Human Reproduction — BIOLOGY STD 12 Science — Question

Name any two chromosomal aberration associated disorders.

What is spermatogenesis? Briefly describe the process of spermatogenesis.

The following are some well-known abbreviations, which have been used in this chapter. Expand each one to its full form:

1. MALT.
2. CMI.
3. AIDS.
4. NACO.
5. HIV.

A true breeding pea plant homozygous for axial violet flowers is crossed with another pea plant with terminal white flowers (aavv).
List the Mendel’s generalisations that can be derived from the above cross.

Differentiate between homology and analogy. Also discuss the homologous and vestigeal organs with example and how do they explain the evidence of evolution.

Describe the functioning of electrostatic precipitator along with a schematic diagram.

The following is the illustration of the sequence of ovarian events (a – i) in a human female.
Write the difference between ‘c’ and ‘h’.

Answer the following questions: Given below is the T.S. of human ovary. Identify the following in the diagram:

1. Corpus luteum.
2. Secondary oocyte.
3. Antrum.
4. Primary follicle.
5. Blood vessels.

Draw a neat diagram of the female reproductive system and label the parts associated with the following.

1. Production of gamete.
2. Site of fertilisation.
3. Site of implantation.
4. Birth canal.

Vicky's mother was using the same mosquito repellent cream from last six years. She was regularly complaining that this cream has no effects on mosquitoes now. Hearing this, Vicky advised his mother to change the cream as regular usage has led the mosquitoes to develop resistance against it. His mother changed the cream and could notice its effect on mosquitoes.

1. Explain how mosquitoes were not affected by the previous cream?
2. On what factors, Darwin's theory was based?
3. Can you relate this incident to Darwin's concept? How?
4. Identify the values shown by Vicky.