What do pulmonary vein and the inferior vena cava have in common

Which taxon group is more specific, in regards to organisms that are in that group? mammalia animalia

Which best example best demonstrates the importance of having knowledge of evolutionary relationships? a. illustration of a plant b. organ transplantation between species c. blood donation from a human d. do you need sequence of an insect.

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.