Deck 11: Homeostasis

Question 1

Why was Max Gilpin's coach, Stinson, charged with reckless homicide?

A) He held football practice during an excessively hot and humid day, which may have caused Max Gilpin's death.
B) By requiring excessive exertion for a large person on a hot humid day, he may have caused Max Gilpin to dehydrate, overheat, and die.
C) He held a particularly strenuous football practice which may have caused Max Gilpin's death.
D) Because he did not know Max Gilpin was taking Adderall, he caused his death by allowing him to play football.

Answer 1

B

Question 2

If you are in good health, your body temperature will

A) Be a constant 98.6°F
B) Range between about 98 and 100°F
C) Range between about 98 and 99°F
D) Be a constant 37°C
E) Range between 35 and 40°C

Answer 2

C

Question 3

Homeostasis is

A) The ability to produce heat and maintain an internal temperature
B) The ability to maintain an absolutely constant internal body state
C) The varying of the body state within a narrow range
D) The ability to maintain the internal body state within a narrow range
E) The constant state of the body

Answer 3

D

Question 4

Why is the body temperature maintained at about 37°C?

A) That's the easiest to maintain given the average temperatures in our habitat.
B) That's how much heat our metabolic processes can produce.
C) That's the temperature at which our metabolic processes are most efficient.
D) That's the average body temperature of all animals.
E) That's the temperature that kills most pathogens.

Question 5

If a human body has the capacity to regulate its processes and maintain homeostasis, why does the body sometimes get out of balance?

A) Disease, illness, or extreme circumstances can overwhelm the body's ability to regulate.
B) Usually, errors in genetic coding end up being the cause.
C) Drugs like Adderall or alcohol disrupt the control mechanisms.
D) Some people are just better at regulation than others.
E) This is an active area of research now because the answer is not known.

Question 6

Homeostasis is maintained by negative feedback using a controller, effectors, and sensors. The heating/cooling system in your home also works by negative feedback. Which part in that system is the controller?

A) The heat pump/air conditioner
B) The thermostat
C) The insulation
D) The heating/cooling vents
E) The ceiling fans

Question 7

Homeostasis is maintained by negative feedback using a controller, effectors, and sensors. The heating/cooling system in your home also works by negative feedback. Which part in that system is the effector?

A) The heat pump/air conditioner
B) The thermostat
C) The insulation
D) The heating/cooling vents
E) The ceiling fans

Question 8

In your body's heating and cooling system, which of the following would be a positive effector?

A) Shivering
B) Sweating
C) Taking off a jacket
D) Moving to the shade
E) Drinking

Question 9

What do the effectors do in the process of maintaining homeostasis?

A) They measure whatever property is being regulated.
B) They send signals to the appropriate sensors.
C) They send signals to the appropriate controllers.
D) They change the value of the system according to how the controller directs them.
E) They always increase the value of the system.

Question 10

What does the sensor do in the process of maintaining homeostasis?

A) They measure what is being regulated.
B) They send signals to the appropriate sensors.
C) They send signals to the appropriate controllers.
D) They change the value of the system according to how the controller directs them.
E) They always increase the value of the system.

Question 11

How does the body monitor its core temperature?

A) Nerve cells in the skin feed the information to the hypothalamus.
B) Nerve cells monitor the temperature of the hypothalamus.
C) The pituitary gland in the brain tracks the temperature of the blood.
D) Core blood temperature alters the speed of nerve cells in the hypothalamus.
E) Core blood temperature alters the speed of the chemical reactions in the pituitary gland.

Question 12

Where is the hypothalamus located in the body?

A) In the brain connected to the pituitary gland
B) Near the heart
C) In association with the thyroid
D) At the body's core
E) In the spinal column

Question 13

Since the body monitors core temperature constantly, why also monitor the skin temperature?

A) A back-up system in case the core temperature system fails due to illness
B) The skin temperature sensors are more accurate.
C) You can have many more skin sensors.
D) So the body knows the external body temperature
E) So the body can anticipate and minimize core temperature changes

Question 14

Why does it make sense that the sensors and controller of body temperature reside in the brain?

A) Because the brain works best at the correct temperature
B) Because the brain enables the body's response to temperature changes
C) Because deep inside the brain is considered the body's core
D) Because temperature changes affect the brain first
E) Because temperature changes happen most quickly in the brain

Question 15

What controls the core body temperature?

A) The brain
B) The pituitary gland
C) The skin sensors
D) The brain stem
E) The hypothalamus

Question 16

Why does it makes sense that metabolism is measured in calories?

