Ch 24: Metabolic rate & temperature regulation

The higher the relative humidity: a. The higher the rate of radiation b. The lower the rate of conduction c. The higher

the rate of convection d. The lower the rate of thermoregulation e. The lower the rate of evaporation

e. the lower rate of evaporation

This is a mechanism of heat transfer that involves direct contact: a. conduction b. convection c. radiation d. evaporation e. metabolic rate

a. conduction

3. ___ The loss of heat in the form of infrared waves is termed this: a. radiation b. convection c. conduction d. evaporation

a. radiation

Which of the choices below is not a mechanism of heat production and conservation? a. vasoconstriction of cutaneous blood vessels b. shivering c. sweating d. enhanced thyroxine release

c. sweating

Heat-loss mechanisms do not include this: a. physical activity b. the evaporation of sweat c. behavior measures such as wearing light, loose clothing d. vasodilation of peripheral blood vessels

a. physical activity

The amount of the this substance that is released is probably the most important hormonal factor in determining BMR: a. norepinephrine b. thyroxine c. prolactin d. ADH

b. thyroxine

Many factors influence BMR. What is the most critical factor? a. the way an individual metabolizes fat b. the way skeletal muscles break down glycogen c. the ratio of surface area to volume (weight) of the body d. an individual's body weight

c. the ratio of surface area to volume (weight) of the body

The primary reason elderly people should decrease their caloric intake is that: a. muscle mass and metabolism decline with age b. their appetite begins to diminish c. they have a higher metabolic rate and do not need large amounts of food d. they spend most of the day at rest, and their food will quickly turn to fat

a. muscle mass and metabolism decline with age

When a person's hypothalamic thermostat is set to a higher level and the actual body temperature is below that level, the person may do this: a. pant b. exhibit vasodilation of skin vessels c. perspire heavily d. shiver

d. shiver

T OR F

BMR stands for basal metabolic rate.

T

T OR F

A fever results when the hypothalamic thermostat of the body is reset.

T

T OR F

Thyroxine,a hormone from the thyroid gland regulates a person's resting BMR and ATP production.

T

t or f

Increased body temperature excites neurons and decreases the activity of many enzymes

F

t or f

Heat exhaustion is usually associated with vigorous physical activity, dehydration, and low blood pressure

T

t or f

As the body temperature decreases in hypothermia, shivering stops at about 32 ̊C and cardiac arrest occurs at about 21 ̊C.

T

T or F

During heat stroke, the skin becomes hot and dry and body temperature spirals upward.

T

t OR f

"Cryogens" tend to raise body temperature and "pyrogens" tend to lower body temperature

F

Basal metabolic rate can be measured directly with a (calorimeter, respirometer).

calorimeter

The preoptic center in the (cerebellum, hypothalamus) is the main integrating center for thermoregulation.

hypothalamus

Sources of nutrients and chemical energy come from a general nutritional source called (fuel, food).

food

This category of substances that contain chemical energy, captured long ago, that humans use for heat and conversion to

other types of energy is commonly called (fuel, food).

fuel

Normal body temperature is ______ ̊C and ______ ̊F

37 C

98.6 F

The release of ________________, a hormone, from the ______________ gland increases metabolic rate and is a heat

promoting mechanism.

thyroxine

thyroid

Animals insure that they obtain their nutrients in the proper form and proper concentration by eating, directly or indirectly, the flesh of _____________ or ________________

animals or plants

Chemical energy that powers life on Earth originates from this type of energy - ___________

light

28. The daily energy requirement needed to power the life of the average adult male is about _______Calories.

2500

Todays modern farmers and ranchers support over twice the number of humans that the Earth could normally support

without modern technology and these energy sources - ________ ________

fossil fuels

Today, modern farming and ranching allows over 90% of humans to live and work in ______________ rather than to live

on farms producing food

cities

his byproduct of fossil fuel usage is leading to climate change and ocean acidification - ________

_________

carbon dioxide

____________________ is the name of the energy conversion process found in green ___________ that

intitially produce the chemical energy that is transferred among, and shared by, other living things.

photosynthesis; plants