NEET BIOLOGY

Detailed explanation-1: -It is important to know that, unlike a multiple embryo transfer, twins that result from a single split embryo transfer often cannot be reduced. Because identical twins will most likely share a placenta, it is usually impossible to remove one fetus to give the other the best chance of a healthy birth.

Detailed explanation-2: -There are 3 types of identical twins. About one-third of identical twins split soon after fertilisation and form completely separate twins. Like fraternal twins, these twins have separate placentas. The other two-thirds split after they attach to the wall of the womb.

Detailed explanation-3: -Splitting of the embryo may occur at any time during the first 2 weeks after fertilization, resulting in several forms of monozygotic twins.

Detailed explanation-4: -Zygotic splitting occurs between days two and six when the zygote divides, usually into two, and each zygote then goes on to develop into an embryo, leading to identical twins (or triplets if it divides into three). These are known as “monozygotic” twins (or triplets).

Detailed explanation-5: -The two types of twins are classified as monozygotic and dizygotic. Monozygotic (MZ) twins, also called identical twins, occur when a single egg cell is fertilized by a single sperm cell. The resulting zygote splits into two very early in development, leading to the formation of two separate embryos.