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Reproductive Health — BIOLOGY STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYReproductive Health1 Mark
MCQ
For two statements are given$-$one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion: Fetal chromosomal disorders can be diagnosed by chorionic villi sampling.
Reason: Karyotyping can be done for mitotically dividing cells of chorionic villi.
  • ✓
    Both assertion and reason are true, and reason is the correct explanation of assertion.
  • B
    Both assertion and reason are true, but reason is not the correct explanation of assertion.
  • C
    Assertion is true, but reason is false.
  • D
    Both assertion and reason are false.
✓

Answer

Correct option: A.
Both assertion and reason are true, and reason is the correct explanation of assertion.
During early pregnancy, fetal chromosomal 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 fetal tissue $($chorionic villi$)$ from the placenta. Because the cells of the chorionic villi are undergoing rapid mitosis, these cells can be used for karyotyping.

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