Respiration and Gas Exchange

Question 1

What is respiration (definition)?

Answer 1

The process of transferring energy from glucose, which happens constantly in every cell

Question 2

What is the word equation for aerobic respiration?

Answer 2

Glucose + Oxygen -> Carbon Dioxide + Water (+ATP)

Question 3

What is the symbol equation for aerobic respiration?

Answer 3

C6H12O6 + 6O2 -> 6CO2 + 6H2O (+ATP)

Question 4

How much ATP does aerobic respiration produce?

ATP = Adenosine Triphosphate (energy molecule)

Answer 4

32 molecules per molecule of glucose

Question 5

When does anaerobic respiration occur?

Answer 5

When the body doesn’t have access to enough oxygen. i.e. vigorous exercise

Question 6

How many molecules of ATP does anaerobic respiration produce?

Answer 6

Only 2 molecules per molecule of glucose

Question 7

What is the word equation for anaerobic respiration in animals?

Answer 7

Glucose -> Lactic acid (+ATP)

Question 8

What is the word equation for anaerobic respiration in plants and fungi?

Answer 8

Glucose -> Carbon Dioxide + Ethanol (+ATP)

Question 9

What is the indicator that detects CO2 and what colour does it change in the presence of CO2?

Answer 9

Hydrogen Carbonate indicator

Orange -> Yellow

Question 10

Describe an experiment to show that beans produce CO2

Answer 10

1. Soak dried beans in water so that they germinate (therefore will respire)
2. Boil a similar mass of beans, which will kill them (they can’t respire). This will be the control
3. Put same amount of HC indicator and place a gauze platform in the tube, placing beans on it
4. Seal the test tube with a rubber bung and leave for a period of time

Question 11

How are leaves adapted for efficient gas exchange?

Answer 11

1. Large SA for diffusion
2. Thin so gases travel short distances to reach cells
3. Air space inside the leaf allows gases to move easily through the leaf
4. Lower surface made of stomata which allows gases to diffuse in and out

Question 12

What colour does hydrogen-carbonate indicator go in normal CO2 levels?

Answer 12

Orange

Question 13

What colour does hydrogen-carbonate indicator go in high CO2 levels?

Answer 13

Yellow

Question 14

What colour does hydrogen-carbonate indicator go in low CO2 levels?

Answer 14

Purple

Question 15

Describe what happens when the body breathes in

Answer 15

Intercostal muscles and diaphragm contract

Lungs move up and out

Thorax volume increases and pressure decreases, drawing air in

Question 16

Describe what happens when the body breathes out

Answer 16

Intercostal muscles and diaphragm relax

Lungs move in and down

Thorax volume decreases and pressure increases, pushing air out

Question 17

How are alveoli adapted for efficient gas exchange?

Answer 17

1. Huge number of alveoli = extremely LSA
2. Moist lining for gases to dissolve in
3. One cell thick walls means small distance for gases to dissolve through
4. Great blood supply = high concentration gradient
5. Walls are permeable

Question 18

How does tobacco cause problems in the body?

Answer 18

1. Causes emphysema by reducing the SA of the alveoli
2. The tar damages the cilia and prevents them from keeping the trachea clear
3. Tar irritates the bronchi, encouraging an overproduction of mucus
4. Carbon monoxide is produced
5. Tobacco smoke contains carcinogens