Reproductive Health — BIOLOGY STD 12 Science — Question

Name the genes responsible for making Bt cotton plants resistant to bollworm attack. How do such plants attain resistance against bollworm attacks? Explain.

By which technique are the gene defects identified in a child or fetus treated? Explain with example.

Rajesh was doing gel electrophoresis to purify DNA fragments. Given below is the sketch of the observations of the experiment performed by him.

1. At which end he would have loaded the samples and where?
2. Analyse the reason for different positions taken up by the DNA bands.
3. Elaborate the step he would have followed to visualise DNA bands.

What are the possible types of pollinations in chasmogamous flowers. Give reasons.

Both Down’s syndrome and Turner’s syndrome are examples of chromosomal disorders. Cite the differences between the two.

Differentiate the following and give examples:
Innate and acquired immunity.

Although Mendel published his work on inheritance of characters in 1865, for several reasons, it remained unrecognised till 1900. Explain giving three reasons, why it did take so long.

Explain how biodiversity is important for human.