty of sleep and exercise. This helps to strengthen your immune system to fight off viruses.

How are viruses treated?

There is little that doctors can do to treat viruses. In most cases our body's immune system fights off the virus. Scientists have developed vaccines that help our bodies to build up immunity to a specific virus. One example of a vaccine is the flu shot. The flu shot helps the body to develop its own defenses against the flu called antibodies.

Interesting Facts about Viruses

• Viruses are not classified in any of the five kingdoms of living things. This means they are not bacteria, fungi, protists, plants, or animals.

• Most viruses are so small they cannot be seen with an optical microscope.

• The word "virus" comes from the Latin word "virulentus" meaning "poisonous."

• Viruses can sometimes attack and kill bacteria.

• The first human virus discovered was the yellow fever virus in 1901 by Walter Reed.

• A virus that contains RNA instead of DNA is sometimes called a retrovirus.

• There are two main types of reproductive cycles for viruses: the lytic cycle and the lysogenic cycle.

The term "germs" refers to the microscopic bacteria, viruses, fungi, and protozoa that can cause disease.

Washing hands well and often is the best way to prevent germs from leading to infections and sickness.

Bacteria

Bacteria are tiny, single-celled organisms that get nutrients from their environments. 

Some bacteria are good for our bodies — they help keep the digestive system in working order and keep harmful bacteria from moving in. Some bacteria are used to make medicines and vaccines.

But bacteria can cause trouble too, as with cavities, urinary tract infections, ear infections, or strep throat. Antibiotics are used to treat bacterial infections.

Viruses

Viruses are even smaller than bacteria. They aren't even a full cell. They are simply genetic material (DNA or RNA) packaged inside of a protein coating. They need to use another cell's structures to reproduce, which means they can't survive unless they're living inside something else (such as a person, animal, or plant).

Viruses can only live for a very short time outside other living cells. For example, viruses in infected body fluids left on surfaces like a countertop or toilet seat can live there for a short time, but quickly die unless a live host comes along.

Once they've moved into someone's body, though, viruses spread easily and can make a person sick. Viruses are responsible for some minor sicknesses like colds, common illnesses like the flu, and very serious diseases like smallpox or HIV/AIDS.

Antibiotics are not effective against viruses. Antiviral medicines have been developed against a small, select group of viruses.

Fungi

Fungi (pronounced: FUN-guy) are multicelled, plant-like organisms. A fungus gets nutrition from plants, food, and animals in damp, warm environments.

Many fungal infections, such as athlete's foot and yeast infections, are not dangerous in a healthy person. People who have weakened immune systems (from diseases like HIV or cancer), though, may develop more serious fungal infections.

Protozoa

Protozoa (pronounced: pro-toe-ZO-uh) are one-celled organisms, like bacteria. But they are bigger than bacteria and contain a nucleus and other cell structures, making them more similar to plant and animal cells.

Protozoa love moisture, so intestinal infections and other diseases they cause, such as amebiasis and giardiasis, often spread through contaminated water. Some protozoa are parasites, which means that they need to live on or in another organism (like an animal or plant) to survive. For example, the protozoa that causes malaria grows inside red blood cells, eventually destroying them. Some protozoa are encapsulated in cysts, which help them live outside the human body and in harsh environments for long periods of time.

Medically

In such cases no virions are produced, and the infecting virus seems to disappear. Its genes, however, are passed on to each new generation of cells that stem from the original host cell. These cells remain healthy and continue to grow unless, as happens occasionally, something triggers the latent viral genes to become active. When this happens, the normal cycle of viral infection results: the viral genes direct viral replication, the host cell bursts, and the new virions are released. This pattern of infection is called lysogeny.

Closely related to lysogeny is the process known as transduction, whereby a virus carries bacterial genes from one host to another. This transduction process occurs when genes from the original host become incorporated into a virion that subsequently infects another bacterium.

Viral infections of plant and animal cells resemble those of bacterial cells in many ways. The release of new virions from plant and animal cells does not, however, always involve the bursting of the host cell as it does in bacteria. Particularly among animal viruses, the new virions may be released by budding off from the cell membrane, a process that does not necessarily kill the host cell.

