Answer:During pregnancy, red blood cells from the unborn baby can cross into the mother's blood through the placenta. If the mother is Rh-negative, her immune system treats Rh-positive fetal cells as if they were a foreign substance. The mother's body makes antibodies against the fetal blood cells
Explanation:The number of protons present in the nucleus of an atom is known as Atomic Number. Atomic Number helps in determining the chemical properties of an atom. Thus it is given that the given ion contains 6 protons thus the atomic number of the ion will be six. hope this helps
<span>The two identical chromosomes that result from DNA replication are referred to assister chromatids. Sister chromatids are held together by proteins at a region of the chromosome called the centromere.</span>