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....
Microbodies :-
Many membrane bound minute vesicles called microbodies
that contain various
enzymes, are present in both plant and animal cells.
Cilia and Flagella :-
 |
| Internal structure of Cilia |
Cilia (sing.: cilium) and flagella (sing.: flagellum) are
hair-like outgrowths of the cell membrane. Cilia are small structures which
work like oars, causing the movement of either the cell or the surrounding
fluid.
Flagella are comparatively longer and responsible for cell movement.
The
prokaryotic bacteria also possess flagella but these are structurally different
from that of the eukaryotic flagella.
The electron microscopic study of a
cilium or the flagellum show that they are covered with plasma membrane.
Their
core called the axoneme, possesses a number of microtubules running parallel to
the long axis.
The axoneme usually has nine pairs of doublets of radially
arranged peripheral microtubules, and a pair of centrally located microtubules.
Such an arrangement of axonemal microtubules is referred to as the 9+2 array
,
The central tubules are connected by bridges and is also enclosed by a central
sheath, which is connected to one of the tubules of each peripheral doublets by
a radial spoke.
Thus, there are nine radial spokes. The peripheral doublets are
also interconnected by linkers. Both the cilium and flagellum emerge from centriole-like
structure called the basal bodies.
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