fungus chapter8

7/21/2019 Fungus Chapter8

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Fungus

A Fungus is an eukaryotic organism

that digests its food externally and absorbsthe nutrient molecules into its cells. Fungiare the primary decomposers of deadorganic matter in most terrestrial (长在陆地上的) ecosystems.

Besides that, fungi are used extensively

by humans: yeasts are responsible forfermentation 发酵 of beer and bread,and mushroom farming and gathering is alarge industry in many countries.

Fungus cells have cells wall thatcontain chitin, unlie the cell walls of

plants, which contain cellulose. !hese andother di"erences show that the fungi form asingle group of related organisms,named the Eumycets (true fungi), thatshare a common ancestor(a monophyletic单细胞 group).

Fungi may be single#celled ormulticellular. $ulticellular fungi arecomposed of networks of long hollowtubes called hyphae. !he hyphae oftenaggregate in a dense networ nown asmycelium. !he mycelium grows through

the medium on which the fungus feeds.

http://en.wikipedia.org/wiki/Cellulose

http://en.wikipedia.org/wiki/Common_ancestor

http://en.wikipedia.org/wiki/Monophyletic

http://en.wikipedia.org/wiki/Common_ancestor

http://en.wikipedia.org/wiki/Monophyletic

http://en.wikipedia.org/wiki/Cellulose



Because fungi are embedded in the mediumin which they grow, are often not visible bynaed eye.

%hitin in Fungi

Scientic classication

Kingdom: Fungi



Domain: Eukaryota

Phylum: Basidiomycota

Species: Amanita Muscaria



&east

&easts and other unicellular fungi canreproduce by budding, or 'pinching o a new cell. $any multicellular speciesproduce variety of di"erent asexual sporesthat are easily dispersed and resistant toharsh environmental conditions. hen the

conditions are right, these spores willgerminate and coloni*e new habitats.

!he ecological function and biodiversityof yeasts are relatively unnown comparedto those of other microorganisms. Besidesthat, yeasts, have been found living in

betweens people+s toes as part of their sinora. &easts are also present in the gut oraof mammals and some insects and evendeep#see environments host an array of yeasts.

&east source of energy comes from

glucose. -n the presence of oxygen, it



carries out cellular respiration to brea downglucose, forming carbon dioxide and water.-n the absence of oxygen, glucose in broen

down into carbon dioxide and alcohol. !heprocess in which alcohol is produced fromthe breadown of glucose by yeast is nownas fermentation. %arbon dioxide producedduring this process can be used for maingcae and bread. ine can be prepared from

the fermentation of fruit uice, wheat or ricegrains.



/enicillium

/enicillium grows mostly on fruits such

as lemons. -ts hyphae consist of

Septa(cross walls sing: septum). -tsconidrophore branches with the tips of

conidium can be spread by wind to suitable

substrate of food. /enicilin is an antibiotic

that can be extracted from the fungus

/enicillium notatum and can be used to

inhibit the growth of bacteria.



Besides that, penicillium species are

present in the air and dust of indoor

environments, such as homes and public

buildings. !he fungus can be readily

transported from the outdoors, and grow

indoors using building material or

accumulated soil to obtained nutrients for

growth. /enicillum growth can still occur

indoors even if the relative humidity is low,as long as there is su0cient moisture

available an o given surface.



/enicillium

1cienti2c %lassi2cation

3ingdom : Fungi4ivision : Ascomyeota

%lass : 5urotiomycetes6rder : 5urotiales

Family : !richocomacea 7enue : /enicillium



$ould

hen food, leather or wood are placed in

dar and moist surroundings, mould will

grow on it. $ould is formed from a networ

of 2laments nown as hyhae. 1ome hyphae

grow upwards and the tips of the hyphae

enlarge to form a spherical structure nown

as the sporangium. 5ach sporangiumconsists of numerous spores. 1ome of the

hyphae penetrate into the substrate to get

nutrients.

8hi*opus (bread mould)

8hi*opus grows on moist bread. hen it

matures, the sporangium becomes blac in

colour and bursts open. hen the spores

are dispersed on the other parts of the moist

bread the new hyphae will grow. !his action

when repeated an cause the whole piece of

bread to be covered with mould. Besides,

spores can also be dispersed by wind.



/enicillium

%hrysogenum


3ingdom : Fungi4ivision : Ascomyeota

%lass : 5urotiomycetes6rder : 5urotiales

Family : !richocomacea 7enue : /enicillium

1pecies : /. chrysogenum



8hi*opus


3ingdom : Fungi

6rder : $ucorales

Family :$ucoraceae

7enus : 8hi*opus

1pecies : 8.stolonifer

fungus chapter8

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