A) If your metabolism is slow you tend to gain weight, so it makes sense to tie it to caloric intake.
B) The chemical reactions of metabolism produce heat energy, and energy is measured in Calories.
C) If you are very active you burn a lot of Calories, so it makes sense to measure metabolism that way.
D) The more Calories you consume, the higher your metabolism will be.
E) Metabolic rate is determined by calorie consumption.

Question 17

What is metabolism?

A) The mechanism that provides energy to the body
B) The mechanism that allows you to maintain your body temperature
C) A measure of the number of chemical reactions occurring in the body
D) The collective chemical reactions of all your cells keeping you alive
E) The number of calories you need to maintain your body processes

Question 18

What is the basic energy you need to maintain your body processes when you are at rest?

A) Your metabolic rate
B) Your basic caloric intake
C) Your basal metabolic rate
D) Your baseline metabolic rate
E) Your average metabolic rate

Question 19

Why does your body often have excess heat to get rid of?

A) The basal metabolic rate at rest produces excess heat.
B) Any activity that raises the metabolic rate above basal produces excess heat.
C) Because our bodies are well insulated, they can easily overheat.
D) We live in relatively warm climates.
E) Because we are mammals, and mammals are "warm blooded."

Question 20

Because our bodies are generally warmer than the environment, one way we lose heat without effort on our part is by

A) Going outside
B) Evaporation from our skin and lungs
C) Convection from our skin and lungs
D) Radiation from our skin and lungs
E) Conduction from out skin and lungs

Question 21

How can blood circulation cool you off?

A) Blood warms up in areas of high metabolic activity and warm blood is directed toward external surfaces where heat can be transferred to the cooler environment.
B) Blood warmed up at the surface of the skin loses heat as it travels in toward the core of the body.
C) Blood circulation can be speeded up by increasing the heart rate in order to dissipate heat more quickly.
D) Blood circulation can be slowed down by slowing down the heart rate, using less energy, thereby reducing heat production.
E) Blood circulation can only serve to warm you up.

Question 22

Why is it more difficult to lose excess body heat on a hot day?

A) Because you gain heat from the outside
B) Because as air temperature gets closer to body temperature, heat loss from the body to the air by evaporation slows
C) Because as air temperature gets closer to body temperature, heat transfer from the warmer body to the cooler air by convection slows
D) Because very hot air causes heat stroke, where the body's mechanisms for losing heat shut down
E) Because blood circulation nearing the skin gets warmer rather than getting cooler

Question 23

Why is it easier to overheat on a humid day?

A) It feels hotter than when the air is drier.
B) Heat convection is slower when the air is humid.
C) Radiative heat loss declines when the air is humid.
D) Evaporative heat loss by sweating decreases when the air is humid.
E) Water is evaporating out of the air instead of off the body.

Question 24

How does a body lose heat through exhalation?

A) The air exhaled is warmed by the body and heat is then lost.
B) Radiative cooling of the exhaled air
C) Evaporative cooling from the moist surface of the lungs
D) Convective cooling from the interior lining of the lungs
E) The motion of the air out of the body cools it.

Question 25

How does shivering warm the body?

A) Areas of skin moving against each other generate heat by friction
B) Shivering increases blood flow, which distributes heat.
C) It requires the heart rate to increase, which increases heat production which increases body temperature.
D) Increased muscle contraction increases the metabolic rate which increases heat production.
E) Shivering works on mammals that have more fur or hair than humans, but it is no longer an effective heat producer for humans.

Question 26

Why do your nose, ears, fingers and toes get cold first when you are in a cold environment?

A) They're the farthest from the body's heat sources.
B) They stick out the most into the cold environment.
C) These areas can't shiver .
D) There is the least amount of blood circulation in these areas.
E) The body directs blood flow in toward the core of the body to maintain core temperature.

Question 27

You get goose bumps when you're cold. What purpose does that serve?

A) They thicken the skin, improving insulation.
B) Nothing really. It's just a reflex.
C) They puff up fur to trap air that helps retain body heat for mammals that have fur or hair on their skin.
D) They are a shivering mechanism that helps increase metabolic rate to increase heat production.
E) Because blood circulation is directed away from the skin when a body is cold, the skin shrinks a little bit and this shows up as goose bumps.

Question 28

What type of heat loss is prevented by insulation from fur, feathers, or fat?

