The level of organization is plants, coral and water. Water came first.
Ductus Arteriosus is a blood vessel normally present in fetuses during development. The blood vessel is designed to bypass the pulmonary artery and brings blood to the Descending Aorta, as the fetus cannot breath through the lung (being as they are fluid filled). This is normally not a problem because oxygenated blood comes from the mother's blood supply.
Patent Ductus Arteriosus, is what happens when that vessel does not close. While not as dangerous as other congenital defects. However, because there is still a bypass, blood that normally need to be oxygenated by going through the pulmonary arteries to the lungs, can be diverted and placed into the blood stream without vital oxygen. This condition may eventually lead to CHF (congestive Heart Failure) and Pulmonary Hypertension if not treated.
Answer:
The correct answer is A) Conformation.
Explanation:
Proton pumps are usually molecules that are able to change its conformation in order to transport molecules from one side to the other. The amino acid sequence cannot be changed, because it would change completely the function of the protein. For example, the sodium/potassium pump changes its conformation in order to move these molecules from one side of the membrane to the other.