In general, a viral infection produces one of four effects in a plant or animal cell: inapparent effect, in which the virus remains dormant in the host cell; cytopathic effect, in which the cell dies; hyperplastic effect, in which the cell is stimulated to divide before its death; and cell transformation, in which the cell is stimulated to divide, take on abnormal growth patterns, and become cancerous (see Cancer).

Viral infections in animals can be localized or can spread to various parts of the body. Some animal viruses produce latent infections: the virus remains dormant much of the time but becomes active periodically. This is the case with the herpes simplex viruses that cause cold sores and fever blisters.

NATURA

For a more accessible and less technical introduction to this topic, see Introduction to viruses.

VirusSARS-CoV-2, a member of the subfamily OrthocoronavirinaeVirus classification(unranked):VirusRealms

• Adnaviria

• Duplodnaviria

• Monodnaviria

• Riboviria

• Ribozyviria

• Singelaviria

• Varidnaviria

A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism.^[1] Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea.^[2][3] Viruses are found in almost every ecosystem on Earth and are the most numerous type of biological entity.^[4][5]Since Dmitri Ivanovsky's 1892 article describing a non-bacterial pathogeninfecting tobacco plants and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898,^[6]: 4 more than 16,000 of the millions of virus species have been described in detail.^[7][8] The study of viruses is known as virology, a subspeciality of microbiology.

When infected, a host cell is often forced to rapidly produce thousands of copies of the original virus. When not inside an infected cell or in the process of infecting a cell, viruses exist in the form of independent viral particles, or virions, consisting of (i) genetic material, i.e., long molecules of DNA or RNA that encode the structure of the proteins by which the virus acts; (ii) a protein coat, the capsid, which surrounds and protects the genetic material; and in some cases (iii) an outside envelope of lipids. The shapes of these virus particles range from simple helical and icosahedral forms to more complex structures. Most virus species have virions too small to be seen with an optical microscope and are one-hundredth the size of most bacteria

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protozoan, organism, usually single-celled and heterotrophic (using organic carbon as a source of energy), belonging to any of the major lineages of protists and, like most protists, typically microscopic. All protozoans are eukaryotes and therefore possess a “true,” or membrane-bound, nucleus. They also are nonfilamentous (in contrast to organisms such as molds, a group of fungi, which have filaments called hyphae) and are confined to moist or aquatic habitats, being ubiquitous in such environments worldwide, from the South Pole to the North Pole. Many are symbionts of other organisms, and some species are parasitesModern ultrastructural, biochemical, and genetic evidence has rendered the term protozoan highly problematic. For example, protozoan historically referred to a protist that has animal-like traits, such as the ability to move through water as though “swimming” like an animal. Protozoans traditionally were thought to be the progenitors of modern animals, but contemporary evidence has revealed that this is not the case for most protozoans. In fact, modern science has shown that the protozoans represent a very complicated grouping of organisms that do not necessarily share a common evolutionary history. This unrelated, or paraphyletic, nature of the protozoans has caused scientists to abandon the term protozoan in formal classification schemes. Hence, the subkingdom Protozoa is now considered obsolete. Today the term protozoan is used informally in reference to nonfilamentous heterotrophic protists.Although protozoans are no longer recognized as a formal group in current biological classification systems, protozoan can still be useful as a strictly descriptive term. The protozoans are unified by their heterotrophic mode of nutrition, meaning that these organisms acquire carbon in reduced form from their surrounding environment. However, this is not a unique feature of protozoans. Furthermore, this description is not as straightforward as it seems. For instance, many protists are mixotrophs, capable of both heterotrophy (secondary energy derivation through the consumption of other organisms) and autotrophy (primary energy derivation, such as through the capture of sunlight or metabolism of chemicals in the environment). Examples of protozoan mixotrophs include many chrysophytes. Some protozoans, such as Paramecium bursaria, have developed symbiotic relationships with eukaryotic algae, while the amoeba Paulinella chromatophora remarkably appears to have acquired autotrophy via relatively recent endosymbiosis of a cyanobacterium (a blue-green alga). Hence, many protozoans either perform

A species of honey fungus (Armillaria ostoyae) discovered in 1998 was estimated to cover roughly 2,384 acres of Oregon Forest. The fungus has survived for over 2,400 years, surviving on living and dead wood.

