Directions: For each DNA sequence given, determine the mRNA and tRNA strands. DNA strand: G G A A T C T C G
mRNA codons:
tRNA anti-codons:

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.