Twins Baby

Twins are two or more individuals who share the same uterus and usually, but not always, born in the same day. Mother to content carrying twins would thus have a multiple birth and usually contains the shorter (34 to 36 weeks) than a single baby pregnancy. Because preterm birth usually have health consequences for babies, multiple births are often handled specially somewhat different than normal birth.
Labor twins are common in animals because many animals that produce eggs are cooked (ready to be fertilized) at the same time. Domestic animals such as cats, dogs, rats, or sheep usually have more than one child at birth.


Type of twins

Viewed from the origin of the zygote, there are two types of labor twins: fraternal (dizygotic) and identical (monozygotic). Dizygotic twins is common in vertebrates, whereas monozygotic twins is a rare thing. Humans have this ability. Armadillo stripes-nine (Dacypus novemcinctus) if the delivery always have four monozygotic twins.


Dizygotic or fraternal twins (DZ)

Dizygotic twins (known as "non-identical twins") occur because the zygote-zygote formed from different eggs. There are more than one egg is attached to the womb wall by the sperm cells at the same time. In humans, the process of ovulation is sometimes release more than one mature egg into the fallopian tubes if they are fertilized will bring more than one zygote.
Dizygotic twins are genetically no different from ordinary civil and thrive in the amnion and placenta are separated. They may have different sexes or the same.
The study also showed that the DZ twin talents passed on to offspring (genetic), but only female offspring / female who can show (because only a woman / female who can manage expenses eggs).


Monozygotic or identical twins (MZ)

Monozygotic twins occur when a single fertilized egg cell to form one zygote (monozygotic). In its development, the zygote divides into different embryos. The two embryos develop into fetuses sharing the same womb. Depending on the phase separation of zygotes, identical twins may share the same amnion (known as monoamniotic) or different amnion. Furthermore, not a monoamniotic identical twins can share the same placenta (known as monochorionic, monochorionic) or not. All must monochorionic monoamniotic twins. Sharing the same amnion (or amniotic and the same placenta) can cause complications in pregnancy. For example, the umbilical cord of monoamniotic twins can be twisted to reduce or interfere with the distribution of blood to the developing fetus.
MZ twin pairs is always the same and are genetically the same (clones) except when there is a mutation in the development of one individual. Twin similarity level is very high, with differences sometimes occur in the form of similarity of reflection. Differences occur in the details, such as fingerprints. When individuals grow older, the level of similarity is usually reduced because of personal experience or a different lifestyle. Research reveals the existence of epigenetic effects in the process of distinguishing individuals MZ twins, because different genes are activated. Although there is the influence of habit or experience that influenced these differences, scientists considered more random processes play a role in the differences that occur. Studies with rats even showed a difference in histone activity (associated with epigenetic) of the first four cells are formed.
Until now scientists have not agreed on the existence of genetic influences for MZ twin events. But note there are several places in the world that has a frequency of MZ twins is higher than other places