Cellular respiration ( Catabolic)

Occurs in cytosol and mitochondria to catabloise orangic compounds aerobically/anaerobiliccally in from of ATP

1. Distinguish between aerobic and anaerobic respiration, including the presence or absence of oxygen and their respective energy yields.

Anaerobic respiration → fast short pace quick/small energy

• no oxygen

Aerobic respiration → slow long pace alot of energy

• oxygen

2. Outline the chemical processes of glycolysis, Krebs cycle, Electron transport chain

First step: Glycolysis ( Anaerobic) - splitting of glucose

Location: cytosol/cytoplasm

Reactants: 1 glucose

Products:

• 2 pyruvate

• lactic acid (cramp) in muscle

  • Also transported to the liver to combine with oxygen to form glucose → glycogen through aerobic respiration

ATP yield: net gain of 2 (needs 2 atp but gains 4 atp)

• Oxygen not required

The rest are Aerobic

Pyruvate oxidation → before entering next stage (precursor)

Pyruvate is mixed with Coenzyme A in the presence of oxygen to form Acetyl CoA → when 1 of the 3 CO2 is removed from pyruvate

• occurs in mitochondrion

• no atp in this process

• need oxygen

Second Step: Kerbs Cycle ( citric acid cycle)

Kerb cycle: Carbon atoms in acetyl CoA are released in carbon dioxide

location: outer membrane (matrix)

Reactants: 2 acetyl CoA ( cycles twice)

Products:– 2 CO₂, 3NADH and FADH₂ ( one every cycle)

ATP yield: Net gain of 2 (1 per cycle)

• Oxygen requried

Third Step: Electron transport chain

Electrons pass through molecules being removed resulting in oxygen forming water

Location: mitochondria - inner surface

Reactants: NADH and FADH² → produces during kerbs and glycolysis

Product:  H₂O

ATP yield: net gain of 26-34

• oxygen required and used to form water

3. Outline the different end products of aerobic and anaerobic respiration

4. Explain how ATP is used in the body as a source of energy

   Energy (produced in cellular resp. causes a phosphate (P) to bind to ADP which forms ATP (and water) When required by the cell the Phosphate group is removed changing ATP to ADP and releases energy to the cell

   60% of energy released as heat → body tempreature (homeostasis)

   40% of energy incorporated into ATP

   • Building complex molecules

   • Cell division and growth

   • Movement of cell organelles

   • Movement of whole cell

   • Maintaining cell organisation

   • Active transport

   • Transmission of nerve impluses

• ALl anabolic reaction reactions require catabolism of form of ATP to ADP