Oxygen and nutrients from the mother's blood are transferred across the placenta to the fetus through the umbilical cord. This enriched blood flows through the umbilical vein toward the baby's liver. There it moves through a shunt called the ductus venosus. This allows some of the blood to go to the liver.
A small amount of the blood continues on to the lungs. Most of this blood is shunted through the ductus arteriosus to the descending aorta. This blood then enters the umbilical arteries and flows into the placenta. The oxygen rich blood then returns to the fetus via the third vessel in the umbilical cord (umbilical vein). The oxygen rich blood that enters the fetus passes through the fetal liver and enters the right side of the heart.
The law of segregation is the Mendel’s laws or principles explain that traits are passed from parents to offspring individually instead of as pairs, groups or sets.This is a law or principle which states that during the formation of gametes, two copies of each heredity factors separate out so that the new offspring can get one factor of both the parents. This law was the first law in this direction.
Meiosis is characterized by one round of DNA replication followed by two rounds of cell division, resulting in haploid germ cells. Crossing-over of DNA results in genetic exchange of genes between maternal and paternal DNA.