Inbreeding depression is the reduction in the fertility and productivity of an organism due to continuous inbreeding. Inbreeding is the mating of closely-related individuals within the same breed for 4-6 generations. Continued inbreeding, especially close inbreeding usually reduces the fertility and even productivity of the organism. Two advantages of inbreeding are:
(i) Superior quality of breed of organisms is obtained.
(ii) Pure lines can be developed.
(a) Draw a labelled diagram of the human female reproductive system.
(b) Enumerate the events in the ovary of a human female during:
(i) Follicular phase
(ii) Luteal phase of menstrual cycle
How can crop varieties be made disease resistant to overcome food crisis in India? Explain.
Name one disease resistant variety in India of:
(a) Wheat to leaf and stripe rust
(b) Brassica to white rust
(a) Identify (A) and (B) illustrations in the following:
i.
ii.
(b) Write the term given to (A) and (C) and why?
(c) Expand PCR. Mention its importance in biotechnology.
(a) Sickle celled anaemia in humans is a result of point mutation. Explain.
(b) Write the genotypes of both the parents who have produced a sickle celled anaemic offspring.
The diagram above is that of a typical biogas plant. Explain the seQ uence of events occurring in a biogas plant. Identify a, b and c.
Name the type of interaction seen in each of the following examples:
(i) Ascaris worms living in the intestine of human
(ii) Wasp pollinating fig inflorescence
(iii) Clown fish living among the tentacles of sea-anemone
(iv) Mycorrhizae living on the roots of higher plants
(v) Orchid growing on a branch of a mango tree
(vi) Disappearance of smaller barnacles when Balanus dominated in the Coast of Scotland.
Write the source and the effect on the human body of the following drugs:
(i) Morphine
(ii) Cocaine
(iii) Marijuana
The base sequence in one of the strands of DNA is TAGCATGAT.
(i) Give the base sequence of its complementary strand.
(ii) How are these base pairs held together in a DNA molecule?
(iii) Explain the base complementarity rules. Name the scientist who framed this rule.
