Chapter 9.4, Problem 3LO

Summary Introduction

To enlist:

The syndromes associated with abnormal sex chromosomes.

Introduction:

Humans 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). Zygote receives 46 chromosomes.

Sometimes due to nondisjunction of chromosome during meiosis the chromosome number fails to separate and abnormal chromosome are fused to form an abnormal zygote Such abnormal chromosome number causes some syndromes like Down syndrome, Klinefelter syndrome, Turner syndrome, Triple X syndrome are associated with sex chromosome.