Question

Write short note on
(a)Sex linkage (b) Crossing over (c)Sex chromosomes (d) Karyotype

Answer 1

(a) Sex linkage: It is the phenomenon that causes the genes on the same chromosome to be inherited together. It does not allow the genes that are present very closely to segregate and are seen together. The progeny produced are more of parental type and fewer recombinants.

(b) Crossing over: It is the exchange of genetic material between two non-sister chromatids of homologous chromosomes that results in recombination or variations during sexual reproduction. It is one of the final stages of meiosis.

(c) Sex chromosomes: The pair of chromosomes present other than the autosomes are called sex chromosomes. This pair decides whether the individual would be male or female. They are either X or Y.

(d) Karyotype: It is the number and appearance of chromosomes in the nucleus in the eukaryotic cell. It is used for the complete set of chromosomes. It includes both the sex chromosomes as well as the autosomes.