Year 11

Cloning Gap Fill:

Cloning might occur to produce more of an endangered species, or to maintain a high quality of livestock in farming.

There are two ways in which animal cells can be cloned:

Animal embryo transplants

An cell is taken from the “best” female animal (ie one with desirable qualities). This cell is then by a sperm cell from the “best” male animal to form a , which quickly becomes an embryo The embryo is initially composed of cells, which are unspecialised cells Before these cells specialise, the embryo is to produce many clones of the embryo. Each embryo is then into a different host mother, who will carry the embryo until she gives birth. The offspring produced are all genetically to each other, however they share no genetic information with the surrogate mother

Adult cell cloning

This involves using only egg cells, and NO SPERM CELL, to produce an embryo. Firstly, the nucleus from an egg cell is removed A nucleus from an adult cell with a chromosome number is inserted into this egg cell. This ensures that the egg cell has the correct number of chromosomes as it will not combine with a sperm cell to achieve this number, which in humans is . A small shock is applied to the modified egg cell. This causes the egg cell to to form an embryo Once the embryo has divided to form a ball of cells, it is inserted into a mother, where it will continue to develop until birth. It is important to note that the embryo contains the genetic material of the cell nucleus, and hence it is genetically identical to it.