Hello how are you feeling today I miss your birthday so much I love it hell we
<span>The mother must be present is not a characteristic of imprinting. Since </span>imprinting is not only effective for females only.
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.
The statement that is true of Oparin and Haldane's theory is : the primitive organic molecules were formed in an oxidizing atmosphere in the primordial soup
This is one of the theory that determined how life on earth developed. It was one of the most influental theory on the matter
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