Fungi



Fungi 2800
Photo by: Rafal Olechowski

Fungi (plural of fungus) are one of the five kingdoms of organisms. Kingdoms are the main divisions into which scientists classify all living things on Earth. The other kingdoms are: Monera (single-celled organisms without nuclei), Protista (single-celled organisms with a nucleus), Plantae (plants), and Animalia (animals).

Fungi constitute a large and diverse group of organisms. The kingdom of fungi is divided into four major groups: conjugating fungi, sac fungi, club fungi, and imperfect fungi. Mushrooms, molds, yeasts, and mildew are all fungi. Biologists have estimated that there are more than 200,000 species of fungi in nature, although only about 100,000 have been identified so far. The scientific study of fungi is called mycology.

General characteristics

The different groups of fungi have different levels of cellular organization. Some groups consist of single-celled organisms that have a single nucleus per cell. (A nucleus is a membrane-enclosed structure within a cell that contains the cell's genetic material and controls its growth and reproduction.) Other groups consist of single-celled organisms in which each cell has hundreds or thousands of nuclei. Still others consist of multicellular organisms that have one or two nuclei per cell. The bodies of multicellular fungi usually consist of slender, cottony filaments called hyphae. A mass of hyphae is called a mycelium. The mycelium carries on all the life-maintaining processes of the organism, including sexual reproduction (in most species).

Unlike plants, fungi do not contain chlorophyll (green pigment) and thus cannot create their own food through photosynthesis (the chemical process by which plants containing chlorophyll use sunlight to convert carbon dioxide and water to carbohydrates, releasing oxygen as a byproduct).

Most species of fungi grow on land and obtain their nutrients from dead organic matter. Most species feed by secreting enzymes, which partially break down the food. The fungi then absorb the partially digested food to complete digestion internally. Because fungi (along with bacteria) help decompose dead plants, animals, and other organic matter, they serve an important ecological role. They release large amounts of carbon dioxide into the atmosphere and recycle nitrogen and other important nutrients for use by plants and other organisms.

Some fungi are parasites, living in or on another organism (called a host) from which they obtain their nutrients. This relationship usually harms the host. Such parasitic fungi usually have specialized tissues called haustoria that penetrate the host's body. Most of the diseases that afflict agricultural plants are caused by parasitic fungi. Some examples are corn smut, black stem rust of wheat and barley, and cotton root rot. Some species of fungi also can parasitize animals. Fungi that parasitize humans cause diseases such as athlete's foot, ringworm, and yeast infections.

Words to Know

Carbohydrate: A compound consisting of carbon, hydrogen, and oxygen found in plants and used as a food by humans and other animals.

Hyphae: Slender, cottony filaments making up the body of multicellular fungi.

Nucleus: Membrane-enclosed structure within a cell that contains the cell's genetic material and controls its growth and reproduction.

Parasite: Organism living in or on another organism (called a host) from which it obtains nutrients.

Photosynthesis: Chemical process by which plants containing chlorophyll use sunlight to convert carbon dioxide and water to carbohydrates, releasing oxygen as a by-product.

Symbiosis: Close relationship between two organisms of different species, which often benefits each member.

Conjugating fungi

There are about 600 species of conjugating fungi. Most species are land-based and feed on organic matter, although there are a few parasitic species. The algaelike conjugating fungi have a continuous mycelium containing hundreds or thousands of nuclei, with no divisions between them. Species of conjugating fungi cause potato blight, downy mildew, black bread mold, and water mold (which affects dead leaves and sticks in water).

Sac fungi

Sac fungi are so-named because many species in this group reproduce sexually by forming a spore-filled structure called an ascus, which means literally "a sac." This large group of fungi includes many species

An American fly agaric. This mushroom is very common in all of North America, but it is somewhat more rare in the southern states, where specimens are more slender and tinged with a salmonlike color. (Reproduced by permission of Field Mark Publications.)
An American fly agaric. This mushroom is very common in all of North America, but it is somewhat more rare in the southern states, where specimens are more slender and tinged with a salmonlike color. (Reproduced by permission of
Field Mark Publications
.)

that are beneficial to humans. For example, yeasts are a major group of sac fungi. Different yeasts are used by bakers, brewers, and vintners to make their bread, beer, or wine. Truffles, regarded as a food delicacy, are underground sac fungi that grow in association with tree roots.

Some species of sac fungi appear as blue-green molds on fruits, vegetables, and cheeses. Several other species are important for the making of cheeses, such as blue cheese.

