Chapter 9.4, Problem 3CYP

Summary Introduction

To distinguish:

The chromosomal abnormality in sex chromosome and autosome.

Introduction:

Humans cell contain 46 chromosome (2n) and are diploid in nature but at the time of fertilization only 23 (n) chromosome is receive by mother and 23 (n) chromosome is receive by father to form a zygote by the process of meiosis. Zygote is formed by the transfer of male gamete (sperm) and female gamete (ova).

The ova and sperm are haploid and form a diploid zygote (2n). Zygote receives 46 chromosomes. Some humans are born with abnormalities as they receive abnormal chromosomal number in their cell.

Abnormal chromosome is formed when chromosome fails to separate during meiosis and is known as nondisjunction. In normal individual, 46 chromosomes are present out of which 23 are from male and 23 from female. In which 22 pairs are autosome and 23 is sex chromosomes. So some disorders are also associated with the autosome and are called autosomal disorder.