Which body of water is most likely to be a marine ecosystem? A: River. B: Estuary. C: Lake. D: Pond

Which would be the outcome in a fertilized egg if the process of meiosis did not occur? twice as many chromosomes as the parents half as many chromosomes as the parents same number of chromosomes as the parents triple the number of chromosomes as the parents?

What type of pollution does household garbage cause

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.