Answer:
D
Explanation:
It is often like this: cell->tissue->organ->system
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
Answer:
excretory system and circulatory system
Explanation:
Blood is part of circulatory system and as it move through various organs it exchanges the gases i.e give oxygen to the cell and take carbon dioxide from them. After taking CO2, the blood becomes impure and hence it passes through the kidney before going to the heart. Kidney is part of excretory system which removes carbon dioxide from blood and thus purifies it.
Answer: plasma
Explanation:
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