Scientists trying to determine evolutionary relationships among organisms sometimes search for clues by examining how each organism develops from a fertilized egg cell. what name is given to the scientific study of how organisms develop from a single cell into independent living creatures?
a) cytology
b) embryology
c) phylogeny
d) zoology

(amoeba sisters video recap: pedigrees and need

Reactants undergo chemical reaction to form products. this chemical equation represents one such reaction. the coefficient for one of the reactants or products is incorrect. which part of the chemical equation is incorrect?

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.