Birds, unlike mammals, do not have separate exits for urine and feces. Both waste products are eliminated simultaneously through the cloaca. While mammals excrete nitrogenous wastes mostly in the form of urea, birds convert it to uric acid or guanine, which reduces water loss in comparison.
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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F1 generation are allowed to self-pollinate..
Humans have characteristics that differentiate them from other organisms. One of them is the ability to talk properly. This is due to the presence of larynx in the lower part of the throat causing humans to talk. Another characteristic is the ability to reason out and think properly and also humans can best work his or her imagination. Another characteristic is having an upright posture to maintain balance as one stands or walks. Lastly is the ability to blush which is a unique characteristic only for humans.