Chapter 12, Problem 8STP

Summary Introduction

Introduction :

Klinefelter syndrome is a genetic condition that results when a male child is born with an extra copy of the sex chromosome that inherited from his mother. Klinefelter syndrome is not diagnosed until adulthood.

Answer to Problem 8STP

Correct answer :

The correct answer is option (C) XXY.

Explanation of Solution

Explanation/justification for the correct answer :

Option (C) XXY. Klinefelter syndrome can be caused by one extra copy of the Xsex chromosome in each cell (XXY) of the male child. Thus, this is the correct answer.

The explanation for the incorrect answer :

Option (B) OY. OY is a disorder of the sex chromosomes in males which have no X chromosome in their cell. Instead of XY, it has only Y or OY chromosomes. Thus, this is an incorrect option.

Option (C). XO. XO is a disorder of the sex chromosomes, occurring in females, in which one of the two X chromosomes is completely or partially absent. It is called Turner’s syndrome.Thus, this is an incorrect answer.

Option (D). XYY. It is a genetic disorder. In this disorder, male child is born with one extra Y chromosome (XYY). Thus, this is an incorrect answer.