At complex III in the mitochondria, electrons are passed to to shuttle, or pass, the electrons to complex IV.

children tend to take more after their grandparents more than their parents. it’s the dna you received that was passed down to you somewhere in your family. maybe one of your grandparents had/has straight hair and you might have gotten it from them.

genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).

answer: substrate concentration. enzymes work best when there is a high enough substrate concentration for the reaction they catalyse.