Plant Water Relation — BIOLOGY STD 12 Science — Question

Would the extinction of one insect pollinator affect the ecosystem? Explain.

The evolutionary story of moths in England during industrialisation reveals, that 'evolution is apparently reversible'. Clarify this statement.

Give a scientific term for the following sentences:

1. Total number of individuals of a species in an area.
2. A surgical procedure performed on males in which the vas deferens are cut and tied is known as:
3. A contraceptive device consisting of a small thimble-shaped cup that is placed over the uterus to prevent the entrance of spermatozoa.
4. Removal of gonads, often referring to the removal of male testes is called.

Name the country where industrial melanism was observed in moths due to industrialization.

Nature trails, Pollination, Sea food, Carbon sequestration, Animal therapy, Pest control, Health care, Nutrient cycling.

Column A	Column B
(1) Supporting services	________________
(2) Provisioning services	________________
(3) Regulating services	________________
(4) Cultured services	________________

Give the term for each of the following:

1. The condition in which both male and female reproductive organs are found on the same plant.
2. The condition in which both male and female parts are present on the different plants.
3. Animals that remain reproductively active throughout their reproductive phase.
4. Animals that remain reproductively active only during the favourable seasons in their reproductive phase.

Which kind of immunity, active or passive, is produced by vaccination? Name the disease against which protection is provided by BCG vaccine.

Name the two most commonly employed hosts and the vectors for human gene cloning.

Show DNA replication with the help of a diagram only.