Question

what procedure is used to obtain embryonic or fetal chromosomes for karyotyping?
a chorionic villi sampling (cvs)
b ultrasonography
c amniocentesis
d either chorionic villi sampling (cvs) or amniocentesis are used

Explanation:

• Chorionic villi sampling (CVS): It involves taking a sample of the chorionic villi (tissue from the placenta) which contains fetal cells. These cells can be used for karyotyping.
• Amniocentesis: A sample of amniotic fluid (which contains fetal cells shed from the skin and other tissues) is taken. The fetal cells in the amniotic fluid can be cultured and then used for karyotyping.
• Ultrasonography: It is an imaging technique that uses high - frequency sound waves to create images of the fetus. It does not provide cells for karyotyping.

Since both CVS (which samples placental tissue with fetal cells) and amniocentesis (which samples amniotic fluid with fetal cells) can provide cells for karyotyping, while ultrasonography cannot.

Answer:

D. Either chorionic villi sampling (CVS) or amniocentesis are used