Some other sac fungi cause plant diseases. These include chestnut blight (a disease that virtually wiped out the American chestnut as a mature forest tree) and Dutch elm disease.

Lichens

A lichen is the product of a symbiotic (mutually beneficial) relationship between fungi and blue-green or green algae. The resulting structure resembles neither species. Typically, the algae supply carbohydrates to the fungi and the fungi supply nitrogen and other nutrients to the algae. Lichens can be very colorful, ranging from bright reds and oranges to yellows and greens, with white, gray, and black hues.

Many lichens can inhabit harsh environments and withstand prolonged periods of drought. In the temperate region of North America, lichens often grow on tree trunks and bare rocks and soil. In Antarctica, they have been found growing upon and within rocks. In the Arctic, the lichen species commonly known as reindeer mosses are important in the diets of caribou and reindeer.

Club fungi

Club fungi species reproduce sexually by forming spores on top of club-shaped structures called basidia. The club fungi are believed to be closely related to the sac fungi. This large group includes species that are known as mushrooms, toadstools, earthstars, stinkhorns, puffballs, jelly fungi, coral fungi, and many other interesting names. Some species, such as the rusts and smuts, cause disease in agricultural grains. Other species, such as the fly agaric, produce chemical hallucinogens (chemicals that induce visions) and have been used by numerous cultures in their religious ceremonies.

A significant species of club fungi is called mycorrhizae, which means "fungus root." Mycorrhizal fungus form a symbiotic relationship with many types of plant roots. (Symbiosis is the close association between two organisms of different species, which often benefits each member.) The fungus typically supplies nitrogen-containing compounds to the plant, and the plant supplies carbohydrates and other organic compounds to the fungus. Mycorrhizal fungus are very important for the growth of orchids and many trees, including pines and beeches.

Imperfect fungi

Mycologists have never observed the sexual reproduction of fungi in the imperfect fungi group. Since this part of their life cycle is missing, they are referred to as imperfect fungi. These fungi may have lost their sexual phase through the course of evolution. Species in this group produce plant and animal diseases. Athlete's foot and ringworm in humans are caused by imperfect fungi.

Some species in this group appear as blue-green molds on fruits, vegetables, and cheeses. Several other species are important for the making of cheeses such as blue cheese, Roquefort, and Camembert. Certainly the best known product obtained from this group of fungi is penicillin, the first widely used antibiotic. Penicillin was first discovered in the mold Penicillium notatum by Scottish bacteriologist Alexander Fleming (1881–1955) in 1928. Scientists now know it is produced by other species in this group, as well.

[ See also Fermentation ; Hallucinogens ; Parasite ; Yeast ]



User Contributions:

