System Simulation

Question 1 of 4

Activity 39.2 Quiz

In this simulation, which mechanism is used to regulate body temperature?

Genetic regulation

Positive feedback

Negative feedback

Feedforward control

Correct. See Key Concept 39.2 Physiological Systems Function to Maintain Homeostasis of the Internal Environment

Incorrect. See Key Concept 39.2 Physiological Systems Function to Maintain Homeostasis of the Internal Environment

Activity 39.2 Quiz

In the system described by the graph on the Introduction page of the simulation, what is the hypothalamus’s set point for triggering increases in metabolic rate, and what is the hypothalamus’s set point for triggering evaporative heat loss?

36.5 °C; 37.5 °C

35.0 °C; 39.0 °C

36.0 °C; 38.0 °C

Both are 37.0 °C

Correct. See Key Concept 39.2 Physiological Systems Function to Maintain Homeostasis of the Internal Environment

Incorrect. See Key Concept 39.2 Physiological Systems Function to Maintain Homeostasis of the Internal Environment

Activity 39.2 Quiz

Some horses have a condition known as anhidrosis, which leaves them unable to produce sweat. Which part of the graph on the Introduction page of the simulation would be affected by this condition, and why would this be a concern for the owners of these horses?

Metabolic rate would be affected. It is a concern because these horses cannot raise their metabolic rate when their body temperature drops below 36 °C.

Metabolic rate would be affected. It is a concern because these horses cannot lower their metabolic rate when their body temperature increases above 38 °C.

Evaporative heat loss would be affected. It is a concern because these horses cannot decrease their evaporative heat loss when their body temperature drops below 36 °C.

Evaporative heat loss would be affected. It is a concern because these horses cannot increase their evaporative heat loss when their body temperature increases above 38 °C.

Correct. See Key Concept 39.2 Physiological Systems Function to Maintain Homeostasis of the Internal Environment

Incorrect. See Key Concept 39.2 Physiological Systems Function to Maintain Homeostasis of the Internal Environment

Activity 39.2 Quiz

Refer to the graph below generated using the cold setting on the simulation. It represents the response of a human body to a change in temperature.

Mammals that hibernate can drop their set point to temperatures close to freezing. How would this graph differ for such a mammal as it enters a state of hibernation in early winter?

Once triggered, the hibernating mammal’s metabolic response would be much higher than that shown on the graph.

The graph would show that the hibernating mammal’s evaporative heat loss is triggered instead of its metabolic response.

The temperature would continue to drop far below that shown on the graph before the metabolic response is triggered.

The graph would show no change in either metabolic response or evaporative heat loss, no matter how low the temperature dropped.

Correct. See Key Concept 39.2 Physiological Systems Function to Maintain Homeostasis of the Internal Environment

Incorrect. See Key Concept 39.2 Physiological Systems Function to Maintain Homeostasis of the Internal Environment

Chapter 39. System Simulation