Human Reproduction — BIOLOGY STD 12 Science — Question

What is asexual mode of reproduction?

Retroviruses have no DNA. However, the DNA of the infected host cell does possess viral DNA. How is it possible?

Habitat

Meselson and Stahl experimentally proved the ________ replication of DNA.

Common amides present in plants.

The egg of an animal contains 10 chromosomes, of which one is X-chromosome. How many autosomes would there be, in the karyotype of this animal?

Name the era when birds began to origin.

Given below are the pairs of pathogens and the diseases caused by them. Which out of these is not a matching pair and why?

a.	Virus	Common cold
b.	Salmonella	Typhoid
c.	Microsporum	Filariasis
d.	Plasmodium	Malaria

In which animal Rh factor was discovered at first?

Name the event, during cell division cycle that results in the gain or loss of chromosome.