1
kimmy
Report this comment as inappropriate
Oct 10, 2006 @ 7:19 pm
this really helped me with my assignment. this has everything from pictures to facts, just perfect, they should have this for all the kingdoms. well thanks for the help and plz do continue doing this wonderful job
2
Ridley
Report this comment as inappropriate
Mar 1, 2007 @ 3:15 pm
This is great, but the only thing I think you are missing are Common molds. From what I have learned this year, Common molds are considered fungi, and I think would help a lot. I think a couple more pictures would be cooler too. Overall, AMAZING!
3
miranda
Report this comment as inappropriate
Dec 13, 2007 @ 1:13 pm
This website helps me and my class so much!!! thANKS
4
Cassandra
Report this comment as inappropriate
Feb 27, 2008 @ 5:17 pm
This helped me a lot for a study sheet! Thanks much!
5
erika
Report this comment as inappropriate
Mar 1, 2008 @ 1:13 pm
thank you !This help with my science project and i got a 92 on it.
6
sangeeta
Report this comment as inappropriate
May 1, 2008 @ 11:23 pm
nice article with lot of information . nice pictures
7
Adrianne
Report this comment as inappropriate
Oct 28, 2008 @ 5:17 pm
hey thanks for the help!!! and i got a 100 on all mi assignments that i had to do about fungi!!!!!
8
vikas sharma
Report this comment as inappropriate
Aug 22, 2009 @ 9:09 am
you describe all about the fungi but there species and characteristic are also added and you don't describe about molds. in end, its great article and help many people. good work & best of luck for future.
9
mike
Report this comment as inappropriate
Nov 30, 2009 @ 9:09 am
OK FOR ME I LIKE YOU TO SEND ME INFORMATION ABOUT NEW DEVELOPMENT
10
cecille april
Report this comment as inappropriate
Jan 1, 2010 @ 4:04 am
thanks for the information. this really helped me.:)
11
Report this comment as inappropriate
Feb 15, 2010 @ 4:04 am
this will help me for my studying in fungi.:)
thank you
12
bunjaub
Report this comment as inappropriate
Aug 18, 2010 @ 8:20 pm
haey. thanks for the help and i got a 100 on all my assignments
13
Report this comment as inappropriate
Oct 12, 2010 @ 8:08 am
Hey thanks a lot for the study sheet lol it helped alot (:
14
Report this comment as inappropriate
Nov 14, 2010 @ 5:05 am
GOOD INFORMATION,AMMAZING AND WELL DONE GOOD JOB KEEP IT UP
15
Report this comment as inappropriate
Dec 6, 2010 @ 8:08 am
I need to know more about fungi that is associated with crayfish
16
Report this comment as inappropriate
Feb 2, 2011 @ 5:05 am
` haha . really need this one. Thanks for the info's . It's really usefull .!
17
Report this comment as inappropriate
Feb 26, 2011 @ 3:15 pm
Marvellous, absolutely marvellous. This is 100% excellent. can't wait to murder Bot 201 exam this semester. Thanks alot men.
18
Report this comment as inappropriate
Mar 7, 2011 @ 6:06 am
I would like to know the effect of molds on agricultural productivity and the various species of molds that are found both in the field and in storage.
19
ISA HALLIRU ISIAKA
Report this comment as inappropriate
Apr 17, 2011 @ 5:17 pm
New generation of fungi found in the Northern part of Nigera known as breadin gwado, in english is known as frog's meal.
20
Report this comment as inappropriate
Jun 18, 2011 @ 3:03 am
Thank you for sharing to us.there are many person searching about that now they will find enough resources by your post.I would like to join your blog anyway so please continue sharing with us.
21
Report this comment as inappropriate
Sep 12, 2011 @ 8:08 am
More distinctive features that differentiate between fungi and mould
22
Report this comment as inappropriate
Oct 1, 2011 @ 1:01 am
what are the diseases of lichens,club fungi and cup fungi?
23
Report this comment as inappropriate
Oct 29, 2011 @ 3:03 am
this article proved helpful for my seminar,i would like to receive articles that touches the various methods of preparing slides for fungal organisms.if u could also send me references i would be very grateful to hear from you soon
24
Report this comment as inappropriate
Nov 10, 2011 @ 12:12 pm
thanks this help me a lot and it a great web site so thanks
25
Raven Lee
Report this comment as inappropriate
May 14, 2012 @ 12:12 pm
This was accually really helpful to me , do to the fact that this had the different types of Fungi .
Thanks . (:
26
Frutillita
Report this comment as inappropriate
Sep 26, 2012 @ 11:11 am
Toe fungus?If it's only the nails its nail ringrowm you have, several different fungi grow in the nails, but they are unlikely to spread. Usually the nail becomes, thick and brittle, and can turn yellow. If only a few of your nails are affected, you can treat it with an anti-fungal lacquer from the chemist, try to get one with the active ingredient tioconazole' or amorolfine'. You should use this for at least 3 months. If all the nails are affected you may need an oral anti-fungal such as terbinafine, from your doctor.Now if the infection is between your toes and around the side of your feet it's athlete's foot you have. You can tell this by the burning, intense itching and flaking of the skin between your toes. Their are many anti-fungal creams available over the counter for this infection, they are often combined with a mild antiseptic and a mild steroid to reduce the itching. Remedies such as garlic juice (which contains a powerful anti-fungal agent) and tea tree oil are quite good at clearing this type of infection also. If you need more info visit the source below.
27
cookie
Report this comment as inappropriate
Apr 3, 2013 @ 7:19 pm
Toe fungus is athletes foot never knew until I loooked it up on another website
28
Emmy Jenkins
Report this comment as inappropriate
Dec 1, 2013 @ 4:16 pm
This was very helpful! Maybe do one on the other kingdoms? Thank you so much!
29
AGGREY
Report this comment as inappropriate
May 10, 2015 @ 8:08 am
I would like to know,diffrent phylla of fungi each with examples and economic importance attached to each pyllum.
30
Jasmine
Report this comment as inappropriate
Apr 20, 2016 @ 9:09 am
This helped me with my work thanks for all of your help internet

Comment about this article, ask questions, or add new information about this topic:

CAPTCHA