B4: Respiration

Question 1

What is anaerobic respiration?

Answer 1

When energy is released from glucose without oxygen

Question 2

When does anaerobic respiration often happen in humans?

Answer 2

During intense exercise when we cannot take in enough oxygen

Question 3

What is the word equation for anaerobic respiration in humans?

Answer 3

Glucose –> Lactic Acid + Energy

Question 4

The special type of anaerobic respiration carried out by yeast is called…

Answer 4

…..fermentation

Question 5

What is the equation for fermentation?

Answer 5

Glucose –> Ethanol + Carbon Dioxide (+ Energy)

Question 6

What is yeast used for?

Answer 6

Making Beer

Making Wine

Making Bread

Question 7

What is aerobic respiration?

Answer 7

When an organism releases energy from glucose by reacting it with oxygen.

Question 8

List some reasons why humans need energy?

Answer 8

To keep warm

To move

To grow

To keep the body functioning

Question 9

Where does the glucose that humans use in respiration come from?

Answer 9

Food (carbohydrates)

Question 10

What is the word equation for aerobic respiration?

Answer 10

Glucose + Oxygen –> Carbon Dioxide + Water + Energy

Question 11

How do our bodies get the oxygen needed for aerobic respiration?

Answer 11

We breathe in oxygen from the air

Question 12

How are the waste products of aerobic respiration removed from the body?

Answer 12

Carbon dioxide (+ Water) are breathed out

Question 13

Where does aerobic respiration happen?

Answer 13

Within the mitochondria of cells

Question 14

Muscle cells carry out lots of aerobic respiration. Therefore they contain many…

Answer 14

mitochondria

Question 15

How does glucose get into cells.

Answer 15

1. Carbohydrate is eaten
2. Carbohydrate is broken down into glucose in the small intestine.
3. Glucose is absorbed into the blood plasma.4. Glucose exits the blood and enters the body’s cells.

Question 16

How does oxygen get into cells?

Answer 16

1. Oxygen is breathed into lungs and diffuses into the blood in the alveoli
2. Oxygen is carried by red blood cells and diffuses into the cells in blood capillaries

Question 17

What is the function of haemoglobin in red blood cells?

Answer 17

Oxygen sticks to the haemoglobin which allows the red blood cell to carry oxygen around.

Question 18

Use the diagram to complete the sentences below about how oxygen gets into the body (breathing in/ inhalation).

• When you breathe in, the intercostal muscles …………..
• The diaphragm moves ……………………………………
• This increases the ……………………. which decreases the ……………………………
• This causes air to ………………………………………..

Answer 18

• When you breathe in, the intercostal muscles pull the ribs up
• The diaphragm moves down
• This increases the volume of the chest which decreases the pressure
• This causes air to rush into the lungs

Question 19

Smoking can cause a lung disease called emphysema. Describe how this disease makes it difficult to breathe.

Answer 19

The disease destroys alveoli which greatly reduces the surface area of the lungs. This reduces gas exchange meaning less oxgen will be entering the blood.

Question 20

Complete the following sentences to describe how asthma can affect breathing.

• People with asthma have airways that are …………………
• If asthmatic breathe these things in, the muscles around their bronchioles …………………
• This ……………….. the airways
• The lining of the airways becomes …………………
• This narrows the airways further and makes it ……………

Answer 20

• People with asthma have airways that are too sensitive to certain things e.g. pollen
• If asthmatic breathe these things in, the muscles around their bronchioles contract
• This narrows the airways
• The lining of the airways becomes inflamed and fluid builds up
• This narrows the airways further and makes it difficult to breathe