Reproductive Health — BIOLOGY STD 12 Science — Question

How did the process of RNA interference help to control the nematode from infecting roots of tobacco plants? Explain.

Explain the basis on which the gel electrophoresis technique works. Write any two ways the products obtained through this technique can be utilised.

Explain the significance of satellite DNA in DNA fingerprinting technique.

In a monohybrid cross of plants with red and white flowered plants, Mendel got only red flowered plants. On self-pollinating these F₁ plants got both red and white flowered plants in 3 : 1 ratio. Explain the basis of using RR and rr symbols to represent the genotype of plants of parental generation.

1. Identify (A) and (B) illustrations in the following:

1.  

2.  

2. Write the term given to (A) and (C) and why?
3. Expand PCR. Mention its importance in biotechnology.

A person has been diagnosed to be HIV⁺.

1. Name the disease and the test which the person has to undergo.
2. Write the full name of the pathogen involved and describe its structure.
3. Which particular cells of this person are likely to get destroyed?

OR

The immune system of a person is suppressed. In the ELISA test, he was found positive to a pathogen.

1. Name the disease the patient is suffering from.
2. What is the causative organism?
3. Which cells of the body are affected by the pathogen?

Mark the odd one the following groups.
Luteinizing hormone, Progesterone, Chorionic gonadotropin, Estrogen.

Write the sex chromosomal complement of the following:

How are the following used in biotechnology?

1. Plasmid DNA
2. Recognition sequence
3. Gel electrophoresis

Female reproductive organs and associated functions are given below in column A and B. Fill in the blank boxes.

Column A	Column B
Ovaries	Ovulation
Oviduct	A
B	Pregnancy
Vagina	Birth