GENERAL ACCOUNT

FUNGI

Submitted to: Miss Samina Hassan

Submitted by: Aneequa sadaf

Anum khan

Major/Semester: Biotechnology IV

MYCOLOGY

The branch of botany which deals with fungi is called

Mycology, derived from Greek word Mykes (mushrooms)

General Characteristics

Eukaryotic organisms with cell wall made of chitin or cellulose

Lack chlorophyll

Filamentous body consisting of septate and non-septate hyphae

Non-motile

Heterotrophic organisms

Reproduce sexually or asexually by means of spores

OCCURRENCE AND HABITAT

Fungal kingdom is a large one containing

50,000 to 100,000 known species.

Fungi are universal in their distribution.

Many of the fungi are terrestrial, some

are aquatic and many of them grow on

our food stuffs such as bread, jams,

pickles, fruits and vegetables.

They prefer to grow in dark and dim light

in moist habitats.

MODE OF NUTRITION

They digest food externally by secreting hydrolytic

enzymes onto the food making it soluble so that it can

easily be digested into their cells

They may be saprophytes or parasites

Based on their mode of nutrition

Saprophytic fungi

Absorbs nutrients from

wastes and dead organic

matter.

Parasitic fungi

Obtain food from plants and

animals, causing diseases.

PLANT BODY

A hyphae is made of a thin transparent, tubular wall filled or lined with a

layer of protoplasm varying in thickness

Some fungi are unicellular while

majority are multicellular

Plant body is a thallus

Thallus consists of microscopic

thread like structure filaments

that branch in all directions. Each

of these filaments are known as

hyphae.

Hyphae is the structural unit of the

thallus

HYPHAE

The protoplasm in the hyphae of most filamentous fungi

is interrupted at regular intervals by partitions or cross

walls that divide each hyphae into compartments or

cells, these walls are called septa

Simpler fungi Complex fungi

MYCELIUM

A mass of more or less loosely interwoven hyphae,

constituting the vegetative body of most of the true fungi

Intercellular mycelium

Intracellular mycelium

CELL STRUCTURE

PLECTENCHYMA

During certain stages in the life of some higher forms,

mycelium gets organized into a loosely or compactly

woven tissue like structure, termed as Plectenchyma

Prosenchyma PseudoparenchymaPlectenchyma

o Hyphae are loosely

interwoven and lie

more or less parallel to

each other.

o Hyphae are

longitudinally oriented

and cells are clearly

distinguished.

o Hyphae are closely

packed and interwoven

so that they completely

loose their identity.

o Appear as isodiametric

cells giving the tissues a

parenchyma-like

appearance

DIAGRAMATIC REPRESENTATION

Prosenchyma Pseudoparenchyma

MICROSCOPIC REPRESENTATION

PLECTENCHYMA

Stroma

•Mattress or a pad like compact somatic

structures.

•Reproductive structures of fructification are

formed in or on them.

Sclerotium

•More or less rounded or cushion shaped resisting

bodies formed from pseudoparenchyma

•Able to survive unfavourable conditions of

drought and cold after which they form new

mycelia or external fruiting structures.

MODIFICATIONS OF FUNGI

Rhizomorphs Appressoria Haustoria

HYPHAL TRAPS

Vegetative

reproduction

REPRODUCTION

• Holocarpic fungi: Entire thallus is converted

into one or more reproductive structures

• Eucarpic fungi: Only a portion of the thallus is

converted into reproductive organs while the

rest performs normal vegetative activities

Asexual

reproduction

Sexual

reproduction

VEGETATIVE REPRODUCTION

FRAGMENTATION

The mycelium breaks into two or more similar fragments either

accidentally or due to some external force. Each fragment grows into a

new mycelium.

FISSION

An unicellular organism splits into two

by constriction of the nucleus and the cells.

BUDDING

A new cell is formed from a small outgrowth on the parent cells

VEGETATIVE REPRODUCTION

Fragmentation Fission Budding

ASEXUAL REPRODUCTION

Occurs by means of asexual spores. Sporangiopores or Conidia

Normally occurs under favourable conditions

Several generations are produced in one season

Dispersal of spores occurs through wind, water, insects and

other animals

Polymorphic fungi are those which produce as many as four types of

spores

SPORANGIOPORES

These are produced in special sac like structures, the

sporangia

These are of two types

• Aplanospores

o These are non-motile

o They are unicellular bodies and

are disseminated by wind currents

• Zoospores

o These are motile and flagellated

o Flagellla maybe of whiplash and

tinsel type

CONIDIA

These are non-motile, one to many celled, hyaline or coloured

and produced singly or in groups asexual spores.

They are not contained within membrane.

Conidiogenous cell is the hyphal cell from which or in which a

conidium is formed.

Blastic conidia is formed when a whole conidiogenous cell or a

part of it is transformed into a conidia.

In genera such as Ustilago, the

hyphal cells are directly converted

into thick walled round resting

spores called chlamydospores

Depending upon their position on

the hyphae, chlamydospores may

be terminal, intercalary or lateral.

In genera such as Oospora, the

hyphae gets segmented into

rectangular and thick walled cells

called Arthrospores.

REFERENCES

https://www.boundless.com/biology/fungi/characteristic

s-of-fungi/cell-structure-and-function/

http://www.powershow.com/view/148dca-

MTA5N/Kingdom_Fungi_powerpoint_ppt_presentation

http://www.tutorvista.com/content/biology/biology-

iii/kingdoms-living-world/fungal-reproduction.php

http://www.gitam.edu/eresource/environmental/em_mar

uthi/fungi.htm

A Textbook Of Botany - Vol 1, 11E

By P S Trivedi S N Pandey, P S Trivedi S N Pandey,

Pandey, S N & Trivedi, P S

Textbook of Fungi

By O.P. Sharma

A Textbook of Fungi

By Rajni Gupta

THANK YOU