The greatest influence on a stable ecosystem in nature is exerted by

A. man

B. pollution

C. animals

D. rainfall

The physical space occupied by an organism together with its functional role in community can be described as

A. environment

B. biome

C. niche

D. habitat

A freshwater pond may contain

A. tadpole, water boatman, leeches and crab

B. water beetle, shrimps, water snail and water bug

C. water lily, fish, water scorpion and dragon larva

D. pon skater, water lily, shark and mosquito larva

The hygrometer is used for measuring

A. relative humudity

B. specific gravity

C. rainfall

D. salinity

The distribution of plants in a rain forest is governed mainly by

A. vegetation

B. soil types

C. amount of sunlight

D. rainfall pattern

Both recessive and dominant characters are found

A. on different chromosomes in the cell

B. at the same locus of a homologous chromosome

C. at different loci of a homologous chromosome

D. on the same chromatid in a chromosome

The probability of a baby being a boy or a girl depends on the contribution of the

A. father's sex cell

B. father's somatic chromosome

C. mother's sex cell

D. mother's X-chromosome

Which of the following statements is true of blood groups and blood transfusion?

A. Group O is the universal recipient

B. Group A can donate to group A only

C. Group AB is the universal recipient

D. Group B can donate to group B only

Which of the following is likely to encourage inbreeding in plants?

A. Dioecious

B. Protandrous

C. Monoecious

D. Hermaphrodite

A tall plants crossed with a dwarf one produces offspring of which half are tall and half are dwarf. What are the genotypes of the parents?

A. TT, TT

B. Tt, tt

C. TT, tt

D. Tt, Tt