Use the Following Information When Answering the Corresponding Question(s)

question 14

Multiple Choice

Use the following information when answering the corresponding question(s) .
Lymph hearts are pumping structures that drive lymph through the lymphatic system,returning it to the circulatory system at the large veins entering the heart.Researchers examined rate and strength of pumping of lymph hearts in two species of amphibians,a toad (Bufo marinus) and a frog (Rana catesbiana) .During hemorrhage or dehydration,the volume of blood in the circulatory system falls.A hormone,arginine vasotocin (AVT) ,is released in these situations.The researchers examined the effect of AVT on lymph heart function.They found that AVT increased pressure at the lymph heart but did not affect the rate of lymph heart pumping.They also examined the effect of atrial natriuretic peptide (ANP) ,a hormone that is released when blood volume is higher than normal.(E.A.DeGrauw and S.S.Hillman.2004.General function and endocrine control of the posterior lymph hearts in Bufo marinus and Rana catesbiana.Physiological and Biochemical Zoology 77(4) :594-600. )
-Refer to the paragraph on lymph hearts.If atrial natriuretic peptide (ANP) has an effect on the lymph hearts,what effect would logically be predicted?

• A)Lymph heart rate would increase.
• B)Lymph heart rate would decrease.
• C)Lymph heart pressure would increase.
• D)Lymph heart pressure would decrease.

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Definitions:

Political Power

The ability or capacity to influence or control the behavior of people or the course of events, often exercised by government officials or entities.

Pig Breeding

The practice of selectively mating pigs to improve desirable traits such as size, growth rate, and meat quality.

Infrastructure

In anthropological theory, the economic foundation of a society, including its subsistence practices and the tools and other material equipment used to make a living.

Superstructure

In Marxist theory, the social, political, and ideological systems and institutions that derive from and support the economic base of a society.