cell respiration

what is cell respiration

the controlled release of energy from organic compounds to produce ATP

it’s ‘controlled’ cuz of enzymes

what ‘factor’ measures the efficiency of cell respiration?

the yield of ATP

  • i think higher yield of ATP = more efficient cell respiration


what’s a respiratory substrate?

any molecule that can be broken down in respiration to release energy

  • is usually glucose or carbohydrates, but can also be lipids of fatty acids, or proteins (as a last resort, cuz they hv other functions elsewhere in the cell)


what is one type of cellular respiration in humans?

Aerobic respiration

  • occurs in the presence of oxygen

  • has a high yield of ATP (cuz the breakdown of glucose results in high amounts of ATP)

    • approx. 36-38 ATP molecules are produced

  • begins in cytoplasm, but most of the steps occur in mitochondria

  • can use any respiratory substrate

  • waste products: carbon dioxide and water

  • word equation: glucose + oxygen = (arrow) carbon dioxide + water


what is the other type of cellular respiration in humans?

Anaerobic respiration

  • occurs without oxygen

  • produces a low yield of ATP (breakdown of glucose produces small amount of ATP)

    • approx. 2 ATP molecules are produced

  • can only use glucose & other carbs as respiratory substrate

  • occurs only in cytoplasm

  • waste products: lactate (lactic acid)

  • word equation: glucose = (arrow) lactate/lactic acid


what are some variables that affect the rate of cellular respiration?

temperature, pH, substrate concentration & oxygen concentration

  • since respiration is a series of enzyme-controlled reactions, the rate of respiration is affected by many of the same factors that affect any enzyme-controlled reaction


are gas exchange & cell respiration the same?

no, they’re different processes

Cell respiration: a chemical process occurring within the cell, and is the release of energy from carbon compounds within cell


gas exchange: the movement of oxygen & carbon dioxide between the air and blood in lungs, and involves gases passively moving by diffusion across a surface