SB9e Cellular respiraqtion

Question 1

What do organisms require a constant supply of energy for?

Answer 1

o Movement.
o Homeostasis and keeping warm.
o Producing and breaking down substances (metabolism).
o Repair.

Question 2

Name the two types of respiration.

Answer 2

Aerobic
Anaerobic

Question 3

What does Aerobic respiration require and where does it take place?

Answer 3

requires oxygen, takes place in the mitochondria.

Question 4

What does Anaerobic respiration require and where does it take place?

Answer 4

no oxygen, takes place in the cytoplasm.

Question 5

State the formula of aerobic respiration

Answer 5

Glucose + Oxygen  Carbon Dioxide + Water

Question 6

What changes occur during exercise and why?

Answer 6

o the heart rate increases.

o the rate and depth of breathing increases.

o the arteries supplying the muscles dilate

 These changes help to provide oxygen and glucose to muscles and
remove carbon dioxide more quickly

Question 7

How does Regular exercise strengthen the heart?

Answer 7

o the heart to become bigger.

o the amount of blood pumped by the heart to increase.

o the walls of the heart to become thicker and stronger.

Question 8

Why does the resting pulse rate get slower as a person becomes fitter?

Answer 8

This happens because their heart is stronger therefore has a more efficient pump which means that it requires a less amount of beats to pump blood round the body

Question 9

When is Anaerobic respiration useful?

Answer 9

Anaerobic respiration is useful when a burst of energy is needed
without oxygen being available

Question 9

When does anaerobic respiration occur and give me its formula.

Answer 9

If oxygen is used up faster than it is supplied, the cells start carrying out
anaerobic respiration, which produces lactic acid.

Glucose -> Lactic Acid

Question 10

Why is this important in the animal kingdom?

Answer 10

This is important for animals that may need to move fast, such as when
sprinting to get away from a predator

Question 11

What effect does anaerobic respiration have

Answer 11

o Causes muscles to tire more easily because there is less energy.

o Produces lactic acid that can cause pain (for example, lactic acid build up in the heart occurs when coronary arteries are blocked and can lead to cell death).

o Decreases the pH inside cells (this can lead to enzymes denaturing).

Question 12

What does EPOC stand for?

Answer 12

Excess post-exercise oxygen consumption

Question 13

What is the preposE of EPOC?

Answer 13

o replace the oxygen lost from blood and muscles.
o and to oxidise lactic acid so that it can be removed.

Question 14

What is anaerobic respiration in yeast called?

Answer 14

fermentation

Question 15

What is the formula for fermentation?

Answer 15

Glucose  Ethanol + Carbon Dioxide

Question 16

What are the uses for the products of fermentation?

Answer 16

 The ethanol can be used for brewing and the
CO2 can be used for bread and cheese
making

Question 17

State the Core practical for respiration rates

Answer 17

 Organisms respire, producing CO2 and water.

 The soda lime absorbs the CO2.

 This creates a drop in pressure so the coloured liquid in the capillary tube moves towards the chamber.

 The distance moved by the liquid in a fixed time can be used to calculate the rate of respiration

Question 18

State the necessary controls for the core practical respiration rates experiment and how they affect the result.

Answer 18

o Temperature– temperature affects the rate of enzymatic reactions. Respiration is a series of enzymatic reactions so temperature needs to be maintained. This can be done with a water bath.

o Soda lime (or KOH) – to absorb CO2.

o Glass beads (sometimes) – to have the same mass on the other side of the respirometer