Question 1

The major thermoregulatory center ("thermostat") in mammals is located within the central nervous system in the _______ and uses _______ as feedback information.

Accepted Answer

The major thermoregulatory center ("thermostat") in mammals is located in the hypothalamus of the central nervous system and uses feedback information from the hypothalamic temperature to regulate body temperature.

Question 2

Refer to the graphs showing the results of an experiment in which researchers heated and cooled the hypothalamus of a mammal and determined its metabolic rates at different environmental (ambient) temperatures.  Based on the figure, which statement is true?

Accepted Answer

The answer of Refer to the graphs showing the results...

Question 3

The linings of hollow organs consist of _______ tissue.

Accepted Answer

The answer of The linings of hollow organs consist of...

Question 4

Which statement about thermoregulatory set points is true?

Accepted Answer

Changes in skin temperature can signal the hypothalamus to adjust the metabolic set point, which affects thermoregulation throughout the body. The set points for different thermoregulatory processes can vary depending on a variety of factors, including external temperature, time of day, and individual physiological conditions. Therefore, choice A is incorrect. Similarly, the set points for thermoregulatory processes can differ between individuals of the same species, and even within an individual over time. Therefore, choice B and C are also incorrect. Finally, while changes in skin temperature can affect the hypothalamus, the temperature of the hypothalamus itself does not serve as a positive feedback signal. Therefore, choice E is incorrect.

Question 5

Refer to the graphs showing the results of an experiment in which researchers heated and cooled the hypothalamus of a mammal and determined its metabolic rates at different environmental (ambient) temperatures.  In this experiment, the hypothalamic temperature provides

Accepted Answer

The answer of Refer to the graphs showing the results...

Question 6

Which is most likely to occur if a baby bat's hypothalamus is experimentally cooled using an implanted probe?

Accepted Answer

Cooling the hypothalamus would likely trigger mechanisms to increase body temperature, such as nonshivering thermogenesis in brown fat, to counteract the perceived drop in temperature.

Question 7

A single-celled paramecium is limited in the size it can become because its volume grows faster than its _______, and exchanges with the environment are limited by the surface area of its cell membrane.

Accepted Answer

The answer of A single-celled paramecium is limited in the...

Question 8

The four major types of tissues are epithelial, muscle, nervous, and _______.

Accepted Answer

The answer of The four major types of tissues are...

Question 9

To calculate the sensitivity of a physiological process or reaction to temperature, you must calculate its rate both at a certain temperature and at a temperature that is lower by _______°C.

Accepted Answer

The answer of To calculate the sensitivity of a physiological...

Question 10

Which statement about thermoregulation is true?

Accepted Answer

Aspirin works by inhibiting the production of prostaglandins, which can cause fever. By reducing the number of prostaglandins, aspirin can lower the hypothalamic set point and return the body temperature to normal.

Note: A is false because the thermoregulatory set point is lowest during sleep. B is false because entrance into hibernation begins with a decrease in metabolic rate. D is false because hyperthermia is an elevated body temperature, not caused by starvation. E is false because cooling the hypothalamus typically increases metabolic rate by causing shivering and increasing heat production.

Question 11

_______ feedback amplifies a response or increases deviation from a set point.

Accepted Answer

The answer of _______ feedback amplifies a response or increases...

Question 12

Sea urchins attach to rocks and use specialized mouth structures to feed.They have an evolutionary advantage over unicellular planktonic protozoa floating by in that they can more effectively _______ on other organisms and resist the forces of waves.

Accepted Answer

The answer of Sea urchins attach to rocks and use...

Question 13

Which statement about hibernation in a ground squirrel is true?

Accepted Answer

Hibernation in a ground squirrel involves a significant decrease in metabolic rate, often to only a fraction of the basal metabolic rate. This reduction in metabolism allows the animal to conserve energy during the winter months. Additionally, during hibernation, the body temperature of the squirrel can fluctuate depending on the animal's needs, with brief periods of regulated hyperthermia occurring to bring the animal back to a "normal" temperature before settling back into a lower temperature state.

Question 14

The hypothalamus serves in part as an integrated thermoregulatory center defining an organism's response to changes in its thermal environment.Because the hypothalamus normally serves to produce metabolic responses that reverse the direction of environmental temperature change, the control it exerts is termed

Accepted Answer

The control exerted by the hypothalamus is termed negative feedback, as it produces metabolic responses that reverse the direction of environmental temperature change.

Question 15

Which statement about brown fat is true?

Accepted Answer

Brown fat allows metabolic fuels to be consumed to produce heat, which is its primary function.

Answer: D 
 Brown fat uses thermogenin to produce heat instead of ATP like other types of cells.

Answer: E 
 Brown fat is primarily found in infants, although recent research has shown that it may also be present in small amounts in adult humans.

Question 16

The maintenance of stable physiological conditions in the internal environment of an organism is called _______.

Accepted Answer

The answer of The maintenance of stable physiological conditions in...

Question 17

Which of the following would be stimulated by a rise in a mammal's hypothalamic temperature?

Accepted Answer

A rise in the hypothalamic temperature would lead to the body trying to dissipate excess heat, which includes mechanisms such as dilation of blood vessels in the skin to increase heat loss.

Question 18

In dissecting a mysterious structure, you find that it has a lumen lined by an epithelium surrounded by connective tissue and smooth muscle.You conclude the structure is a(n) _______ (cell, tissue, organ, or organ system) from an animal.

Accepted Answer

The answer of In dissecting a mysterious structure, you find...

Question 19

One of the responses of the human immune system to an infection is a raised body temperature, or fever.The adaptive value of the fever is that a raised body temperature

Accepted Answer

A raised body temperature, or fever, helps fight pathogenic microbes by creating an environment that is less favorable for their growth and replication. This is accomplished by increasing the metabolic rate of the body's cells and activating immune responses that help to eliminate the infection.

Question 20

If a woman has about 3 liters of blood plasma, then she will have about _______ liters of interstitial fluid, the fluid that bathes all her cells.

Accepted Answer

The answer of If a woman has about 3 liters...

Quiz 39: Physiology, Homeostasis, and Temperature Regulation

The major thermoregulatory center ("thermostat") in mammals is located within the central nervous system in the _ and uses _ as feedback information.

Refer to the graphs showing the results of an experiment in which researchers heated and cooled the hypothalamus of a mammal and determined its metabolic rates at different environmental (ambient) temperatures. Based on the figure, which statement is true?