Bioenergetics

• Inverse square law

  Light intensity obeys the inverse square law
• Uses of glucose

  • Respiration
  • Produce amino acids
  • Produce cellulose for cell walls
  • Stored as starch
  • Produce fats/oils for storage
  • Produces glucose
• Limiting factors

  • Temperature
  • Light intensity
  • Carbon dioxide concentration
  • The amount of chlorophyll present
• Factors can interact, e.g. a higher light intensity can lead to a higher temperature
• Knowledge of these can help improve crop yield and make farming more efficient
• Endothermic
• Increasing the supply of a limiting factor

  Increases the rate of photosynthesis
• Light intensity


  Proportional to 1/distance^2
• Higher light intensity


  More energy for photosynthesis
• Respiration


  The sum of all metabolic reactions in a cell or an organism
• Respiration

  • Function
  • Exercise
  • Metabolism
  • Synthesis using glucose
  • Types
  • Produces ethanol
  • Fermentation
  • Need for energy
  • Anabolic Reactions
  • Catabolic Reactions
  • Glycogen
  • Starch
  • Cellulose
  • Synthesis of lipids
  • Glycerol
  • 3 Fatty Acids
  • Synthesis of Amino Acids
  • Requires glucose and nitrates
  • Making proteins
  • Excess proteins are broken down to urea
  • Higher demand for energy
  • Higher Heart rate
  • Breathing rate
  • Breath volume
  • Supply oxygenated blood at a higher rate to muscles
  • May lead to insufficient oxygen
  • Build up of lactic acid
  • Oxygen debt
  • Muscle fatigue
  • Lactic acid is converted to glucose
  • Additional volume of oxygen needed to react with lactic acid to remove it from the cells
  • Larger molecules broken down into smaller ones
  • Joining of small molecules to form larger molecules
• Aerobic


  Respiration that requires oxygen
• Anaerobic


  Respiration that does not require oxygen
• Fermentation


  A type of anaerobic respiration that produces ethanol
• Glucose + oxygen


  → Carbon dioxide + water
• Produces less energy

  Anaerobic respiration
• Produces more energy

  Aerobic respiration
• Exothermic

  Releases energy
• Glucose


  → Ethanol + carbon dioxide
• Glucose


  → Lactic acid
• Anabolic reactions


  Reactions that build up larger molecules from smaller ones
• Catabolic reactions


  Reactions that break down larger molecules into smaller ones
• Glycogen


  A polysaccharide that serves as a form of energy storage in animals, fungi, and bacteria
• Starch


  A polysaccharide that serves as a form of energy storage in plants
• Cellulose

  A polysaccharide that is the main structural component of the cell walls of green plants
• Synthesis of lipids


  The process of forming lipids from smaller molecules
• Glycerol


  A simple sugar alcohol that is used as a sweetener and in the manufacture of other chemicals
• 3 Fatty Acids

  A carboxylic acid with a long aliphatic chain, which is either saturated or unsaturated
• Synthesis of Amino Acids


  The process of forming amino acids from smaller molecules
• Requires glucose and nitrates


  Making proteins
• Excess proteins are broken down to urea


  Removing excess proteins from the body
• Higher demand for energy

  Increased need for energy in the body
• Higher Heart rate

  Increased rate of heartbeat
• Breathing rate

  Increased rate of breathing
• Breath volume

  Increased volume of air inhaled and exhaled
• Supply oxygenated blood at a higher rate to muscles

  Increased supply of oxygenated blood to the muscles
• Higher demand for energy

  • Higher Heart rate
  • Breathing rate
  • Breath volume
  • Supply oxygenated blood at a higher rate to muscles
• May lead to insufficient oxygen

  Lack of oxygen in the body
• Build up of lactic acid


  Accumulation of lactic acid in the body
• Oxygen debt


  The amount of oxygen needed to restore the body to its normal state after exercise