Duchenne muyscular dystrophy is caused by a mutation on the X chromosome, so a male gets it from his mother's X, if she is a carrier. The male child gets a Y and no X from his father, so the disease is always transmitted through the X from the mother. If a female gets Duchenne muscular dystrophy she has to have two X chromosomes, one from a carrier mother and another from from an affected father. This is virtually impossible because most males die before childbearing age and there is no way a female child can get an X from a man who does not live long enough to procreate. About eight percent of carrier women do show some muscle weakness, but they do not have the disease.
The nucleolus is the central support structure
False , as with deer , a buck has antlers , and a doe has no antlers
Answer:
If I am correct it is when the weaker individuals or mutated individuals are killed of by other predators or by nature. Because they cannot survive this is natural selection because they are killed of by nature. Then if they are weak their species will go extinct, thus they are naturally selected to die and only the strong species remain.
Trait
I'm sorry I don't know how to explain it.
