Talk to a doctor. Find out how twinning occurs. Look for any twins in your neighbourhood, or among your friends. Find out if the twins are identical or non-identical. Also find out why identical twins are always of the same sex? If you know of any story about twins, write it in your own words.

AcademicBiologyNCERTClass 8

Twins are divided into two parts:-

1. Identical Twins- It is also known as monozygotic as only one zygote is formed. In identical twins, one egg is fertilized by one sperm, but later the embryo splits up to become two.

In this case, the baby can only be a boy-boy or girl-girl.



2. Fraternal Twins- It is also known as dizygotic, as two zygotes are formed. In fraternal twins, two separate eggs get fertilised by two separate sperm independently, and each becomes an embryo.

In this case, the baby can be a boy-boy, girl-girl, and boy-girl.


Updated on 10-Oct-2022 12:46:40