How are fraternal twins formed ?

How are identical twins formed in human being ?

How many eggs and sperms are required to produce fraternal twins ?

Identical twins are

Chemical twins are

How many ova are released in the case of maternal twins and fraternal twins respectively in human ?

How many ova are released in the case of maternal twins and fraternal twins respectively in human ?

Siamese twins are always either male or female and never be male and female. a. Why are the twins called Siamese twins? b. What do you mean by identical twins? c. What are fraternal twins?

One child is haemophilic (sex-linked trait), while its fraternal twins brother is normal. Which one of the following informations is most appropriate?

At the time of ovulation usually a single ovum is released. However, how many ova are released in case of identical twins and fraternal. Twins respectively?