Mushrooms (fruiting bodies) make up only a tiny part of the fungus, with the rest living underground as networks of threads (hyphae) that make up the mycelium.
 

Help us find fungi at RHS Wisley

Help us find fungi at RHS Wisley

Fungi have a key role in cleaning the planet

Without the decomposing activities of saprotrophic fungi, we would disappear under a mountain of unrotted dead leaves and logs!

Saprotrophic fungi produce enzymes that allow them to

Decompose means to break down or decay into simpler substances. In gardening, it often refers to the process of organic matter breaking down when added to compost or soil. This process is important for creating healthy soil and providing nutrients for plants.

decomposethe tough compounds found in plant cell walls: cellulose, hemicellulose, and pectin. Some wood-decaying fungi can also decompose lignin.

These processes enable the recycling and recovery of large amounts of nutrient resources (particularly carbon and nitrogen) from dead organic matter.

What’s more, over 100 species of fungi have been found to degrade plastics, with two species being able to breakdown samples of plastics within 140 days. 
 

Fungi are more closely related to animals than to plants

Fungi are not plants or animals; they belong in their own separate kingdom. However, research has shown that fungi are closer relatives of animals than plants. In fact, the chitin that makes up fungal cell walls is also found in insect exoskeletons.
 

How many fungi are there?

There are roughly 200,000 known species of fungi across the globe, with roughly 15,000 found within the UK. Currently, scientists estimate that there could be another 2 million species of fungus yet to be discovered.
 

People have been using fungi for over 5000 years

Otzi the Iceman was discovered with two species of fungus in his pocket. The birch polypore (a white bracket fungus) found in his pocket may have acted as a natural laxative and antibiotic. Scientists think Otzi may have been self-medicating to treat gut parasites, or he was using the fungal skin as an antiseptic plaster to protect wounds.

We still use fungi in medicine today, including penicillin, an antibiotic originally manufactured from a penicillium mould.

Different species of fungi are being investigated to see if their presence can improve our gardens. Scientists at the RHS are currently exploring whether saprotrophic fungi presence in the soil can protect plants from honey fungus infection.

For a more accessible and less technical introduction to this topic, see Introduction to viruses.

VirusSARS-CoV-2, a member of the subfamily OrthocoronavirinaeVirus classification(unranked):VirusRealms

• Adnaviria

• Duplodnaviria

• Monodnaviria

• Riboviria

• Ribozyviria

• Singelaviria

• Varidnaviria

A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism.^[1] Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea.^[2][3] Viruses are found in almost every ecosystem on Earth and are the most numerous type of biological entity.^[4][5]Since Dmitri Ivanovsky's 1892 article describing a non-bacterial pathogeninfecting tobacco plants and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898,^[6]: 4 more than 16,000 of the millions of virus species have been described in detail.^[7][8] The study of viruses is known as virology, a subspeciality of microbiology.

When infected, a host cell is often forced to rapidly produce thousands of copies of the original virus. When not inside an infected cell or in the process of infecting a cell, viruses exist in the form of independent viral particles, or virions, consisting of (i) genetic material, i.e., long molecules of DNA or RNA that encode the structure of the proteins by which the virus acts; (ii) a protein coat, the capsid, which surrounds and protects the genetic material; and in some cases (iii) an outside envelope of lipids. The shapes of these virus particles range from simple helical and icosahedral forms to more complex structures. Most virus species have virions too small to be seen with an optical microscope and are one-hundredth the size of most bacteria

Viruses are fascinating and sometimes perplexing entities. They are not truly alive in the same way that cells are, as they lack the ability to reproduce independently and don't possess their own metabolism. Instead, they rely on host cells to replicate. Here are some fun facts about viruses: 

• Size Matters:

  Viruses are incredibly small, with some being 400 nanometers (like mimiviruses) and others as small as 20 nanometers (like circoviruses). 

• Not Always Harmful:

  While some viruses cause infections, many harmless viruses live inside us. 

• Ancient Entities:

  Scientists believe viruses may be as old as the first cells, or even older, potentially existing before cells evolved. 

