Blood is carried from the heart to all parts of your body in vessels called

Which of the following best describes homeostasis? a. keeping the internal environment in a stable state b. keeping the external environment in a stable state c. beneficial characteristics resulting from mutation d. reproduction that results in offspring identical to the parent.

Natural selection changes allele frequencies because some survive and reproduce more successfully than others.

The united states uses which source of energy to produce almost 40 percent of its electricity