In a human, how many chromosomes are present in a cell before it undergoes mitosis and meiosis?

What causes eclipses? check all that apply. earth's rotation on its axis moon's shadow covering the sun earth's shadow covering the moon earth's orbit and moon's orbit occasionally aligning the moon and sun's gravity pulling in the same direction

24. how are vaccines used to keep people healthy?

All other things being equal the size of a population will decrease if