TWITWINSNS

Identical Identical andandnon-non-identicalidentical

• Non identicalNon identical identical

, , and Identical twins form when one egg and Identical twins form when one egg has been fertilised by one sperm and the has been fertilised by one sperm and the

zygote splits into two. This happens at the zygote splits into two. This happens at the very earliest stage of development, when very earliest stage of development, when the zygote is no more than a cluster of a the zygote is no more than a cluster of a

few cells. Dividing this early in conception few cells. Dividing this early in conception means that each baby has exactly the means that each baby has exactly the same genetic information as the other.same genetic information as the other.

Identical twins can also occur when one a Identical twins can also occur when one a woman has undergone fertility assistance woman has undergone fertility assistance and has had one fertilised egg returned to and has had one fertilised egg returned to

her uterus. her uterus.

IDENTICALIDENTICALTWINSTWINS

• If this egg then splits into two, an If this egg then splits into two, an identical twin pregnancy can result.identical twin pregnancy can result.

• Identical twins are not dependent on Identical twins are not dependent on race, country or ethnicity. The odds race, country or ethnicity. The odds of having identical twins are the of having identical twins are the same for every couple, in every same for every couple, in every pregnancy, wherever they live in the pregnancy, wherever they live in the world.world.

• Around one in every three sets of Around one in every three sets of twins born is identical, and the twins born is identical, and the remaining 2/3 is of the non-identical remaining 2/3 is of the non-identical varietyvariety..

NON-IDENTICAL NON-IDENTICAL

TIWNSTIWNS• Non-identical twins are uniquely Non-identical twins are uniquely

separate individuals who just happen separate individuals who just happen to be gestating at the same time and to be gestating at the same time and place as each other. Non-identical place as each other. Non-identical twins form from two completely twins form from two completely separate eggs which are fertilised by separate eggs which are fertilised by two completely separate sperm. These two completely separate sperm. These fraternal twins are no more alike than fraternal twins are no more alike than any other siblings in a family with the any other siblings in a family with the same biological mother and father.same biological mother and father.

•Some people still believe that the Some people still believe that the incidence of having twins skips a incidence of having twins skips a generation but this is not true.generation but this is not true.

•Because identical twins share the Because identical twins share the same genes, they are always the same genes, they are always the same gender. But non-identical same gender. But non-identical twins may be the same gender or twins may be the same gender or the opposite because they only the opposite because they only share 50% of the same genetic share 50% of the same genetic coding.coding.

Sometimes, twins have Sometimes, twins have problems, for example problems, for example some times they born some times they born

togethertogether

jokjokeeThat funny moment when you That funny moment when you

see two twins arguing and see two twins arguing and one says to the otherone says to the other

- - uglyugly

Ja ja ja ja ja ja Ja ja ja ja ja ja ja jaja ja

AND THIS IS OUR AND THIS IS OUR PRESENTATIONPRESENTATION

FOR NOWFOR NOW