(a) What are chromosomes ? (b) Explain in brief how stability of DNA content of a species is ensured in…
(a) What are chromosomes ? (b) Explain in brief how stability of DNA content of a species is ensured in sexually reproducing organisms ?
Solution
(a)
Chromosomes carry genes which control the traits of an
organism/chromosomes contain information for inheritance of
features from parents to next generation in the form of DNA(Deoxy
ribonucleic acid) molecule.
(b)
• Each cell has two copies of each chromosome, one from
male and the other from female parents which get halved
during the formation of germ cells/gametes.
• After fusion of the germ cells zygote is formed which
restores the normal number of chromosomes and the same
amount of DNA in the progeny.
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