For starters, humans have feelings and cells. If we get hurt we can feel things such as pain unlike a tent. If you hit a tent there is nothing it feels because it has no feelings. We have cells all through our body and rocks don't. They are made of other stuff but not cells.
The portal vein directs blood from the GI tract to the liver. The liver is the first organ to receive nutrients that are absorbed from the GI tract. It is the ‘gatekeeper’ and is responsible for filtering out possible toxins before they reach delicate tissues such as the brain.
Answer:
B) A difference in pressure across a distance.
Answer – D. RNA
Like proteins, Ribonucleic acid is another kind of organic molecule that also acts as a catalyst for chemical reactions. Asides acting a catalyst for chemical reactions, proteins have a wide variety of functions that they perform in in living cells.
