2.10.10 Temperature Regulation

Question 1

The skin is our largest what?

Answer 1

Sense organ

Question 2

It contains many different receptors that enable us to detect what?

Answer 2

Various external stimuli, including touch, pressure, pain, heat and cold

Question 3

Structures within the skin also play an important role in what?

Answer 3

Regulating body temperature (an example of homeostasis)

Question 4

Human skin contains structures involved in processes that can increase or reduce what?

Answer 4

Heat loss to the surroundings

Question 5

Heat exchange (both during warming and cooling) occurs where?

Answer 5

At the body’s surface as this is where the blood comes into closest proximity to the environment

Question 6

One way to increase heat loss is to what?

Answer 6

Supply the capillaries in the skin with a greater volume of blood, which then loses heat to the environment via radiation

Question 7

Arterioles (small vessels that connect arteries to capillaries) have muscles in their walls that can what?

Answer 7

Relax or contract to allow more or less blood to flow through them

Question 8

During vasodilation, these muscles relax, causing what?

Answer 8

Arterioles near the skin to dilate and allowing more blood to flow through capillaries
This is why pale-skinned people go red when they are hot

Question 9

Sweat is secreted by what?

Answer 9

Sweat glands

Question 10

This cools the skin by evaporation which uses What?

Answer 10

Heat energy from the body to convert liquid water into water vapour

Question 11

The hair erector muscles in the skin relax, causing hairs to what?

Answer 11

Lie flat

Question 12

This stops them from forming an insulating layer by trapping air and what?

Answer 12

Allows air to circulate over skin and heat to leave by radiation

Question 13

One way to decrease heat loss is to supply the capillaries in the skin with a smaller volume of blood, minimising what?

Answer 13

The loss of heat to the environment via radiation

Question 14

During vasoconstriction, the muscles in the arteriole walls contract, causing what?

Answer 14

The arterioles near the skin to constrict and allowing less blood to flow through capillaries

Question 15

Vasoconstriction is not, strictly speaking, a ‘warming’ mechanism as it does not raise the temperature of the blood but instead does what?

Answer 15

Reduces heat loss from the blood as it flows through the skin

Question 16

Shivering is a reflex action in response to what?

Answer 16

A decrease in core body temperature

Question 17

Muscles contract in what manner?

Answer 17

Rapid and regular manner

Question 18

The metabolic reactions required to power this shivering generate sufficient heat to what?

Answer 18

Warm the blood and raise the core body temperature

Question 19

The hair erector muscles in the skin contract, causing what?

Answer 19

Hairs to stand on end

Question 20

This forms an insulating layer over the skin’s surface by what?

Answer 20

Trapping air between the hairs and stops heat from being lost by radiation

Question 21

The core body temperature of humans is kept close to what?

Answer 21

37°C

Question 22

A change in core body temperature of more than what, can be fatal?

Answer 22

2°C

Question 23

he human body must be able to make a what, to any rise or fall in body temperature?

Answer 23

Coordinated response

Question 24

Temperature receptors (also known as thermoreceptors) in the skin and hypothalamus (a part of the brain) can detect minute changes in what?

Answer 24

Body temperature

Question 25

The brain then coordinates what, depending on what is required?

Answer 25

cooling or heating response,