How are twins born?
You may have come across twins. Have you ever wondered how two babies are born at the same time? Normally a woman delivers only one child at a time. This child can either be a male or a female. Sometimes, however, two or more children are born at a time. Two children born of the same mother at one time are known as twins. Do you know how twins are born?
Between the 10th and the 18th day from the onset of menstruation, the reproductive organs of the female produce an egg called ovum. If during this period the female mates with a male, one of the male sperms fuses with the ovum. This union of the ovum and sperm is known as fertilization and the female is said to have become pregnant. 280 days later, the woman gives birth to a child.
But sometimes after the conception, the ovum divides itself into two parts. Both these parts develop in the womb separately as two embryos. As a result, two babies are born simultaneously. The two children so produced are similar in complexion and appearance. Most of their traits are similar. Both the children will always be either boy is girls. This is because they are produced from the same ovum. Such twins are called identical twins.
Sometimes the twins may not be similar. They could also belong to different sex. How is that possible? This is possible when two sperms form the male semen enter separately into two ova of the same female. The two ova then develop into two different babies. The children so produced may be different from one another. They may or may not be from the same sex. Their characteristics may also differ. Such twins are called non-identical or fraternal twins.
Sometimes we come cross the term Siamese twins. The term Siamese for conjoined twin is derived form the famous celebrated twins, change and Eng-Bunker born in
Mekong, Siam (now ) in 1811. They were joined
by a cartilaginous band at the chest. Both of them died with in a gap of three
hours at the age of 62 in 1874. However, such twins are very rare. Thailand