You Are Studying a Large Tropical Reptile That Has a High

question 4

Multiple Choice

You are studying a large tropical reptile that has a high and relatively stable body temperature. How would you determine whether this animal is an endotherm or an ectotherm?

• A) You know from its high and stable body temperature that it must be an endotherm.
• B) You know that it is an ectotherm because it is not a bird or mammal.
• C) You subject this reptile to various temperatures in the lab and find that its body temperature and metabolic rate change with the ambient temperature. You conclude that it is an ectotherm.
• D) You note that its environment has a high and stable temperature. Because its body temperature matches the environmental temperature, you conclude that it is an ectotherm.
• E) You measure the metabolic rate of the reptile, and because it is higher than that of a related species that lives in temperate forests, you conclude that this reptile is an endotherm and its relative is an ectotherm.

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Definitions:

Baroreceptor Reflex

Detects changes in blood pressure and produces changes in heart rate, heart force of contraction, and blood vessel diameter that return blood pressure to homeostatic levels.

Sympathetic Output

The activity or signals generated by the sympathetic nervous system, which is involved in the body's fight-or-flight response.

SA Node

The SA node, or sinoatrial node, acts as the heart's natural pacemaker, initiating the electrical impulse that triggers heart contractions and regulates heart rate.

Venous Compliance

The capacity of veins to expand in response to increased blood volume, an important factor in regulating blood pressure.