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Preksha Dhyana :
somes. One of each pair of formerly jointed chromosomes are dragged outward in the opposite directions. In the next phase the chromosomes lose their discrete shapes, reforming the tangled mass. A pinching in the cell membrane along the equator of the old cell appears and deepen progressively until the old cell separates into two replicas, each surrounded by its own complete cell membrane. Various organelles have been distributed also. Thus when division is completed, two fully equipped, functioning cells have been produced, ready to grow and to divide again.
The deoxyribonucleic acid (DNA) is the dictator of all cells controlling their behaviour by ordering their constituents what to make, what to seek and what to avoid. It can be compared to an architect who designs, draws up plans and prepares blueprints for a building. Actual construction is carried out by contractors ribonucleic aicd— RNA
The divison that commenced in the womb continues throughout life. Millions of cells die and millions are born by the process of division, each producing two new ones which are exact duplicates of the mother cell. The exception to this constant replacement are brain cells called Beurons. Worn out and damaged neurons keep dying without replacement. We shall learn more about neurons in the next chapter. Chemistry of Life
Each living cell contains thousands of different kinds of chemicals. These chemicals are not an inert mixture but are constantly interacting with one another. The blue-prints of heredity are encoded in chemical from. The structures of the body are built up from chemical constituents, and differences in chemical composition distinguish one type from another.
To sum up, cells participate in every function of the body from birth to death. It is really a supreme wonder how 60 billions of them live in such harmony, each one performing its own assigned duty.
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