Zoology: Solved Previous Year Question Paper for NCERT/ CBSE Class 12th Zoology
(Very Short Answer Type Questions)
Question: Write two major functions of the Testes and Ovary.
Answer: Testes:
1. Produces and secretes male sex hormones (androgens) such as testosterone, which are responsible for the development and maintenance of male secondary sexual characteristics.
2. Produces sperm cells, which are essential for reproduction.
Ovary:
1. Produces female sex hormones (estrogens and progesterone) which are responsible for the development and maintenance of female secondary sexual characteristics.
2. Produces ova (eggs), which are essential for reproduction.
Question: Give points of difference between Satellite DNA and Repetitive DNA.
Answer: Satellite DNA and Repetitive DNA are two types of DNA found in the genome of organisms. Points of Difference:
1. Satellite DNA is composed of short, tandemly repeated sequences of DNA whereas Repetitive DNA is composed of longer, interspersed repeats.
2. Satellite DNA is usually associated with centromeres and telomeres whereas Repetitive DNA is found scattered throughout the genome.
3. Satellite DNA is found in higher concentrations in eukaryotic genomes than in Repetitive DNA.
4. Satellite DNA is highly conserved among species whereas Repetitive DNA can vary greatly among species.
Question: Define Immunity. Name its types.
Answer: Immunity is the ability of the body to protect itself from foreign substances, organisms, or toxins.
The three types of immunity are innate immunity, adaptive immunity, and passive immunity.
Question: What do you mean by “Microbial cloning”?
Answer: Microbial cloning is the process of creating a genetically identical copy of a microorganism, such as a bacterium, virus, or fungus, through asexual reproduction.
(MCQ/Objective Type Questions)
(i) Expand the terms ZIFT and GIFT.
Answer: ZIFT: Zygote Intrafallopian Transfer
GIFT: Gamete Intrafallopian Transfer
(ii) Fins and Flippers are homologous organs. (True/False)
Answer: True
(iii) Name the protozoan which causes “Nosema” disease in
(True/False)
Answer: True
(iv) Which of the following is not lymphoid tissue?
(a) Spleen
(b) Appendix
(c) Tonsils
(d) Thymus
(e) Bone
Answer: (e) Bone