2, because a theory is not a law that can not be changed, and new evidence can change a theory.
Amino acid reactions. Amino acids via their various chemical functionalities can undergo numerous chemical reactions.
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.
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Enzymes are meant to break down food in the mouth making it easier to consume and the food and gather the nutrients inside
A night person is more active and awake at night whilst a morning person is the opposite.
