The ultimate factor affecting primary productivity is ____.
A. the organic matter in all the organisms of the ecosystem
B. the availability of water
C. the rate of photosynthesis
D. the availability of ATP
E. the amount of inorganic mineral ions in the soil
Answer: C
You might also like to view...
A land developer and several ecologists are discussing how a parcel of private land should be developed while saving twenty hectares as natural habitat
The land developer suggests that the twenty hectares be divided into twenty separate one-hectare areas. The ecologists suggest that it would be better to have one intact parcel of twenty hectares. What is the significance of these different arrangements of the twenty hectares? A) There really is no difference; they should both work equally well. B) The isolated hectare plots increase the ability of individuals to disperse from one habitat to another. C) The isolated plots are more vulnerable to edge effects. D) The large plot will create more inbreeding in many species.
Although each of the following has a better chance of influencing gene frequencies in small populations than in large populations, which one most consistently requires a small population as a precondition for its occurrence?
A) mutation B) nonrandom mating C) genetic drift D) natural selection E) gene flow
Which is not true of RNA?
A. It is usually single-stranded. B. It functions in the cytoplasm. C. It contains both uracil and thymine. D. It contains ribose.
Transfusion reactions are the result of antibody reaction to
A) glycolipids and glycoproteins on the surface of red blood cells. B) MHC molecules on red blood cells. C) MHC molecules on white blood cells. D) plasma proteins. E) foreign antibodies.