A) Evaporation
B) Convection
C) Circulation
D) Radiation
E) Metabolism

Question 29

If your body is healthy and the functions maintaining homeostasis are working correctly, how can a person get heat stroke?

A) They're overweight and thus have too large a surface area to allow sufficient heat loss.
B) They're out of shape, so they sweat too much.
C) Conditions are such that the body heats up faster than its cooling effectors can cool it down.
D) They lose too many salts in sweat.
E) The environment may be very dry, leading to excessive evaporation.

Question 30

How does the hypothalamus "know" what the body's temperature is at any given time?

A) Blood temperature sensors in the hypothalamus itself and in skin sensors.
B) It monitors the core temperature near the heart.
C) It does not "know" the actual body temperature, but it senses any increases or decreases and responds accordingly.
D) Skin sensors keep track of internal temperature.
E) In dogs, it's been found to be blood temperature sensors in the brain, but it's not clear what the system is in humans.

Question 31

How does the hypothalamus "know" to raise the body's temperature set point to produce a fever?

A) Infected blood passes over the temperature-sensing nerve cells in the brain, and when those cells fire more slowly, the hypothalamus raises the body's temperature set point.
B) The infecting pathogen interferes with the normal temperature set point, so it changes.
C) In response to an infection, a particular chemical signal binds to the hypothalamus, raising the set point temperature.
D) You shiver.
E) The immune system bypasses the hypothalamus to raise the body's temperature.

Question 32

What does the hypothalamus do to raise the body temperature for a fever?

A) It raises the temperature of the blood flowing over it.
B) It triggers shivering, chills, and sweating.
C) It triggers movement of the body to a warmer place.
D) It enhances radiative cooling.
E) It triggers shivering and chills.

Question 33

How does a fan help cool you off?

A) The moving air minimizes radiative heat gain.
B) Conduction of heat away from the body increases.
C) The moving air increases convection of heat to a cooler environment.
D) The moving air decreases evaporation of sweat.
E) Moving air is sort of the opposite of insulation.

Question 34

Only physiological responses work to heat or cool the body. True or False?

A) True: The hypothalamus has to trigger the appropriate effectors.
B) False: There is "mind over matter" where you can convince yourself you are cooler.
C) True: Voluntary behaviors can help, but they don't cause significant change.
D) False: Voluntary behaviors also have an significant effect on body temperature.
E) False: Physiological responses don't cool or heat the body sufficiently.

Question 35

Why does lettuce wilt if it sits in salad dressing for awhile?

A) The salt in the dressing pulls the water out of the plant.
B) By osmosis, the water flows down the salt gradient from inside the cell to outside.
C) By active transport, the water flows down the salt gradient from inside the cell to outside.
D) It doesn't, because a cell is impermeable to water so the water doesn't move.
E) By diffusion, salt moves into the cells of the plant.

Question 36

Related to cell permeability, what made life on land more difficult than life in the water?

A) In the water, water doesn't tend to move out of permeable cells.
B) Cells are more permeable to water when they are dry outside.
C) On dry land, any water tends to move into permeable cells.
D) Osmosis doesn't tend to occur on dry land.
E) Active transport works more effectively when the cell is wet externally.

Question 37

Which of the following structures is most responsible for controlling water loss, making urine, and maintaining proper salt concentration in the blood?

A) Hypothalamus
B) Liver
C) Kidney
D) Bladder
E) Cell membrane

Question 38

What is the function of the Loop of Henle?

A) Reabsorption of salts by diffusion
B) Filtration of compounds in the blood
C) Secretion of compounds out of the blood
D) Active transport of salt into blood
E) Passage of urine to the bladder

Question 39

How does heat stroke occur?

A) Overheating
B) Dehydrating
C) Overheating and dehydrating
D) Excess salt in the body
E) Excess ADH

Question 40

How does the hypothalamus monitor water in the body?

A) If blood is too concentrated, the hypothalamus registers ADH in the blood.
B) If blood is too concentrated, the hypothalamus nerve cells will contain too much salt.
C) If blood is too concentrated, the hypothalamus it registers dehydration in its own cells.
D) If blood is too concentrated, nerve cells in the hypothalamus it has nerve cells that lose water by osmosis and fire more slowly.
E) If blood is too concentrated, in the hypothalamus it registers that its cells are losing water by osmosis.

Question 41

How does ADH work and what does it do?

