-ARE CALLED AMPHIBIANS OF PLANT KINGDOM
-Have jacketed sex organ
-Rhizoids are present
-non vascular in nature
-Leafy structure develop in higher group
-have differentiated body design
- no specialised tissue for conduction of water.
- example
funeraria and merchantia
ADOPTATION TO LAND HABITAT
1) DEVELOPMENT OF ORGAN FOR ATTACHMENT AND ABSORPTION OF WATER
Bryophytes don't grows on water as like algae.
They grows on land.
Hence, Rhizoids develop.
Rhizoids function as absorbing and attaching organ.
(Absorb nutrients, remain attached to the plant)
2) protection against desiccation
Thick compact multicellular thallus covers with epidermis
1)As they are in compact form, the total surface area of bryophytes reduces proportionately as per the volume.
Their surface area decreases, hence transpiration also decreases/reduced.
2) epidermis protect from drying effect of air reduces effect of desiccation.
Desiccation- leaf dries up.
Leaf get shrinked.
3) They have a waxy substance over surface called cutin
this waxy substance is waterproof
this reduces the water loss
example : liverworts.
In many liverworts pores are present, also called air pores.
These pores facilitate gaseous exchange; between atmosphere and interior of the thallus.
4) protection of sex organ from injury
Sex organ are - multicellular
- jacketed
Sterile cells encloses the sperm and egg. (Jacket format)
It depicts adaptation to life on land.
Archegonium ensure :-
-protection against mechanical injury.
-give nourishment to fertilised cell.
fertilised cell (embryo) remain inside archegonium (embryo sac).
So, it becomes conducive/easy for fertilised cell to obtain nutrition, food and water from archegonium.
Nucellus:-
- is female gametophyte.
- surround and protect the embryo.
- formed by double fusion
- usually diploid.
Endosperm:-
- surround and give nutrients to embryo
- formed by triple fusion
- usually triploid
BRYOPHYTES CLASSIFICATION
EICHER (1883) termed as 'BRYOPHYES'.
BRYOPHYES is divided into two types
1) hepaticeae
It is again sub-divided to 3 types.
i) merchantiophyta
ii) jungermanniales
iii) anthocerotales
2) mucci or mosses
Mucci also sub-divided to 3 types
i)sphagnales
ii) andreales
iii) brayles
2) ROTHMALER CLASSIFICATION
Rothmaler (1951)
He divided bryophytes into 3 category
1) hepaticopsida (liverworts)
2) anthocerotopsida (hornworts)
3) bryopsida (mosses)
All the best 😀
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