Question Bank [2022] — BIOLOGY STD 12 Science — Question

What is the origin of embryos in adventive polyembryony ?

Define the lifespan of an organism. Mention the lifespan of:

1. Crow.
2. Mayfly.

Which method of recycling of sewage is used in Tirumala hills?

Name the gases released during Bhopal gas tragedy in December, 1984.

Suggest a molecular diagnostic procedure that detects HIV in a suspected AIDS patient.

In a dihybrid cross carried out by T.H. Morgan in Drosophila, the F, ratio deviated from that of Mendel's dihybrid F, ratio. Give a reason.
Or
Why do certain genes tend to be inherited together in a cell at the time of cell division?

Or
If the frequency of a parental form is higher than 25% in a dihybrid test cross, what does that indicate about the two genes involved?

Where does fertilization and implantation occur?

Name the two forms of extinct reptiles that evolved from synapsids.

What is genetic diversity?

What is chimeric DNA?