Non-identical twins are called fraternal twins. They develop from two separate eggs fertilized by two different sperm. Unlike identical twins, fraternal twins share about 50% of their genetic material.
There are at least three ways to produce twins. One is when the female produces two eggs, both of which are fertilized by the male. This is how fraternal twins are produced. Fraternal twins can be both the same sex or different sexes. Fraternal twins may only bear a slight resemblance to one another, no more than any two siblings might. (Fraternal twins can actually have different biological fathers, because the eggs may be produced a day or two apart.) Another is for the woman to produce one egg which is fertilized by the male, and then the egg divides into two. This is the traditional way that so-called identical twins are produced. Identical twins are always the same sex. (I use the term 'so-called,' because they are actually 'mirror image' twins.) A third way is for the woman to produce one egg, which then divides into two, which are both subsequently fertilized. There is a greater chance that such twins will resemble one another than fraternal twins, and they may be the same or opposite sexes.
fraternal twins have two different chromosomes
Sperm contains either an X(female) chromosome or a Y(male) chromosome, whereas the egg contains only an X(female) chromosome. Neither the egg nor the sperm can be said to have a"sex." The combination of an X-bearing sperm with the (X-bearing) egg produces a female baby. The combination of a Y-bearing sperm with the (X-bearing) egg produces a male baby. It might seem that the man (sperm) that determines the sex of the baby, but this assumes that the egg is passive, accepting the first sperm to arrive at the egg. Some recent evidence indicates that this is not so. See the Wikipedia article on "Maternal influence on sex determination.
MZ (monozygotic) twin pairs are identical twins who develop from a single fertilized egg that splits into two embryos. DZ (dizygotic) twin pairs are fraternal twins who develop from two separate eggs fertilized by two different sperm cells. MZ twins share 100% of their DNA while DZ twins share around 50% of their DNA, like any siblings.
There is no such thing as paternal or maternal twins. the only type of twins there are is FRAternal, and Identical. Identical twins are the result of one sperm fertilizing one egg and that fertilized embryo splitting apart and forming two fetuses, therefore the children are born identical, and thus must be of the same sex. Fraternal twins are the result of two eggs being fertilized at the same time by two different sperm, and the children will be born different from the other. As a result, they can be male/male, female/female, and female/male. also there is a very slim chance that fraternal twins can have two different fathers, as it can take up to two weeks after having sex for a sperm to fertilize an egg. so if a female has sex with multiple partners, there is a very small chance that the two twins could be from two fathers.
There are two way twins are formed. Twins can form by two eggs being released by the female and the sperm will fertilize both eggs. The other way twins can be formed is if one fertilized egg divides and forms two eggs.
Non-identical twins are called fraternal twins. They develop from two separate eggs fertilized by two different sperm. Unlike identical twins, fraternal twins share about 50% of their genetic material.
Yes. Conjoined twins are always identical (monozygotic) twins, and identical twins are always the same sex.There is a theoretical case where identical twins could be opposite genders, when the babies are female but in one of the females, a branch of one X chromosome breaks away; however, I don't believe this has ever been observed.
If those eggs are both impregnated by spermatozoa, then she could end up being pregnant with fraternal twins. (Non-identical).
A female boar is called a sow. Sows are known for their maternal instincts and can give birth to litters of piglets.
There are at least three ways to produce twins. One is when the female produces two eggs, both of which are fertilized by the male. This is how fraternal twins are produced. Fraternal twins can be both the same sex or different sexes. Fraternal twins may only bear a slight resemblance to one another, no more than any two siblings might. (Fraternal twins can actually have different biological fathers, because the eggs may be produced a day or two apart.) Another is for the woman to produce one egg which is fertilized by the male, and then the egg divides into two. This is the traditional way that so-called identical twins are produced. Identical twins are always the same sex. (I use the term 'so-called,' because they are actually 'mirror image' twins.) A third way is for the woman to produce one egg, which then divides into two, which are both subsequently fertilized. There is a greater chance that such twins will resemble one another than fraternal twins, and they may be the same or opposite sexes.
First part of my answer is that wattles are a genetic characteristic. They are not normal. Cute, painless, etc., but most goats don't have them. Second part is the easy one. They aren't identical twins. They're fraternal.
boy, girl and simese twins Siamese twins are now properly called conjoined twins. You can have identical twins[ same sex] , fraternal twins [ one male , one female ]. triplets, same way, quadruplets, quintuplists , sextuplets and so on , with fertility drugs.
parent trap???
Sexual prorogation of plants (reproduction) is when a seed is produced inside the flower by using pollen (from the stamen) and a pistil (female part). Asexual prorogation is when a plant uses vegetative parts to produce more plants. There are many different way this happens.
No. In order for them to be identical they needed to start off as the same cell and divide so at first their DNA is identical meaning they have the same sex. During development slight changes may occur but the sex always stays the same. Boy-girl twins are always two different cells meaning that they are not identical. The term for boy-girl twins is furturnal. You can however have boy-boy twins and girl-girl twins that are not identical and they are also called furternal. So basically, identical twins start off as one cell that divides and furternal are two individual cells. There is polar body twinning, that's when the egg splits before fertilization, and that can cause a male and a female. This is called semi identical twins or half twins. They share 75% of their genetic markers.