Q14 of 30 Page 1

Give reasons for the following:

(a) The human testes are located outside the abdominal cavity.


(b) Some organisms like honey-bees are called parthenogenetic animals.


a. Human testes are located outside the abdominal cavity because the production of sperm (spermatogenesis) requires a temperature that is 2-2.5°C less than the body temperature.

b. Drones of honeybee hatch from unfertilized eggs as they develop directly from the female gamete without fertilization. This is why they are called as parthenogenic animals.


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(b) Why is this method of selection referred to as “insertional inactivation”?


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OR


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