7. Challenge yourself: You have already learned that mutation is one source of variation in a population. Based on what you have just seen,
what is a second source of variation?

answer; i believe that the correct answer is(d) nondisjunction during meiosis;

cellular respiration oxidizes food into energy in the form of atps.

glycolysis (6 c hexose) > 2x atps are used > 6c hexose biphosphate > 2 x 3c triphosphate >

2 x 3c pyruvate (2x nadh produced from nad) and (4x atp produced)

pyruvate actively pumped mitochondrial matrix.

geologic time scale (for gradpoint) =)