No, they don't have organs and organ system.
Cells form tissues, Tissues form organs, Organs forms organ system; Unicellular have their own one cell only. So, it can't possible that they have organs or organ system.
It would be merging cells.
The correct answer is meat and cheese
Proteins are mostly found in abundance in animal products. Eggs are also a great source of them which is why animal products should be consumed as proteins are necessary for the functioning of the body.
Answer:
I think Indirect contact with animal feces
hope it helped :)
Answer:
Catastrophism, gradualism, and uniformitarianism I believe!