Not to be too picky, but the question ought to say a positively charge ion rather than atom.
I will assume that is what you mean. An ion, using ordinary means, will be positive if it loses electrons (which are negative).
An ion can never gain protons. Left alone, the nucleus will remain unchanged for the rest of eternity. D is wrong.
C is wrong. If electrons are gained, the ion will go negative.
B is wrong for the same reason D is. An ion can't gain protons and it can't lose them.
A is the answer.
Answer is A
Firstly axon must reach the threshold level and then depolarisation occurs. Depolarisation phrase means sodium enters and potassium leaves the axon . Choice C can't be because main idea is the entering of sodium ions.
Yes, it’s main function is to protect the organisms from germs, bacteria etc... and cover the essential organs from these organisms too.
Answer:
b. hibernation to lower metabolism in the winter
Explanation:
Tundra, besides the one I live in apparently, are very, very dry because of the cold. This means that it may be helpful to hibernate for the part of the year where it is even too cold for plants and other animals.
