Question

Absence of one sex chromosome causes

• A. Turner's syndrome
• B. Klinefelter's syndrome
• C. Down's sundrome
• D. Tay-Sach'ssyndrome

Answer 1

The correct option is A Turner's syndrome

Absence of one sex chromosome causes Turner’s syndrome. This disorder is due to monosomy (2n-1). It appears due to fusion of abnormal egg (22 + 0) and a normal sperm (22 + X) or a normal egg (22 + X) and abnormal sperm (22 + 0). People suffering from Turner’s syndrome have 45 chromosomes instead of 46 chromosomes. Such females are sterile as ovaries are rudimentary besides other features including lack of other secondary sexual characters.