In mammalian kidneys, blood in the vasa recta and fluid in the loop of Henle flow in opposite directions to create a ________ multiplier system.
A. reversible
B. stepped
C. exponential
D. homeostatic
E. countercurrent
Answer: E
You might also like to view...
You are trying to determine if honeybees have social immunity to nosema, an economically devastating parasite that attacks adult honeybees. You mark some honeybees with a spot of red dye and expose them to a solution containing a sublethal dose of the parasites. Another set of honeybees is exposed to the same solution without parasites. After this exposure, you mix some of the unmarked bees with
the marked bees (Mixed Group). The rest of the unmarked bees are not mixed with other bees (Unmixed Group). When you expose both the Mixed and Unmixed groups of bees to a lethal dose of the parasite, all the bees die. What might you conclude from this experiment? A. The marked honeybees exposed the unmarked bees to a lethal dose of the parasite. B. There is no social immunity for nosema in honeybees. C. There is social immunity, but only at a sublethal dose. D. There is no social immunity, but there is humoral immunity. E. There is both social and nonspecific immunity for nosema in honeybees.
What term describes an exotic species that thrives in a new habitat and quickly threatens the existing environment?
a. a pest species b. a keystone species c. an advanced predator species d. an invasive species
The olfactory receptors discovered by Richard Axel and Linda Buck are members of a large family of similar receptor molecules termed
A. intracellular receptors. B. ligand-gated ion channels. C. voltage-gated ion channels. D. G-protein coupled receptors. E. serine/threonine proteases.
Seventy to 90 percent of the genetic material in a gamete made in your body could be inherited from your mother. How could this be?
a. The above statement is incorrect. Fifty percent of the genetic material in your gametes comes from your father. b. You receive maternal genes through the placenta and through breast milk. c. The X chromosome is substantially larger than the Y chromosome. d. Your maternal genes kill off your paternal genes at a greater rate than your paternal genes kill off your maternal genes. e. You receive many mitochondria, which have their own genome, from your mother, but not from your father.