A) It binds to water molecules, making them too large to diffuse out of the blood stream, retaining water when the body needs it.
B) It binds to blood cells, making them more porous to water so it more easily diffuses back into them and is not lost in urine filtration.
C) It binds to the kidney tubules, making them less porous to water so less water filters out.
D) It binds to nerve cells in hypothalamus, signaling that the body is dehydrated and should retain water.
E) It binds to the collecting tubules in the kidney, opening pores to allow water to flow back out of the kidney into the blood.

Question 42

When does the hypothalamus signal thirst?

A) When it detects dehydration prior to releasing ADH
B) When it detects continuing dehydration despite releasing ADH
C) When it detects dehydration regardless of whether ADH is present
D) Anytime the body seems to be in danger of overheating
E) Anytime the level of salt in the blood is detected as being too high

Question 43

How is a "hangover" as a result of drinking alcohol related to water balance in the body?

A) Alcohol is a diuretic, and the hangover feeling is a symptom of dehydration.
B) Alcohol behaves like ADH, and the hangover feeling is a symptom of dehydration.
C) Just as alcohol interferes with a body's overall balance system, it interferes with the water balance system, making you feel hungover.
D) Excessive alcohol use prevents sweating, and retaining extra water and potential overheating is part of what makes you feel hungover.
E) Alcohol makes the kidneys more porous such that they are unable to retain water, and feeling hungover is a symptom of dehydration.

Question 44

Why is the hypothalamus important to the basic function of the body?

A) It controls muscle contractions.
B) It controls osmosis.
C) It controls homeostasis.
D) It controls a fever.
E) It controls brain function.
"Scientist Spotlight"

Question 45

What is Dr. Homer William Smith famous for?

A) He figured out how the hypothalamus works to control water balance.
B) He found the cure for kidney disease.
C) He found non-invasive ways to experiment on the hypothalamus.
D) He figured out the details of how kidneys work and applied that knowledge to treating kidney disease.
E) He determined that alcohol acts as a diuretic.

Question 46

How does a dialysis machine work to filter the blood when the kidneys fail?

A) It uses osmosis and diffusion between the blood and a fluid specially formulated to suit the patient to correct their water and salt balance.
B) It pumps the blood through a filter specially designed to suit the patient to correct their water and salt balance.
C) It prevents air bubbles from forming as blood pumped external to the body for "cleaning."
D) It removes metabolic wastes from the blood, but it cannot adjust water.
E) It uses active transport to artificially filter the blood.
"Life Application"

Question 47

From the body's perspective, how is Gatorade different from plain water?

A) It isn't really. It's just marketed better.
B) It's flavored.
C) It is essentially artificial sweat so it replaces not just water lost, but various other trace substances lost in sweat.
D) It makes athletes stronger.
E) It works whether it's warm or cold.

Question 48

How did Dr. H.T. Hammel determine that it was the hypothalamus in dogs which was sensing their temperature?

A) He kept their heads at a different temperature than their bodies and they reacted only according to the temperature of their heads.
B) He kept the hypothalamus at a different temperature than their external environment, and they reacted only according to the temperature of the hypothalamus.
C) The dogs did not react at all to changes to the external environment unless their head temperature was changed, also.
D) The dogs would only pant when their skin temperature was increased.
E) The dogs would not shiver when just the hypothalamus was cooled.

Question 49

What may have caused Max Gilpin to collapse during football practice?

Question 50

All animals maintain a constant body temperature of about 98°F.

Question 51

List one example of something held relatively constant in the body by homeostasis.

Question 52

What process maintains homeostasis in the body?

Question 53

What is the job of the effectors in the negative feedback system that maintains homeostasis in the body?

Question 54

What is the name of the "controller" in the body's negative feedback systems?

Question 55

Where are the two types of temperature sensors in the body's negative feedback system?

Question 56

Your body uses a certain amount of energy when it is at rest, just keeping you alive. What is that called?

Question 57

How does your body generate heat?

Question 58

How does sweating cool the body?

Question 59

Is it more difficult for a mammal to warm up or cool down?

Question 60

Of what use is a fever?

Question 61

In addition to the involuntary physiological responses the body has to control its temperature, what other mechanism does it use?

Question 62

What is the name of the movement of molecules down the gradient?

Question 63

What is a membrane called that lets some molecules across but not others?

Question 64

If energy is required to move a molecule across a membrane, what is that process called?

Question 65

How does the body control water and salt balance over time?

Question 66

What is the main waste product of metabolism?

Question 67

What is the name of the system of tubules that control water balance in the kidney?

Question 68

What are two ways humans lose water?

Question 69

What does ADH do?

Question 70

What is the main way humans gain water?