Nitrogen fixation is the process where atmospheric nitrogen is converted by bacteria into biologically usable forms.
plant can not take nitrogen directly from the leaves.
Answer:
Blood plasma:
55% composition of blood contains blood plasma. The plasma contains various proteins and coagulating factors. This mainly include the fluid portion of the blood. Plasma is a straw colored liquid that contains antibodies as well as serum.
Formed elements:
45% composition of blood contains formed element. The formed elements contain RBCs, WBCs and platelets. This mainly include the cells portion of the blood. Formed elements is red color or no color depending on the pigment present in the cells of formed element.
Answer: B. Comparative embryology
Explanation: Good luck! :D
The answer to this question would be: B<span>. It relaxes blood vessels in Harvey’s penis, allowing them to expand.
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Viagra active component is sildenafil citrate which has the ability to relax the smooth muscle in the artery and dilate the arteries of the penis. As the arteries in penis dilate, the blood flow into penis will be increased. This will make penis filled with blood and give pressure to nearby veins causing them to close. All this event cause increased pressure in penis that was making the erection
