For each predator-prey system: a. determine which of the variables, x or y, represents the prey population and which represents the predator population b. is the growth of the prey restricted just by the predators or by other factors as well? do the predators feed only on the prey or do they have additional food sources? explain.

Animal bodies (and even plant bodies for that matter) are complex enough that life couldn't exist without enzymes. enzymes are usually large, complex biological catalysts that are expensive to make. enzymes speed up the rate of chemical reactions without being used up during the reaction (they can be reused many times). they are highly specific in the reactions they regulate. knowing what enzymes are and how they function, why does this explain why complex life forms could not exist if there were no enzymes.

Which of the following are the functions of the integumentary system? yadda-yadda, the 1st answer is the brainliest. : )

Define the apical impulse and describe its normal location, size, and duration. which abnormal conditions may affect the location of the apical impulse? explain the mechanism producing normal first and second heart sounds. describe the effect of respiration on the heart sounds. describe the characteristics of the first heart sound and its intensity at the apex of the heart and at the base. describe the characteristics of the second heart sound and its intensity at the apex of the heart and at the base.