Mid-ocean ridges, which contribute to the process of sea-floor spreading, form as a result of .

A. earthquake activity that causes subduction

B. a rift valley, like the Red Sea, being filled

C. older ocean floor that moves toward the ridge

D. volcanic activity that produces magma

In natural selection, what is actually “selected? ” a) alleles are directly selected b) genotypes are directly selected c) phenotypes are directly selected d) entire populations are directly selected

What do isotopes of uranium have the same number of? what do they have a different number of? a) same number of protons; different number of electrons b) same number of protons; different number of neutrons c) same number of electrons; different number of protons d) same number of neutrons; different number of protons

Which of the following terms best matches this definition: the process where humans choose the traits that will be present in the next generation through breeding. question 4 options: genetic determinism artificial selection acquired selection natural selection