Respiration And Exercise

Front 1

What are the reactions that are involved in respiration catalysed by?

Back 1

Enzymes.

Front 2

What is respiration?

Back 2

Respiration is the process of releasing energy from glucose and occurs in every cell in our bodies. NOT BREATHING!

Front 3

In which other type of organism does respiration occur?

Back 3

Plants

Front 4

What is aerobic respiration?

Back 4

Respiration using oxygen. It's the most efficient way to release energy from glucose.

It happens all the time in plants and animals.

Most of the reactions in aerobic respiration happen inside mitochondria.

Front 5

What is the word equation for respiration?

Back 5

Glucose + oxygen -----> carbon dioxide + water

+ energy

Front 6

State four examples of what the energy released by aerobic respiration is used for.

Back 6

1) To build up larger molecules from smaller ones (like proteins from amino acids).
2) (In animals) to allow the muscles to contract - allowing them to move.
3) In mammals and birds, the energy is used to keep their body temperature constant.

4) In plants, energy from respiration is used to build sugars, nitrates and other nutrients into amino acids, which are then built up into proteins.

Front 7

What do muscle cells use to release energy from glucose?

Back 7

Oxygen

Front 8

Finish the sentence:
An increase in muscle activity requires...

Back 8

...more glucose and oxygen to be supplied to the muscle cells.

For this to happen, blood has to flow at a faster rate.

Front 9

What needs to be removed from muscle cells during periods of exercise?

Back 9

Excess carbon dioxide. For this to happen, blood has to flow at a faster rate.

Front 10

What does physical activity do to the body?

Back 10

1) Increases your breathing rate and makes you breathe more deeply to meet the demand for extra oxygen.

2) Increases the speed at which the heart pumps. (To allow blood to flow to the respiring cells to deliver oxygen and glucose and remove excess carbon dioxide and other toxins).

Front 11

What is glycogen?

Back 11

The animal equivalent of starch in plants. Some glucose from food is stored as glycogen (mainly in the liver but each muscle also has its own store).

Front 12

What is glycogen used for?

Back 12

During vigorous exercise, muscles use glucose rapidly, so some of the stored glycogen is converted back to glucose to provide more energy.

Front 13

When is anaerobic respiration used?

Back 13

When you do vigorous exercise and insufficient oxygen reaches the muscles, anaerobic respiration is used to obtain energy.

Front 14

What is anaerobic respiration?

Back 14

"Anaerobic" means 'without oxygen'; it's the incomplete breakdown of glucose, which produces lactic acid. It occurs in the cytoplasm of the cell.

Front 15

What's the word equation for anaerobic respiration?

Back 15

Glucose ----> energy + lactic acid

Front 16

Why is anaerobic respiration NOT the best way to convert glucose into energy?

Back 16

1) During anaerobic respiration, lactic acid builds up in the muscles, which gets painful. It also causes muscle fatigue - the muscles get tired and they stop contracting efficiently.
2) It does not release as much energy as aerobic respiration.

Front 17

What is one advantage of using anaerobic respiration?

Back 17

You can keep using your muscles for longer (instead of them running out of energy and you ending up being unable to move).

Front 18

What does anaerobic respiration lead to?

Back 18

An 'oxygen debt'.

Front 19

What is an 'oxygen debt'?

Back 19

After vigorous exercise, you breathe hard for a while after you've stopped. This is to 'repay' the oxygen that couldn't be transferred to your muscles in time - your heart, lungs and blood couldn't keep up with the demand during exercise.

Front 20

What is the purpose of the 'oxygen debt'?

Back 20

After exercising anaerobically, lactic acid will have built up in your muscles. It is toxic, so must be removed. You breathe heavily to get more oxygen into your blood, which flows through your muscles to remove the lactic acid by oxidising it to harmless carbon dioxide and water.

Front 21

Complete the sentence:
While high levels of carbon dioxide and lactic acid are detected in the blood (by the brain)...

Back 21

...the pulse and breathing rate stay high to try and rectify the situation.

Lactic acid is removed when blood flows through the muscle. The heart beats harder to increase blood flow and deeper breaths are taken to increase oxygen levels in the blood. Oxygen is what breaks down lactic acid.

Front 22

Where in the mitochondria does respiration occur?

Back 22

In the folds of the inner membrane (the 'cristi').

Front 23

Compare aerobic and anaerobic respiration.

Back 23

1) Aerobic respiration occurs in the mitochondria of the cell, anaerobic respiration occurs in the cytoplasm.

2) Oxygen is needed for aerobic respiration and is not needed for anaerobic respiration.

3) Glucose is completely broken down in aerobic respiration and is not fully broken down in anaerobic respiration.

4) More energy is released through aerobic respiration.

Front 24

How could respiration be compared to photosynthesis?

Back 24

The equations are the mirror image of each other: the products of respiration are the same as the reactants in photosynthesis and vice verse.

Respiration occurs at all times in animals, but does not occur at night (in darkness) in plants.