What is it called when protein carriers are used with diffusion to move things across the cell membrane?

What is usually (but not always) related to the metabolic processes of living organisms in its organic form?

1. in a certain species of plant, the color purple (p) is dominant to the color white (p). according the punnett square, what is the probability of and offspring being white? 50%25%0%100% 2. in a certain species of plant, the color purple (p) is dominant to the color white (p). according the punnett square, what is the probability of and offspring being white? 0%100%50%25%(picture 1 is for question 1, and picture 2 is for question 2)

Which of the following statements is true about the relationship between genetic variation and natural selection? a. genetic variation must be present in a population before natural selection can act on it. b. genetic variation arises in a population as a result of natural selection. c. natural selection can act on a population whether there is genetic variation within the population or not. d. after natural selection acts on a population, the amount of genetic variation in the population always increases.