Marine teleost fishes deal with the osmotic stress of living in seawater mainly by
a. active transport of ions into the body through the gills.
b. excreting nitrogenous wastes through their kidneys as urea.
c. active transport of ions out of the body by chloride cells.
d. excreting excess salt through the actions of specialized salt glands in their heads.
e. maintaining high levels of urea and trimethylamine oxide in body fluids.
C
You might also like to view...
Which is the correct equation for the Hardy-Weinberg principle?
a. p2 + 2pq2 + q2 + q2 = 100 b. 2p2 + 2pq + 2q2 = 1000 c. p2 + 2p + 2q + q2 = 1 d. p2 ? 2pq + q2 = 1 e. p2 + 2pq + q2 = 1
Species turnover on islands has been observed to be low. What does this suggest about process in the equilibrium model of island biogeography?
A. Facilitation is of minor importance to this model. B. Secondary succession rarely succeeds. C. Succession on most islands is a fairly orderly process. D. The intermediate disturbance hypothesis can explain colonization rates. E. Immigration of new species often can not keep up with extinction.
Compared with sponges, cnidarians have a wider array of cell types permitting more sophisticated tissue functions. These functions include (select all that apply):
A. secretion of digestive enzymes. B. muscle contraction/movement. C. the ability to sense the environment via a network of nerve cells. D. the ability to communicate within the organism using hormones. E. none of these
__________ refers to nutrient enrichment of any ecosystem that is otherwise low in nutrients. Fill in the blank(s) with the appropriate word(s)