Animal groups differ in the mechanisms by which heartbeats are initiated. Most arthropods have a _______ heart while vertebrates have a _______ heart.
A. neurogenic, myogenic
B. myogenic, neurogenic
C. neurogenic, cardiogenic
D. cardiogenic, myogenic
E. autonomous, neurally controlled
A. neurogenic, myogenic
You might also like to view...
During the inflammatory response, which cells release histamine?
a. T cells b. mast cells c. macrophages d. neutrophils e. eosinophils
There is a range of color in mice from black to brown to gray to white. In a region of white sand there is a black volcanic deposit. The white mice survive better on the white sand and the black mice survive better on the black volcanic deposit. This could be an example of
A. sexual selection. B. disruptive selection. C. directional selection. D. stabilizing selection.
Analyses of species-area relationships for many groups of organisms have revealed that values of z in the equation S = cAz tend to be close to __________.
A) 0.03 B) 0.3 C) 3 D) 30
Why have legumes been planted as a cover crop to improve the soil fertility of a field?
A) Legumes have nitrogen-fixing bacteria in their root nodules. B) The leaves of legumes absorb more nitrogen than other plants. C) Legumes have carbon-fixing bacteria in their root nodules. D) Legumes aid organic decomposition. E) Legumes need about 100 times less nitrogen than other plants.