AP BIOLOGY

Detailed explanation-1: -Cloning using somatic cell nuclear transfer (SCNT) [ 1]. This procedure starts with the removal of the chromosomes from an egg to create an enucleated egg. The chromosomes are replaced with a nucleus taken from a somatic (body) cell of the individual or embryo to be cloned.

Detailed explanation-2: -The first step in the process of generating embryonic stem cells is to remove the nucleus from an unfertilized egg cell (A).

Detailed explanation-3: -The genetic material of the donor egg cell is removed and discarded, leaving it ‘deprogrammed. ‘ What is left is a somatic cell and an enucleated egg cell. These are then fused by inserting the somatic cell into the ‘empty’ ovum.

Detailed explanation-4: -To make a clone, scientists transfer the DNA from an animal’s somatic cell into an egg cell that has had its nucleus and DNA removed. The egg develops into an embryo that contains the same genes as the cell donor. Then the embryo is implanted into an adult female’s uterus to grow.

Detailed explanation-5: -In SCNT, the egg cell’s single set of chromosomes is removed. It is replaced by the nucleus from a somatic cell, which already contains two complete sets of chromosomes. So, in the resulting embryo, both sets of chromosomes come from the somatic cell.