Human Reproduction — BIOLOGY STD 12 Science — Question

Match Column I with Column II.

S. No.	Column I	S. No.	Column II
A.	Acrosome	1.	Motility of sperm towards the egg.
B.	Head	2.	Powerhouse of the sperm; contains a number of mitochondria.
C.	Tail	3.	Contains the genetic material.
D.	Middle piece	4.	Contains enzymes to dissolve egg envelopes.

What is the name of network formed by the fusion of open ends of seminiferous tubules? Where does this network lead to?

What is a test cross? How can it decipher the heterozygosity of a plant?

A large number of married couples the world over are childless. It is shocking to know that in India the female partner is often blamed for the couple being childless.
State any two reasons responsible for the cause of infertility.

Many plant and animal species are on the verge of their extinction because of loss of forest land by indiscriminate use by the humans. As a biology student what method would you suggest along with its advantages that can protect such threatened species from getting extinct?

 In which phase of menstrual cycle is corpus luteum formed?

Transgenic animals are the animals in which a foreign gene is expressed. Such animals can be used to study the fundamental biological process, phenomenon as well as for producing products useful for mankind. Give one example for each type.

How is the entry of only one sperm and not many ensured into an ovum during fertilisation in humans?

What are satellite DNA in a genome? Explain their role in DNA fingerprinting.

Removal of gonads cannot be considered as a contraceptive option. Why?