Molecular Basis of Inheritance — BIOLOGY STD 12 Science — Question

 A DNA molecule in which both strands have radioactive thymidine is allowed to duplicate in an environment containing non-radioactive thymidine. What will be the correct number of DNA molecule that contain some radioactive thymidine after 3 duplications?

A male honeybee has 16 chromosomes whereas its female has 32 chromosomes. Give one reason

Mention the useful as well as the harmful drug obtained from the latex of poppy plant.

Of the eight nuclei formed in the embryo sac, six become organised into cells.

1. What term is given to the other two nuclei?
2. Name the cell in which they are present.

The carbon atoms fixed by producers have to pass through three species. Mention the trophic level of the third species.

Bring out one main difference between CuT and LNG–20.

Write the phenotypic ratio of Mendel's dihybrid cross?

When was Ramsar Convention developed and adopted and when did it come into force?

Mention the primary aim of the ARTs.

Pick out the ancestral line of Angiosperms from the list: Conifers, Seed ferns, Cycads, Ferns.