Exercise

Question 1

What does exercise do to the heart rate?

Answer 1

Increases it.

Question 2

Muscle cells combine ______ with _______. This is called ________ and it provides the muscles with ________ to contract.

Answer 2

Glucose with Oxygen. This is called respiration and it provides the muscles with energy to contract.

Question 3

An increase in muscle activity requires more _______ and more _______ to be supplied to the muscle cells.

Answer 3

An increase in muscle activity requires more glucose in more oxygen to be supplied to the muscle cells.

Question 4

Because extra oxygen is added, extra _____-______ needs to be removed

Answer 4

Carbon Dioxide.

Question 5

When more oxygen needs to be supplied to the cells and more carbon-dioxide needs to be removed from the cells, what happens to the blood flow?

Answer 5

Blood must flow at a faster rate to keep up with the demand for oxygen and removal of carbon-dioxide.

Question 6

What happens the depth of your breathing when you exercise?

Answer 6

You need to breathe in more deeply to keep up with the oxygen demand.

Question 7

Some glucose from food is stored as ________

Answer 7

Glycogen.

Question 8

Where is Glycogen mainly stored? And where else can be it stored?

Answer 8

In the liver, but each muscle has a supply of glycogen too.

Question 9

During vigorous exercise, the muscles break down glucose at a _____ rate. What happens to some glycogen during vigorous exercise?

Answer 9

Some glycogen is converted back into glucose and is used as energy.

Question 10

What process ocurrs when there isn’t enough oxygen?

Answer 10

Anaerobic respiration takes place.

Question 11

What does anaerobic mean?

Answer 11

Without oxygen

Question 12

What does anaerobic produce, besides energy?

Answer 12

Lactic acid/

Question 13

Anaerobic respiration is the __________ breakdown of glucose.

Answer 13

Incomplete breakdown

Question 14

Why is anaerobic respiration not the best way to convert energy to glucose? 3 reasons.

Answer 14

• Because a build-up of lactic acid in the muscles is painful.
• It causes muscle fatigue (muscles get tired and stop working efficiently).
• It doesn’t release as much energy as aerobic respiration.

Question 15

What’s an advantage of anaerobic respiration?

Answer 15

It means that you can keep on using your muscles a while longer, useful in emergencies when oxygen is scarce.

Question 16

What does anaerobic respiration lead to?

Answer 16

An oxygen debt.

Question 17

What is an oxygen debt?

Answer 17

You didn’t get enough oxygen when you were exercising before, therefore you have a debt to repay to your heart, lungs and blood because they couldn’t keep up with your demand earlier on.

Question 18

Why do you breathe heavily after vigorously exercising?

Answer 18

Because you’re repaying your oxygen debt by getting more oxygen into your blood.

Question 19

Once you’ve taken in a lot of oxygen after vigorously exercising, what happens to this oxygen?

Answer 19

Blood flows through your muscles and oxidises the lactic acid, thus removing it.

Question 20

What happens to lactic acid when it is oxidised?

Answer 20

It’s converted into harmless carbon-dioxide and water.

Question 21

When your brain detects large amounts of carbon-dioxide and lactic acid in the blood, what does your body do to rectify the situation?

Answer 21

The pulse quickens and the breathing rate quickens.