Metabolic Rate 2.3

Question 1

What is Metabolic Rate?

Answer 1

The quantity of energy used by the body over a given time. It is measure in kilojoules or kilocalories.

Question 2

What can metabolic rate be measured as?

Answer 2

Oxygen consumption per unit time
Carbon Dioxide produced per unit time
Energy (heat) production per unit time

Question 3

Ways to measure metabolic rate (equiptment)

Answer 3

Respirometers, oxygen probes, carbon dioxide probes and calorimeters.

Question 4

What do Respirometers do?

Answer 4

Measure the oxygen uptake by an organism

Question 5

What do Calorimeters do?

Answer 5

Measure the heat generated by an organism over a period of time

Question 6

What is the Basal Metabolic Rate? BMR

Answer 6

At rest (periods of inactivity) the metabolic rate is known as the BMR. At rest it is low. During rest the body only uses energy to keep vital organs functioning properly.

Question 7

What is the general rule of metabolic rate?

Answer 7

The greater the mass of an organism, the higher the organism’s metabolic rate.

Question 8

Why is BMR higher per unit of body mass?

Answer 8

The higher metabolic rate of small animals need a greater delivery of oxygen to tissues around the body

Question 9

What do high metabolic rates require?

Answer 9

Efficient delivery of oxygen to cells since aerobic respiration must be high to supply sufficient ATP for the cellular processes.

Question 10

What do Arteries do?

Answer 10

Carry blood Away from the heART (under high pressure)

Question 11

What are capillaries and what do they do?

Answer 11

They are the smallest blood vessels which exchange nutrients, gases and waste products between the blood and body tissue

Question 12

What do veins do?

Answer 12

Carry blood into the heart (under low pressure)

Question 13

The heart and its chambers?

Answer 13

The heart has two types of chambers atria (singular atrium) and ventricles.

Question 14

What are Atria

Answer 14

A heart chamber where blood enters.

Question 15

What are ventricles?

Answer 15

Heart chamber where blood leaves the heart

Question 16

What has a closed circulatory system and what is it?

Answer 16

All vertebrates have closed circulatory systems where the blood is contained in a continuous circuit of blood vessels and is kept moving by a muscular pump (the heart)

Question 17

What have single circulatory systems and what is it?

Answer 17

Fish. A heart with two chambers - an atrium and a ventricle. The blood passes through the heart only once.

Question 18

In fish the blood flows to the gills at ____ pressure

Answer 18

High

Question 19

In fish the blood is delivered to the capillaries at ____ pressure

Answer 19

Low

Question 20

Is the blood flow in fish efficient?

Answer 20

No it is primitive and ineffecient

Question 21

What is a double circulatory system?

Answer 21

Blood passes through the heart twice. Blood is pumped to both the lungs and the body both at high pressure.

Question 22

Is double more efficient than single?

Answer 22

yes

Question 23

What has an incomplete double circulatory system and what is it?

Answer 23

Reptiles and Amphibians

There is only one ventricle and some mixing of oxygenated blood from the lungs and deoxygenated blood from the body.

Question 24

Why is mixing not a major problem in Amphibians?

Answer 24

The blood returning from the body has been partially oxygenated through it’s skin.

Question 25

What has a complete double circulatory system and what is this?

Answer 25

Birds and mammals.
4 chambers - 2 Atria and 2 Ventricles
Blood passes through the heart twice during each complete circuit of the body.

Question 26

What does the double circulatory systems in birds and mammals enable?

Answer 26

Higher metabolic rates to be maintained.

Question 27

Is there mixing in birds and mammals blood?

Answer 27

No

Question 28

Why are complete double circulatory systems more efficient

Answer 28

The oxygenated blood can be pumped out at a higher pressure.