Answer:
For early earth, it was filled with loads of oxygen and could kill humans if they breathed the oxygen that was in the air about 100 million years ago. This massive amount of oxygen cause massive creatures like the dinosaurs to exist. Current earth has an atmosphere with not too much oxygen.
Explanation:
brainliest
Answer:
The correct answer is C. be more likely to have cancer at some point in his/her life.
Explanation:
Cell cycle checkpoints are controlled by different proteins which are coded by different genes. They are important in cell cycle regulation and stops cell cycle immediately if they find any problem in the cell like mutation.
The cell cycle will not be continued if the problem does not solve and cell death will occur which prevents cancer by preventing the mutation to spread into new cells.
Therefore if a mutation occurs in certain genes that enforce a checkpoint on the cell cycle then the mutated gene will pass in new cells and the mutated cells will grow uncontrollably due to no checkpoints so the person will probably have cancer at some point in his or her life.
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:
A. As a young naturalist, Charles Darwin traveled around the world and made many discoveries on a small British navy ship, HMS Beagle.
