Scientists use a variety of tools to learn about the history of the earth, evolution, environmental change, and its effects. Which type of evidence is most affected by human error (and thus less reliable)? fossils and the fossil record
rock core samples and strata
mathematical and computer models
areas of impact

Building glycogen from glucose molecules is an example of what

How many chromosomes does each human cell contain? a. 23 chromosomes b. 26 chromosomes c. 43 chromosomes d. 46 chromosomes

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.