Which of the following is a difference between food chains and food webs? food webs contain both plants and animals, but food chains contain only plants. food webs separate organisms by trophic level, but food chains do not. food chains show energy flow in an ecosystem, and food webs do not. food chains are linear, while food webs are complex.

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.