it separates the inside of the cell from the environment outside and it controls substances moving in and out of the cell (selectively permeable)
The answer is none of the above
Answer:
for 16 it is heart.
Explanation:
for 17 it is kidney to bladder
Answer:
not significant to the overall mass of the atom
Explanation:
The mass number of an atom is the combination of the mass of the protons and neutrons. Electrons are not included because their mass are so insignificant that is doesn't change the total mass much, therefore they are left out. The mass of an electron is about 1,830 times smaller than protons and neutrons.
