Take a seed and break it open. There is no plant
inside the seed. Similarly, if you break open an egg, there is no chick inside.
But the seed when sown in soil and watered, gives a plant which may grow into a
tree. Similarly, the egg, when incubated, gives a chick. have you ever thought
how this is possible?
The cells produced from the egg or zygote are of two
types. Vegetables or somatic cells and reproductive or germ cells. Various
organs in the body are derived from these two cell types.
As you can see, the germ cell give rise to organs
involved in the production of male and female gametes while the somatic cells
give rise to almost all the organs except those producing male and female
gametes. These cells that divide are called parental or mother cells and the
resulting cells i.e the products of cell division are called daughter cells.
All the somatic cells divide by a process of mitosis
while the germs cells divide by a process called meiosis or reduction division. The major difference between the mitosis and meiosis
is the number of chromosomes in the daughter cells.
In mitosis, daughter cells have exactly the same
number of chromosomes as the parental cell..
In meiotic division, daughter cells have exactly
half the number of chromosomes of the parental cell cells.
Details about mitosis and meiosis and how they occur
are given in the next two videos.
THANKYOU,
NANDITHA AKUNURI
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