Question

Genes are the physical basis of heredity. How are chromosomes, genes and
DNA connected? Explain.

Answer 1

During reproduction ,after fertilization the single cell formed or the zygote keeps on dividing to lead to the formation of a new individual.When the zygote divides,the nucleus also divides and hence the chromosomes also divide to form two diploid cells.Chromosomes are made up of nucleotoid strands or DNA-deoxyribonucleac acid.Genes are located on these DNA strands which determine the physical characteristics as well as gender

Answer 2

Mendel’s work suggested that traits are inherited independently of each other. Morgan identified a 1:1 correspondence between a segregating trait and the X chromosome, suggesting that the random segregation of chromosomes was the physical basis of Mendel’s model. This also demonstrated that linked genes disrupt Mendel’s predicted outcomes. The fact that each chromosome can carry many linked genes explains how individuals can have many more traits than they have chromosomes. However, observations by researchers in Morgan’s laboratory suggested that alleles positioned on the same chromosome were not always inherited together. During meiosis, linked genes somehow became unlinked.