NCERT: Fungi

Question 1

1). How many heterotrophic kingdoms are there in Whittaker’s system?

2). “The fungi constitute a unique kingdom of heterotrophic organisms”
What makes fungi unique? Discuss nutrition as well.

Answer 1

Fungi and Animalia are two purely heterotrophic kingdoms.

In a stark contrast to animalia, fungal organisms are spore producing , thalloid organisms with chitinous cell walls. (CELL WALL: while absent in animals, chitin+polysaccharide in fungi)
Mostly heterotrophic, Fungal organisms are saprotrophic in nutrition (absorb soluble organic matter from dead substrates), can ve parasites and also symbionts (mycorrhiza and lichens)

Question 2

Give some of the most common fungal examples that even a layman would be familiar with.

a) “fungi seen on moist bread and rotten fruits” 3
b) “common mushrooms we eat and toadstools” 4
c) “some are a source of antibiotics. eg penicillium” 2
d) “white spots on mustard leaves” 1
e) “beer and bread making” 1

Answer 2

2). as mentioned
a) “fungi seen on moist bread and rotten fruits”
rhizopus and mucor (zygomycetes) are the common saprotrophic fungi that attack a variety of food stuffs.
Rhizopus stolonifer/ R. nigricans: black bread mould
Soft rot/leak disease is caused by rhizopus.
Aspergillus: green smoky mould contaminates food stuff including bread, butter, etc. along with laboratory cultures (weed of laboratory). Highly poisonous due to aflatoxins.

b) "common mushrooms we eat and toadstools" Mushrooms are edible and non-edible agaricales (gilled mushrooms, fungal order) which possess umbrella like basidiocarp edible: Agaricus campestris, Agaricus bisporous, Volvariella volvacea (paddy straw mushroom), Pleurotus ostreatus non-edible/poisonous: Toadstools- Amanita caesarea (caesar's mushroom), Amanita phalloides (Death cup), Amanita muscaria (Fly agaric) and Gynomitra esculenta (heat labile carcinogenic toxin)

other edible species:
Morels (sponge mushroom) are ascomycetes with edible ascocarps having fleshy sponge like conical cap or pileus and a stalk like stipe eg. Morchella esculenta (V. guchhi), Morchella deliciosa
Truffels: edible tuber like subterrranean ascocarps, eg. Tuber aestivum

 c) "some are a source of antibiotics. eg penicillium" discovered from P. notatum, commercially from P. chrysogenum RAMYSIN: mucor ramannianus (zygomycetes) Penicillium is also employed in ripening of cheese eg. P. roqueforti and P. camemberti

 d) white spots on mustard leaves: albugo candida (oomycetes)
 e) beer and bread making: yeast

Question 3

1). fungi show great diversity in morphology and habitat.
2). Name the following w/ class:
fungi on moist bread and rotten fruit
common mushroom
toadstools
white spots on mustard leaves
bread and beer making org
source of anitbiotics

Answer 3

1) . unicellular: yeast, synchitrium multi: thalloid body of hyphae (network: mycelium) w or w/o septa
habitat: cosmopolitan (air, water, soil, on animlas and plants), prefer warm and humid places

2). rhizopus and mucor
agaricus
amanita caesaria
albugo candida
yeast
penicillium (notatum: discovered, chrysogenum: commercialised)

Question 4

overlay of reproduction in fungi

Answer 4

rep: 
A). vegetative
-fragmentation (eg penicillium), 
-fission and 
-budding (eg. yeast: saccharomyces octaspoprous and s. cerevisae; formation of pseudomycelium) 

B). asexual: spores
-zoospore (oomycetes)
-sporangiospore (zygomycetes eg rhizopus and mucor)
-conidia (ascomycetes eg penicillium)
EXTRA:
-oidea (zygomycetes eg mucor and rhizopus)
-chlamydospore (rhizopus)

C). sexual spores
-oospore
[extra]-zygospore
-ascospore
-basidiospore

Question 5

description of all asexual spores

Answer 5

*ONLY MOTILE SPORE IS ZOOSPORE

ZOOSPORE:

• endogenous (f/in zoosporangium)*
• uninucleate
• flat naked small

SPORANGIOSPORE:

• endogenous (sporangium)*
• coenocytic
• thin walled

CONIDIA

• exogenous*
• uninucleate, bilayered, blue green***
• basipetal order (youngest at the ‘base’/ point of attachment)
• ultimate branch: metulae
• order: conidiophore>rami>metulae>sterigmata>conidium

[Extra]

OIDEA:

• thin walled spores
• produced in sugar rich conditions in medium
• budding stage: torula

CHLAMYDOSPORE

• unfavourable conditions
• coenocytic
• thick walled resting resistant spore (RFM)
• also perennating structures