Introduction to Cloning

Cloning is the process of creating an exact replica of an organism. As you can see, no part of that definition mentions technology. In a sense, identical twins are clones! There are two ways that humans can utilize to create clones: artificial embryo twinning and somatic cell nuclear transfer (SCNT).
Artificial embryo twinning is relatively low-tech, mimicking natural twinning. In natural twinning, a zygote divides into two separate cells that are far enough apart to develop into two individuals. In artificial embryo twinning, a zygote is allowed to split into two cells, which are then manually separated to develop independently. The embryos are implanted in surrogate mothers and allowed to mature. The downside of this method of cloning is that an existing individual cannot be cloned. Let’s say you want a clone of yourself. Too bad. But if you want a clone for your child-to-be, who is just a few cells big, the cells can be utilized to make a twin. If the embryo is a complex structure with specialized cells, it cannot be cloned.
Somatic cell nuclear transfer is a more technological approach to cloning. A somatic cell is any cell other than a gamete. To clone using SCNT, an egg cell is devoid of genetic material. A somatic cell is then fused with the egg using electric pulses. This way, the new zygote will have genetic material from the donor of the somatic cell only. The zygote is allowed to grow a little before being implanted in a surrogate mother. Even though the process is complex and the survival rate of the clone is low, it has the advantage of producing clones of an existing organism. If you ever want a clone, this is how you would get it.
Unfortunately, your clone probably will not survive to do your homework for you, or will turn out to be defective. Dolly the sheep was created after 277 eggs, 29 of which yielded embryos, and only three of which survived to birth. Dolly was the only one to survive to adulthood, and even then died an early death, probably from a defect caused by the electric pulses used to fuse the somatic cell and egg.