What is the cardiac cycle?
A) The movement of blood from the heart to the lungs and then back to the heart
B) The movement of blood from systemic to pulmonary circulation
C) The passage of electrical impulses from the AV node to the SN node to heart muscle
D) The alternating relaxation and contraction of the heart chambers
D
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Which of the following is most likely to fossilize?
A. a crayfish that died in its muddy burrow by a creek B. a jellyfish that died and sunk to the bottom of the ocean C. a lizard that died in the leaf litter on the forest floor D. a leaf that fell from a tree and landed on the surface of a pond E. a snail that died on a rock
The release of excess nitrogen into the environment when certain complex organic substrates are used to make new microbial biomass is called ________.
A. mineralization B. denitrification C. nitrification D. dissimilation
Two species of closely related squirrels both
feed on acorns produced by oak trees. One species feed exclusively near the top of the tree and the other feeds exclusively towards the bottom of the tree. This is an example of
a. competitive exclusion. b. resource partitioning. c. mutualism. d. commensalism. e. mimicry.
Circulation developed due to which of the following?
a. Animals got larger. b. Segmentation allows increasing specialization of body parts. c. The development of a complete digestive tract allows the specialization of regions to carry out a variety of functions. d. Circulatory systems allow more efficient transfer of materials and gave an advantage to the animals that developed them. e. None of these are true.