B9: Respiration

Question 1

What is the equation for aerobic respiration?

Answer 1

Glucose + Oxygen —> Carbon Dioxide + Water + Energy
C6H12O6 + 6O2 - 6CO2 + 6H20 + Energy

Question 2

What is respiration?

Answer 2

It is the process of transferring energy from the breakdown of glucose, taking place in the mitochondria. It is an exothermic reaction as energy is released to the environment.

Question 3

What is the energy from respiration used for?

Answer 3

• Carry out the basic functions of life, e.g. breaking or building up large molecules.
• Used for muscle contraction and movement/exercise.
• Maintain constant internal body temperature.
• Used for active transport of nitrates in plants and to make proteins from sugars/nitrates.

Question 4

How do muscles use energy for its function?

Answer 4

Muscle tissue is made of protein fibres that contract, requiring a lot of energy meaning they contain many mitochondria.
Muscles store glucose as glycogen which can quickly be converted back to glucose during exercise when it is needed.

Question 5

How does the body respond to exercise?

Answer 5

• Heart rate increases to allow arteries to supply more oxygenated blood to the exercising muscles, as well as increasing the amount of carbon dioxide removed.
• Breathing rate increases to take in oxygen and remove carbon dioxide at a quicker rate.
• Glycogen is converted back to glucose for more respiration and energy.

Question 6

What is the equation for anaerobic respiration?

Answer 6

Animals: Glucose -> Lactic Acid + Energy
Plants: Glucose -> Ethanol + Carbon dioxide

Question 7

What is the difference between aerobic and anaerobic respiration?

Answer 7

Anaerobic respiration produces less energy and there is not enough oxygen so the oxidation of glucose is incomplete.

Question 8

What is oxygen debt?

Answer 8

The amount of oxygen the body needs to break down and remove the lactic acid produced during anaerobic respiration. Carried out by taking quick, short breaths. Blood flowing through muscles transport lactic acid to the liver to be converted back to glucose.

Question 9

What is metabolism and examples?

Answer 9

• It is the sum of all chemical reactions taking place in a cell or in the body, usually making larger molecules from smaller ones or breaking down large molecules.
- Respiration/Photosynthesis
- Formation of lipid molecules
- Breakdown of excess proteins in the liver
- Forming amino acids to make proteins from glucose and nitrates
- Converting glucose into starch/glycogen/cellulose.