Human Reproduction — BIOLOGY STD 12 Science — Question

The biology teacher asked her students to verify the experiment on transformation principle in bacteria to establish DNA as genetic material. The class was divided into two groups. The teacher asked them to submit the reports. Group 2 did not use mouse and did not repeat Griffith's experiment. The teacher praised them.

1. Which experiment did they perform?
2. Explain the experiment in brief.
3. Who and when performed the transformation principle experiment?
4. What values did students of group 2 exhibit?

Name and state the law that can be derived from this cross and not from a monohybrid cross.

What is cancer? How is a cancer cell different from normal cell? How do normal cells attain cancerous nature?

Answer the following questions.
Explain the events taking place at the time of fertilisation of an ovum in a human female.

Gene expression can be controlled with the help of RNA. Explain the method with an example.

A pregnant woman was adviced to undergo medical termination of pregnancy. Her doctor found that the foetus in her womb was developed from a zygote made of an XX egg fertilized by a Y-bearing sperm? Why was she advised to undergo MTP?

Describe the functions of the following:
Seminiferous tubules.

Explain the steps involved in a polypeptide synthesis. How are the amino acids activated during polypeptide synthesis?