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Fungi

posted Feb 18, 2016, 2:13 PM by Upali Salpadoru   [ updated Sep 13, 2016, 1:00 AM ]

Kingdom Fungi


Largest Mushroom.jpg


             Fig.1 Largest Mushroom.              

Courtsey:  vyperlook.com

This is supposed to be the largest mushroom ever grown. Is it a Plant or something else. It is a Fungi; a different kingdom. The members of this Kingdom range from microscopic moulds and yeast cells to hyphae that grow hidden but exhibit as mush rooms.

They are not plants as they have no chlorophyll and cellulose in cell walls. They cannot be animals as they have cell walls. These cell walls are made of a poly-sacharide called chitin which happen to be present in some animals such as in the exo-skeleton of Arthropoda.




Structure

Most fungi are similar to icebergs as a greater part of it cannot be see. The mushroom canopies that we see are the fruiting bodies or sporophytes developed for asexual  reproduction. The main body is made up of fine threads called hyphae, that remain hidden to the naked eye. This part is called the mycelium.  

           


Fig.2. Diagram of septate hyphae. .(highly magnified)





Although in some fungi the hyphae are divided into compartments with a nucleus in each, in some fungi the whole filament looks a single cell with several nuclei.


Fungi live on some kind of food matter. They cannot synthesize or engulf food as some protists do. They secrete enzymes to digest the food externally and absorb the nutrition.



Fig.3. Non non septate hyphae. (Coenocytic)






Mould 2.jpg














Fig.4 some mould growing on a fruit.


Moulds.


Penicillin is a very well known antibiotic. Alexander Fleming obtained this from a mould that had the same name.These grow on moist bread and other food substances as invisible thread like structures called hyphae




What are the powdery stuff here?






Reproduction.


After the mycelium has grown for a few days they produce the reproductive structures. They are called sporangia.

Sporangium.jpgFig.5. Sporophyte of Mushroom.

Yeast Saccharomyces..


This is a uni cellular fungi. This had been of immense use to man from ancient times. It makes the dough rise in making bread.

Fig 6. Yeast producing buds.


Yeast is typically 3-4μm


Ali.jpg

Fungi

   

   Good !


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Fungi


  Bad!


1.    The most expensive food in the world is a fungi. It is known as ‘Black diamond’ Just a couple of shavings of black truffles from France - known as black diamonds - can cost hundreds of dollars in a restaurant in Paris. White truffles from Italy can cost more than three times as much.” A truffle is the sporophyte of a subterranean Ascomycete fungus that grow attached to the roots of oa trees.,


2.   .They decompose organic matter along with bacteria.


3.     The rising of dough for bread is performed by yeast.This is fermentation.   C6H12O6.[8] One glucose molecule is converted into two ethanol molecules and two carbon dioxide molecules:

C6H12O6 → 2 C2H5OH + 2 CO2

4. They are used in making medicines such as antibiotics and statins.

1.  Fungal spores if landed on moist food start growing spoiling the food.


2 Superficial fungal infections of the skin and nails are relatively common in normal individuals, Athletes foot

3.  Some fungi (mushroom) if eaten can cause immediate death.


4  The molds that grow especially  inside the house cause allergies and asthma on some people.


Normal building materials and furnishings provide ample nutrition for many species of molds, but they can grow and amplify indoors only when there i

s an adequate supply of moisture.   Courtsey. Pubmed.



Supplements


From the New Scientist  of 13th Feb 1916

Paul Stamets  says “We are sitting on a mould mine.”

Courtsey: Fungi Perfecti.

A bracket fungus off birch trees can arry fire.  When this is boiled and stretched you get a fabric . At present only the people in Tansylvania do this. As they are in the shape of a basket people make hats out of it.

The magic mushroom ( psilocybin) had been able to stop a stutter he had been having. Scientist have found that it can stimulate the growth of neurons. Us Defence department has found pharmaceuticals that can act on dangerous viruses and bacteria.

Bees such the juice of some fungi probably to de toxify the poisons they get from insecticides and herbicides.


Comparing Microbes



BACTERIA

FUNGI

VIRUS

1.Movability.

2 Sensitivity.




3.Nutrition.




4.Respiration.







5. Growth.





6.Cells.






7.Reproduction.




8.Excretion.

Some can crawl using pili or even swim using flagella.

They are sensitive to changes in heat, light, nutrients and chemicals.

They secrete enzymes into the food and absorb the nutrients selected by the cell membrane.

Some bacteria use Oxygen just like other organisms. There are others that derive energy  using other chemicals such as su;phur and iron. Some bacteria are capable of fermenting sugar.

As a result of taking in food and building up the body matter the cells grow in size.


Bacteria  cells are surrounded by a cell wall and a cell membrane. They carry nuclear material though not enclosed by a membrane.(Prokaryotic cell)

Matured bacteria reproduce by binary fission.(Asexual)

Some undergo conjugation.(Sexual)

They excrete waste produced due to reactions inside the cell mainly by diffusion.

Most fungi are incapable of any independent movement except for the growth movements.

They grow towards an area rich in nutrients and moisture..



They generally live inside the food. Digestive enzymes are secreted out and the nutrients are absorbed.

Fermentation is the general mode of respiration. Sugar is broken down to to produce alcohol and carbon dioxide giving energy.





The thallus makes body matter and elongates often producing branches.


The mycelium is surrounded by a cell wall made of chitin. In some species they are divided into units by septa.


Fragmentation is the norm.




Mainly by osmosis.

They do not show any movement except for their ability to push their DNA into a living cell.

They can sense the exact living cell in which they can grow.


A Viruses gets food from the host cell for reproduction.


As there are no metabolic activities, (reactions) without a host cell, there is no respiration outside.




These cells also increase in size.



The genetic material is covered with a protein coat called a capsid.





A virus has to enter a living cell to make copies of itself.



They pass any waste produced into the host cell.


(image courtesy of Jeff Benn)

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Another example is the 'Fairy Ring Toadstool' (Its scientific name is Marasmius oreades). This, in contrast to the Clouded Agaric, grows on grassy expanses such as lawns and golf courses. The fungus can be traced by the rings of dark green grass, with the mushrooms fruiting on the outer edge of the ring. The growth of the ring can be traced year on year. If there are no barriers, rings may grow outwards at up to 20 cm per year. This is a fungus which fruits early in the year, in the spring.




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