B9 - Respiration

Question 1

What is cellular respiration?

Answer 1

Exothermic reaction that occurs continuously in living cells.

Question 2

Aerobic Respiration Equation

Answer 2

Glucose + Oxygen —> Carbon Dioxide + Water

C6H12O6 + 6O2 ——> 6CO2 + 6H2O

Question 3

What is the energy transferred in aerobic respiration used for?

Answer 3

• Supplies all the energy needed for living processes.

Question 4

What is the energy transferred during respiration used for?

Answer 4

• Used to enable muscles to contract.

Question 5

Does the human body respond to the increased demand for energy?

Answer 5

Yes.

Question 6

Body Response to Exercise.

Answer 6

• Increase in heart rate, breathing rate and breath volume. - Glycogen stores in the muscles are converted to glucose for cellular respiration.
• Flow of oxygenated blood to the muscles increases.

Question 7

Why does the body respond like this to exercise?

Answer 7

• To increase the rate of supply of glucose and oxygen to the muscles.
• The rate of removal of carbon dioxide from the muscles.

Question 8

What happens if muscles work too hard for a long time?

Answer 8

• They become fatigued and don’t contract efficiently.

- If they don’t get enough oxygen, they will respire anaerobically.

Question 9

What is anaerobic respiration?

Answer 9

• Respiration without oxygen.

- Takes place in animal cells, glucose is incompletely broken down to form lactic acid.

Question 10

Does the anaerobic breakdown of glucose transfer less energy than aerobic respiration?

Answer 10

Yes.

Question 11

Why is oxygen still needed for after exercise?

Answer 11

• To break down the lactic acid that has built up.

- The amount if oxygen needed is known as the oxygen debt.

Question 12

Anaerobic respiration in plant cells.

Answer 12

• Also in some microorganisms such as yeast.

- Results in the production of ethanol and carbon dioxide.

Question 13

What is the metabolism and what does it include?

Answer 13

• Sum of all the reactions in the body.
• Conversion of glucose to starch, glycogen and cellulose.
• Includes the formation of lipid molecules, and the use of glucose and nitrate ions to form amino acids, which are used to synthesise proteins, and breakdown excess proteins to from urea.

Question 14

What is the energy transferred by respiration in cells used by and what for.

Answer 14

• The organism.

- Used for the continual enzyme controlled processes of metabolism that synthesis new molecules.

Question 15

What happens when blood flows through the muscles?

Answer 15

• Transports lactic acid to the liver where it is converted back to glucose.