Temperature Regulation

Question 1

What is homeostasis?

Answer 1

Maintaining the bodies internal environment to be constant whilst external environmental conditions change. Constant refers to small fluctuations/ stable.

Question 2

What is negative feedback?

Answer 2

When conditions change away from the ideal, to cause a response to reverse the change back to the normal.

Question 3

What is the difference between homeostasis and negative feedback?

Answer 3

Homeostasis is the outcome. Negative feedback is the mechanism that allows homeostasis to be achieved.

Question 4

Describe the basic mechanism of negative feedback?

Answer 4

Change 》Detection by receptors》 Response by effectors 》 Conditions back to norm.

Question 5

What is the average body temp in humans?

Answer 5

37 °C

Question 6

Methods for heat generation?

Answer 6

Muscle contraction
Release of chemicals- thyroxin
Respiration
Metabolism 
Piloerection
Vasoconstriction

Question 7

Methods for heat loss?

Answer 7

Sweating
Vasodilation
Behavioural

Question 8

What is an endotherm?

Answer 8

An organism that can use internal sources of heat, such as heat generation from metabolism in the liver, to maintain its body temperature.

Question 9

What is a Ectotherm?

Answer 9

An organism that relies on external sources of heat, e.g.the sun; to regulate its body temperature.

Question 10

How active are Endotherms?

Answer 10

Endotherms can maintain high activity levels during day and night.

Question 11

How active are Ectotherms?

Answer 11

Activity levels severly reduced when it’s cold. May be completely inactive in winter.

Question 12

Energy requirements of Endotherms?

Answer 12

More enegy needed for metabolism

Question 13

Energy requirements of Ectotherms?

Answer 13

Less energy needed for metabolism

Question 14

Food requirments of Endotherms?

Answer 14

High food requirements to meet energy demands. Eat regularly.
More food is used for maintaining temperature, less is available for growth.

Question 15

Food requirments of Ectotherms?

Answer 15

Less food needed in total so can survive long periods without eating.
More food used for growth.

Question 16

Habitat of Endotherms?

Answer 16

Wide range of habitats including places that are very cold.

Question 17

Habitat of Ectotherm?

Answer 17

Restricted to tropical or temperate regions a on land but can be found throughout all oceans.

Question 18

What are the receptors found in the skin that detect temperature changes in skin surface temperature?

Answer 18

Peripheral temperature receptors

Question 19

What muscles cause you to shiver?

Answer 19

Skeletal Muscles

Question 20

What is piloerection?

Answer 20

Hairs stand up on skin surface. Create insulating layer to retain body heat.

Question 21

What receptors detects change in blood temperature?

Answer 21

Receptors in Hypothalamus

Question 22

What is vasoconstriction?

Answer 22

Where blood vessels near the surface of the skin constrict , moving away from the skin surface. Causing lower amounts of heat to be radiated.

Question 23

What makes vasoconstriction happen?

Answer 23

1. Smooth muscle consricts the arteriole to the capillaries.
2. Shunt vessel dilated due to arteriole relaxing.

Question 24

What is vasodilation?

Answer 24

Where blood vessels near the surface of the skin dilate causing more blood to flow near the skin surface. More heat is radiated/lost.

Question 25

What causes vasoldilation?

Answer 25

1. Arteriole to capillaries dilated.

2. Arteriole to shunt vessel constricted forcing blood into capillaries near skin surface.

Question 26

How does sweating reduce body temperature?

Answer 26

Sweating results in water on the skin’s surface to evapourate. Evaporation uses lots of heat energy so heat is lost.

Question 27

How does burrowing help regulate temperature?

Answer 27

1. Deserts are cold at night. Ground retains heat from day.
2. During hot day send is cooler from night.
3. Less air convection in tunnel can increase heat.

Question 28

How do locusts regulate body temperature?

Answer 28

While body facing Sun to increase surface area. Gain of heat. If too hot, only head faces Sun.
Spiracles increase air flow and evaporation.

Question 29

How do bees regulate heat?

Answer 29

1. Flapping wings creates increased convection. Hear loss.

2. Heat gain by muscle contraction of wings.

Question 30

How do lizards basking in the sun help with temperature regulation?

Answer 30

1. Conduction of heat from ground/rock to lizard. Raising body off ground lowers conduction.
2. Frills increase surface area. More hest absorbed from Sun.