• Shape Shifters:

  Viruses come in diverse shapes, some resembling spiky balls, others like spiders in space helmets. 

• No Metabolism:

  Viruses don't have a metabolism; they can't produce their own food or energy. 

• Replication Strategy:

  Viruses hijack host cells to replicate, turning them into virus factories. 

• Not Just Animals and Plants:

  Viruses can infect both animals and plants, with the tobacco mosaic virus being the first one discovered. 

• Can Cause Cancer:

  While most viral infections don't lead to cancer, certain viruses are linked to cancers like cervical cancer and liver cancer. 

• Can Mutate:

  Viruses can change and evolve, which can lead to new strains that may be resistant to existing vaccines. 

• Not All are Bad:

  Biologists estimate that trillions of harmless viruses live inside us. 

• The Virocell Model:

  The "virocell" model suggests that the infected cell itself can be considered the living form of the virus. 

• Can be Frozen:

  Viruses can be frozen without being damaged, and they become active again when warmed up. 

• Oldest Known Virus:

  The yellow fever virus was the first human virus discovered by Walter Reed in 1901. 

What is long COVID?

Most people with COVID-19 feel better within a few days or weeks of their first symptoms and make a full recovery within 12 weeks.

For some people, symptoms can last longer. This is called long COVID or post COVID-19 syndrome. Long COVID is a new condition which is still being studied.

Read about long COVID research studies on the National Institute for Health and Care Research (NIHR) website.

Information:

You can sign up to take part in long COVID research on the Be Part of Research website

Symptoms of long COVID

The most common symptoms of long COVID are:

• extreme tiredness (fatigue)

• feeling short of breath

• problems with your memory and concentration ("brain fog")

• heart palpitations

• dizziness

• joint pain and muscle aches

However, there are lots of symptoms you can have after a COVID-19 infection, including:

• loss of smell

• chest pain or tightness

• difficulty sleeping (insomnia)

• pins and needles

• depression and anxiety

• tinnitus, earaches

• feeling sick, diarrhoea, stomach aches, loss of appetite

• cough, headaches, sore throat, changes to sense of smell or taste

• rashes

Non-urgent advice:

Tiny but Mighty:

• Size Range:

  While most protozoa are microscopic, some can be large enough to be seen with the naked eye, like the freshwater spirostomum, which can be up to 3 mm long. 

• Diverse Shapes:

  Protozoa exhibit a wide range of shapes, from spherical and oval to elongated and constantly changing, as seen in amoebas. 

• Cellular Complexity:

  They are eukaryotic, meaning they have a nucleus and other complex internal structures like animal cells. 

• Locomotion:

  Many protozoa can move using cilia (hair-like structures) or flagella (whip-like structures). Some, like amoebas, move by extending parts of their cell (pseudopods) and flowing into them. 

Ecological Roles:

• Nutrient Cycling:

  Protozoa are important players in nutrient cycling, especially in aquatic environments, by consuming bacteria and algae and making nutrients available for other organisms. 

• Food Web Dynamics:

  They form a crucial part of the microbial food web, serving as prey for larger organisms and also influencing the populations of bacteria and algae. 

• Diverse Habitats:

  Protozoa can be found in various habitats, including freshwater, marine environments, soil, and even inside other organisms (as parasites). 

Unique Characteristics:

• Reproduction:

  Most protozoa reproduce asexually, meaning they don't need a partner to multiply. 

• Cyst Formation:

  When conditions become unfavorable (like lack of food or water), some protozoa can form cysts, which are protective structures that allow them to survive until conditions improve. 

• Parasitic Protozoa:

  Some protozoa are parasitic, meaning they live inside other organisms (hosts) and can cause diseases in humans and animals, such as malaria caused by Plasmodium. 

• Evolutionary History:

  Protozoa were likely one of the earliest forms of life on Earth, playing a significant role in the evolution of life. 

• Complex Life Cycles:

  Some protozoa have complex life cycles that may involve multiple host species. 

It’s like someone breaking into your house to use your kitchen. The virus brought its own recipe, but it needs to use your dishes, measuring cups, mixer and oven to make it. (Unfortunately, they usually leave a big mess when you finally kick them out.)

