Batrachospermum Occurrence:- (1) Batrachospermum is fresh water alga. (2) It is found in clear, cool, and running streams. (3) Deepwater plants are dark violet or reddish in color. But the shallow-water species are olive green. (4) The intensity of light changes the color of pigments. (5) The thallus is attached to the substratum. Vegetative structure (1) The thallus of an adult plant is soft, thick, filamentous. (2) It is freely branched and gelatinous. (3) The central axis is made up of a single row of large cells. Whorls of branches of limited growth are developed on this axis. (4) These branches are filamentous and dichotomously arranged. (5) The main axis is corticated. It consists of a row of elongated cylindrical cells....
Endoplasmic
reticulum :-
The
electron microscopic membrane bound system
present
in the cytoplasm is called endoplasmic reticulum
It
is reported by porter in 1945,it connects the nucleus to the one end and other
end is connected by cell membrane. It has two parts :-
(1)Smooth
endoplamic reticulum
(2)
Rough endoplamic reticulum.
ER
Contains Cisternae,tubules abd vesicles
 |
| Endoplasmic Reticulum |
Cisternae :-
These
are long, flat and un-branched plates or lamellae arranged in parallel rows.
(b) Vesicles:-
They
are usually round or ovoid sacs. They often occur isolated in the cytoplasm.
(c) Tubules:-
They
are irregularly branched tube-like structures having a diameter of 50-100n.
These are surrounded by this unit membrane of 50-60 thickness and their lumen
is filled with the secretary products of the cell.
Smooth endoplasmic reticulum :-
The
SER is smoothly surface ER but RER contain ribosomes on its surface so its appearance
is roughly type .
(A)Common to both Endoplasmic
Reticulum:-
(i)
Forms the skeletal framework.
(ii)
Active transport of cellular materials.
(iii)
Metabolic activities due to presence of different enzymes.
(iv)
Provides increased surface area for cellular reactions.
(v)
Formation of nuclear membrane during cell division.
(B) Function of Smooth
Endoplasmic Reticulum:-
(i)
Lipid
synthesis.
(ii)
Glycogen synthesis.
(iii)
Steroid synthesis like cholesterol, progesterone, testosterone, etc.
(iv)
Metabolism of carbohydrates .
(v)
Detoxification function.
(vi)
Major storage and released site of inter cellular calcium ions.
(c) Function of Rough
Endoplasmic Reticulum:-
(i)
It provides site for protein synthesis.
(ii)
Protein translocation, folding and transport of protein.
(iii)
Glycosylation (this is the relation of a saccharides group with a hydroxyl or
amino functional group to form a glucoside).
(iv)
Disulfide bond formation (disulfide bonds stabilize the tertiary and quaternary
structures of many proteins).
(v)
Membrane synthesis.
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