Which of the following is TRUE about retinal detachment?

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.

Which of the following determines the specificity of a dna probe? a. type of radiation b. level of enzymatic activity c. number of neutrons d. complementary base pairing

How do demetri's results show that digestive enzymes are crucial to maintaining homeostasis inside the body?