Viruses are also sometimes called “virions.”

Virus features

Viruses share some common features. Viruses:

• Are made up of genetic material (RNA or DNA) and a protective protein coating (capsid).

• Sometimes have another layer called an envelope around the capsid. Viruses without an envelope are called “naked viruses.”

• Are similar to parasites — they need a host to reproduce. They’ll survive outside of a host until their capsid breaks down over time.

• Are 100 to 1,000 times smaller than the cells in your body.

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What are the types of viruses?

Experts group viruses into categories — like family and genus — based on similar features, like size, shape and the type of genetic material they carry. Some common types of viruses that you might hear about include:

• Influenza viruses.

• Human herpesviruses.

• Coronavirus.

• Human papillomaviruses.

• Enteroviruses.

• Flaviviruses.

• Orthopoxviruses.

• Hepatitis viruses.

There are also some viruses that have unique qualities, like retroviruses and oncoviruses.

Influenza viruses (Orthomyxoviridae)

The Orthomyxoviridae family of viruses includes influenza A and B, which cause the flu. Strains of influenza A also cause avian flu (“bird flu”) and swine flu (H1N1).

Human herpesvirus (Herpesviridae)

Herpesviridae is a large family of viruses. They cause several types of illnesses, like oral and genital herpes, chickenpox, shingles, Epstein-Barr and cytomegalovirus (CMV).

Coronaviruses

Coronaviruses are a subfamily of viruses. SARS-CoV-2, the virus that causes COVID-19, is probably the most well-known coronavirus. But other types of coronaviruses cause mild illnesses, like a cold.

Human papillomavirus (HPV)

Human papillomaviruses are part of the Papillomaviridae family of viruses. They cause warts. Some types of HPV can lead to cancers.

Enteroviruses

Enterovirus is a genus (one level smaller than the group called a “family”) of viruses that infect your intestinal tract. Types of enteroviruses cause polio and hand, foot and mouth disease.

Flaviviruses

Viruses in this genus are often spread by mosquitoes. They cause illnesses like Zika, West Nile, dengue fever and yellow fever.

Orthopoxviruses

Viruses in the genus Orthopoxvirus cause blistering rashes. Mpoxand smallpox are orthopoxviruses.

Hepatitis viruses

Though they don’t all belong to the same family or genus, hepatitis viruses all infect your liver. Hepatitis A, B and C are the most common.

Retroviruses

Retroviruses are RNA viruses that use special proteins to make DNA. The virus then inserts its DNA into yours. Your cells read the viral DNA as if it were its own instructions. HIV and human T-lymphotropic virus 1 (HTLV-1) are retroviruses.

Oncoviruses

Oncoviruses are viruses that can cause cancer. Viruses that have been linked to specific cancers include:

Facts

Fungi are unique and have their own kingdom, distinct from plants and animals.

Fungi play a vital role in breaking down dead plants and animals, returning nutrients to the environment.

Fungi are made of tiny threads called hyphae, which form network called mycelium.

Fungi Reproduce using spores, which are like tiny seeds.

Yeast is used to make bread rice and is also used in brewing beer.

Some mushrooms are edible and delicious, while others are poisonous.

Some fungi cause diseases,Like athlete’s foot, while others produce medicines like penicillin.

Some fungi, like Cordyceps, can control the minds of insects like ants.

One massive fungus in Oregon covers a huge area and is considered the largest living organism

Here's a breakdown for a child:

• Tiny and single-celled: Protozoa are very, very small, and each one is just one tiny cell. 

• Animal-like: They move around and eat other things, like little animals. 

• Found in water: They like to live in places with water, like ponds or puddles. 

• Some are like tiny bullies: Some protozoa can make other animals or plants sick. 

• Examples: A well-known example is the paramecium, which has tiny hairs called cilia that help it move around. 

Some are helpful some are harmful:

Well, some fungus are helpful like those and making food others can cause problems like athletes foot.

.mushrooms: the part we see above ground is just the fruiting body, the rest is a network of threads called mycelium underground.

Moulds: you might see growing on old food

Yeast : these are used to make bread and other food rise