Cellular Respiration

Aerobic Anaerobic Respiration Respiration

Cellular Respiration

Respiration is the slow controlled release of energy from food.

The energy released is used to fuel all metabolic activities in the organism.

The process takes place in many steps all ofwhich is controlled by enzymes.

Aerobic RespirationThe process by which glucose is oxidised in many small steps to give carbon dioxide and water.

C6H12O6 + 6O2 6CO2 + 6H20 + EnergyGlucose + Oxygen Carbon + Water + Energy

Dioxide

ADP + P(Phosphate) + EnergyEnergy (released)

ATP

ADP = Adenosine Di PhosphateATP = Adenosine Tri Phosphate.

ATP Is found in all cellsYields large amounts of energyDrives the thousands of biological processes needed to sustain life

eg. Growth, movement, reproduction.Green plants use light energy to manufacture ATP as part of the process of PhotosynthesisIn Animals, ATP is formed by the breakdown of glucose molecules in respiration

Summary of important events taking place in aerobic respiration

1.Glucose (or fat) is used as a substrate to provide energy

2.Energy is released in a slow, controlled process

3.The energy released is temporarily stored in ATP

4.Oxygen is used in the process5.Carbon dioxide and water is released

Anaerobic Respiration

In anaerobic respiration the food is broken down without oxygen in animals to form lactic acid and ethanol in plants and yeast.Lactic acid build up is toxic in animals and needs to be broken down. It usually builds up during strenuous exercise when oxygen is short (Oxygen debt).

Plants and Yeast ethyl alcohol + Carbon Dioxide + Energy2C2H5OH + 2 CO2

GlucoseC6H12O6

Animals Lactic acid + Energy2C3H6O3

Oxygen Debt

This occurs when the lungs cannot supply all the oxygen that the muscles need eg. During vigorous exercise.In such a situation the muscles can continue to break down glucose to liberate energy for a short time using anaerobic respiration This produces lactic acidAt certain levels in the muscles lactic acid causes the sensation of fatigue (tiredness)Once vigorous exercise stops the accumulated lactic acid must be broken down, this uses up extra oxygenPanting or Yawning usually allows the body to take in this excess oxygen to ‘pay off’ the oxygen dept

Summary of events taking place in anaerobic respiration1. No oxygen is used2. Little energy is produced3. Alcohol and carbon dioxide are produced

by plants and yeast4. Only lactic acid is produced by animals

Industrial & Domestic Applications of Anaerobic Respiration

Fermentation. Yeast uses sugar as food and makes ethanol as a by

product of the reaction. Ethanol is found in beers, wine and sprits like whiskey and rum.

Fermentation of bacteria (lactobacillus) in the production of yogurt and cheese

Baking.The carbon dioxide produced by yeast is what makes

bread, pastries and cakes light and fluffy

Site of Cellular Respiration

Site of cellular respiration

Diagrams of Mitochondria found in all eukaryotic cells

Mitochondria

An Organelle found in cellsContains enzymes responsible for energy production during aerobic respirationFound in both plant and animal cells