Respiration
Respiration
LO:
• State the uses of energy in the body of humans: muscle contraction, protein synthesis, cell division, active transport, growth, the passage of nerve impulses and the maintenance of a constant body temperature
• State that respiration involves the action of enzymes in cells
LO:• Define aerobic respiration as the chemical reactions
in cells that use oxygen to break down nutrient molecules to release energy
• State the balanced chemical equation for aerobic respiration as
C6 H12 O6 + 6O2 → 6CO2 + 6H2 O• Investigate the uptake of oxygen by respiring
organisms, such as arthropods and germinating seeds• Investigate the effect of temperature on the rate of
respiration of germinating seeds
LO:
• Define anaerobic respiration as the chemical reactions in cells that break down nutrient molecules to release energy without using oxygen
• State the balanced chemical equation for anaerobic respiration in the microorganism yeast as C6 H12 O6 → 2C2 H5 OH + 2CO2
• State that anaerobic respiration releases much less energy per glucose molecule than aerobic respiration
LO:
• State that lactic acid builds up in muscles and blood during vigorous exercise causing an oxygen debt
• Outline how the oxygen debt is removed during recovery
LO: define the term respiration
RESPIRATION• the set of chemical reactions that break down
nutrient molecules in living cells to release energy
• Definition: respiration is the release of energy from food substances, and goes on in all living cells
• respiration involves the action of enzymes in cells
Energy= capacity for doing work- Needed for life- Source of energy = sun- Energy conversions:
- First conversion = photosynthesis- Second conversion = respiration
LO: State the uses of energy in the body of humans
THE USE OF ENERGY• Growth (proteosynthesis) – protein synthesis• Maintenance of a constant body temperature• Active transport• Cell division• Movement – muscle contraction• The passage of nerve impulses
LO: Know the form of energy found in human body
ATPAdenosine triphosphate• Small packet of energy which can drive the
reactions in a cell• Short-term store of energy
LO: Define aerobic respiration ;State the balanced chemical equation for aerobic respiration
AEROBIC RESPIRATION
• the release of a relatively large amount of energy in cells by the breakdown of food substances in the presence of oxygen
• chemical reactions in cells that use oxygen to break down nutrient molecules to release energy
• Takes place in mitochondria• Some energy is lost as heat
LO: Define anaerobic respiration; state the word equation
ANAEROBIC RESPIRATION• the release of a relatively small amount of energy by the
breakdown of food substances in the absence of oxygen
Word equation:• in muscles during hard exercise
glucose → lactic acid
• microorganism yeast glucose → alcohol + carbon dioxide
LO: State the balanced chemical equation for anaerobic respiration in the microorganism yeast as
• balanced chemical equation for anaerobic respiration in the microorganism yeast
C6 H12 O6 → 2C2 H5 OH + 2CO2
• Glucose alcohol and carbon dioxide
• Anaerobic respiration releases much less energy per glucose molecule than aerobic respiration!!!
LO: State that lactic acid builds up in muscles and blood during vigorous exercise causing an oxygen debt
OXYGEN DEBT
• Lactic acid produced by muscles during anaerobic respiration is carried out of the muscles in the blood
• It is transported to the heart, liver and kidneys and is oxydated to pyruvate
• Heart, liver and kidneys need extra oxygen to get rid of the lactic acid, provided by the deep fast breathing that follows hard exercise
• HOMEWORK:• Pages 52-53 Describe the role of anaerobic
respiration in yeast during brewing and bread-making.