They ensure they leave the system and they also ensure that people get the nutrients they need.
Answer:Bats are not blind and can in fact see quite well using their eyes. While most bats do have advanced ears that give them a form of vision in the dark known as echolocation, these good ears does not require them to have bad eye
Explanation:
BB=Brown as both are big B's
Bb=Brown as there is a big B
bb=Blue as both are little b's
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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