More than likely mutation
Photosynthesis is important to living organisms because it is the number one source of oxygen in the atmosphere. ... Green plants and trees use photosynthesis to make food from sunlight, carbon dioxide and water in the atmosphere: It is their primary source of energy. Hope this helps
Concentration gradient across the membrane. Proteins in the membrane allow specific molecules through, passively.
The answer is because it lowers the number of chromosomes in half, ensuring that the fusion will have the appropriate amount of chromosomes after the fusing of the sperm and the egg.
