Glycolysis

• energy

• Structural or functional molecules

• Storage compounds

• Energy derived from oxidation of Carbohydrates fat and protein

• 60-70% of energy is lost

• Reminder stored as ATP

Destinations for the nutrients we eat

• all chemical reactions in the body

• All molecules have energy stored in the bonds between their atoms

• Chemical reactions depend on transfer of small amounts of energy from one molecule to another

• Transfer by ATP

Metabolism/ metabolic reactions

• chemical reactions that break down complex organic molecules

Catabolism

• chemical reactions that build up simple molecules into complex molecules

Anabolism

• temporary storage for energy

• 3 phosphates attached to an adenine base and 5c sugar

• Used for muscle contraction, active transport,movement of structures within a cell

• ATP → ADP + iP

ATP

• large molecules - smaller units

• E.g proteins - peptides and amino acids

Stages of energy generation - first stage

• smaller units are degraded to a few simple key compounds that plays central role in metabolism

Stages of energy generation - second stage

• citric acid (kerbs) cycle

• Oxidative phosphorylation

Stages of energy generation - third stage

• during digestion polysaccharides or disaccharides are converted to monosaccharide s

• Glucose + oxgyen gas = water + carbon dioxide + atp + heat

Carbohydrates metabolism

• glycolysis

• Krebs cycle

• Electron transport chain

• Oxidation phosphorylation

Ways that glucose catabolises

• metabolic pathways synthesise ATP

• Anaerobic - atp production in a sense of oxygen - glycolysis, formation of acetyl CoA as transitional step

  Aerobic - ATp production using oxgyen - oxidative phosphorylation

• Fuel + oxgyen → carbon dioxide + water + heat

Cellular respiration

• glucose + 2NAD + 2ADP + 2iP 2 Pyruvic acid + 2NADH + 2ATP

• Initial step - activate glucose - (+2 phosphate groups)

• Initial step - activate glucose (+2 phosphate groups)

• Later in glycolysis - 4ATP (+2NADH2) liberated as energy

• (4-2) =2 2ATP + 2NADH2

Glycolysis equation

• sugar activation

• Two atp molecules are used to activate glucose

Glycolysis - Phase 1

• 6C sugar is split into two 3c sugars

• Each 3c sugar has a phosphate groups

• Inorganic phosphate groups are attached to each oxidised sugar fragment

Glycolysis - phase 2

• phosphates are split from the sugar and captured by ADP to form 4 ATP molecules

• Reminining 3C sugars are pyruvic acid

Glycolysis - phase 3

• 2 pyruvic acid molecules

• 2 NADH + H+ molecules

• A net gain of 2 ATP molecules

• If O2 is avaliable - pyruvic acid prepares to enter Kreb’s cycle

• If no O2 - pyruvic acid accepts the hydrogen from NADH2 to form lactic acid

Final products of glycolysis

• depends on oxgyen avaliablity

• If oxygen is not avaliable - reduced to lactic acid, which diffuses into blood and remove by liver and converted to pyruvic acid

• Oxgyen avaliable - pyruvic acid proceeds to the Krebs cycle in the mitochondrion

Fate of pyruvic acid

• phosphfructose kinase

• hexokinase

• pyruvate kinase

• irreversible

• all negative g values

glycolysis regulatory steps