The plant or animal cells which are having locomotary organelles such as the cilia and flagella, contain spherical bodies called basal granules at the base of cilia and flagella. These are found embedded in the ectoplasm below plasmalemma and are composed of nine fibrils. Each fibril consists of, three microtubules, out of which two enter in the cilia or flagella. The basal granules may contain both DNA and RNA.
Cilia and Flagella:
They are vibratile hair-like narrow protoplasmic processes which are made of four parts-basal body, rootlets, basal plate and shaft. Shaft consists of an external membrane (extension of plasmalemma), a semifluid matrix and an axoneme. Axoneme has nine peripheral doublet fibrils and two central singlet fibrils. Adjacent peripheral doublet fibrils are interconnected (B-A linkers of protein nexin).
They also give out nexin spokes which bear transition junctions near the central proteinanceous sheath around the central fibrils. Subfibre A of each doublet has two bent arms, the outer one with a hook. The central fibrils and side arms of subfibre A are made of dynein protein with ATP-ase activity.
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Cilia are shorter (5-10 pm as compared to 150 pm for flagella), more numerous (number of flagella 1 -4) have, sweeping or pendular movements (flagella have undulatory motion) and beat in a coordinated rhythmic movement (flagella show independent movements).
In both cilia & flagella, the entire assembly is sheathed by a unit membrane which is simply a part of the plasma membrane.
Many animals have cells, the cilia of which serve simply to move materials part the cells.
Vacuoles:
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They are noncytoplasmic sacs which are separated from cytoplasm by a membrane or tonoplast. In young cells the vacuole is absent. Mature cells may have a large central vacuole. The vacuoles are filled with a watery solution of many inorganic and organic substances and gases and are known as cell-sap.
The cell-sap is responsible for maintaining osmotic relations of the cell. Colours of vast majority flowers are chiefly due to the presence of anthocyanin pigments dissolved in the cell sap which determines the particular colour in fruits and vegetables. Vacuoles are absent from cells of bacteria and blue green algae.
(i) Sap vacuoles:
They enclose sap or water with dissolved inorganic and organic substances. A sap vacuole is surrounded by TONOPLAST. Plant cells have usually a single large central vacuole. Animal cells have numerous smal sap vacuoles. Sap vacuoles maintain osmotic pressure for turgidity and osmosis. They also store useful as well as waste substances.
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(ii) Contractile vacuoles:
They occur in some simple fresh water forms (e.g. Amoeba, Paramecium, Chlamydomonas. Contractile vacuoles are surrounded by a few feeding canals. They pick up water from surrounding cytoplasm, expand (diastole) and collapse (systole) to throw water to the outside. Contractile vacuoles perform osmoregulation and excretion.
(iii) Food vacuoles:
It is a complex of lysosomes & phagosome. Digestion occurs inside them.
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(iv) Gas Vacuoles:
(Pseudovacuoles). They occur in some procaryotes. Each gas vacuole is made of a large number of submicroscopic hexagonal gas vesicles. A gas vesicle is surrounded by a thin protein membrane. Gas vacuoles store metabolic gases and take part in buoyancy regulation.