B12.1 Respiration

What is cell respiration?

• Chemical reactions in cells that break down nutrient molecules to release energy

What is the energy released by respiration used for?

• Muscle contraction

• Protein synthesis

• Cell division and growth

• Active transport

• Passage of nerve impulses

• Maintenance of a constant body temperature

What is aerobic respiration?

• Chemical reaction in cells that use oxygen to break down nutrient molecules to release energy

• Takes place in the mitochondria

What is the word equation for aerobic respiration?

Glucose + Oxygen → Carbon dioxide + Water + ATP

What is the balanced equation for aerobic respiration?

C₆H₁₂ + 6O₂ → 6CO₂ + 6H₂O

What is anaerobic respiration?

• Chemical reaction in cells that break down nutrient molecules to release energy without using oxygen

• They release a lot less energy for each glucose molecule used

What is the word equation for anaerobic respiration?

Glucose → Lactic acid + ATP

Explain what happens to the body during vigorous exercise

• Anaerobic respiration occurs in muscle cells during vigorous exercise, since cells cannot obtain enough oxygen for aerobic respiration to occur

• This causes lactic acid (waste product) to build up in the muscles during anaerobic respiration

  • Lactic acid is dangerous to the body and needs to be broken down

What is oxygen debt?

• The amount of oxygen needed to break down lactic acid in the liver

How can you remove lactic acid from the body?

• Aerobic respiration in the liver breaks down lactic acid into carbon dioxide and water

• Heart rate remains high after exercise to transport lactic acid from muscles to liver

• Breathing remains deep and fast to supply the oxygen needed for lactic acid to be broken down