Question

Which of the following is true about the two members of a homologous pair?

A. they are identical DNA molecules

B. they form the two sides of one double helix;

C. they separate from one another during meiosis II.

D. they contain the same gene loci in the same order

E. two of these are true.

Answer 1

a)Homologous chromosome have 2 similar chromosome but not identical information, because each set come from both parents which have similar length, location of centromere also position of genes.

b) actual bundles of DNA are called chromosomes. DNA double strand are shorten into a single rod is known as sister chromatids.

c) meiosis occurs in 2 parts that are meiosis1 and meiosis2. in 1st part, reduction division takes place and each daughters cells carry half number of chromosome that contains pir of chromatids also crossing over takes place between homologous chromosomes.

2nd par is same as mitosis. in this part chromatids of sister chromosomes are not identical any more due to recombination in meiosis 1. therefore sister chromatids separate and 2 daughter cells are formed having haploid chromosome number.

d) homologous pair contain same gene at same locus but may be different alleles, because each sets of chromosomes comes from both father and mother. one is paternal chromosome and other is maternal chromosome.