Molecular Basis of Inheritance — BIOLOGY STD 12 Science — Question

The corona radiata of an ovum acts as a barrier for the penetration of sperms. How do sperms overcome this barrier?

Who developed the technique of electrophoresis? Write the principle on which it is based.

State the ploidy of gametes, if parent body is haploid.

Tell the host and place where the following stages in the life cycle of malaria parasite occur
(a) Formation of gametocyte
(b) Fusion of gametocyte.

Suggest the breeding method most suitable for animals that are below average in milk productivity.

What is common about Eichhornia, Lantana and Parthenium with reference to threat to our biodiversity?

Recently chikungunya cases were reported from various parts of the country. Name the vector responsible.

Name the two intermediate hosts on which the human liver fluke depends to complete its life cycle so as to facilitate parasitisation of its primary host.

State the chromosomal defect in individuals with Turner's syndrome.

Why is it essential to have a 'selectable marker' in a cloning vector?