Question

Assertion : Foetal disorders can be diagnosed by chorionic villi sampling.

Reason : Karyotyping can be done for mitotically dividing cells of chorionic villi.

(a) Both A and R are true and R is the correct explanation of A

(b) Both A and R are true but R is not correct explanation of A

(c) A is true but R is false

(d) A and R are false

Answer 1

Correct option (a) Both A and R are true and R is the correct explanation of A

Explanation :

During early pregnancy, foetal disorders can be diagnosed using chorionic villi sampling. In this technique the physician inserts a narrow. flexible tube through the mother's vagina and cervix into the uterus (guided by ultrasound) and withdraws a small amount of foetal tissue (chorionic villi) from the placenta. Because the cells of the chorionic villi are undergoing rapid mitosis, these cells can be used for karyotyping.