7. The nucleotide monomer PHOSPHATE SUGAR Nucleic acids contain C, H & O in addition to N & P
8. Proteins 3 groups: Amino group, Carboxyl group & R-group When joined together they form peptide bonds Aside from the C, H, O & N in the base molecule, the R group may also contain S & P
9. Protein structure Primary structure The linear sequence of amino acids Secondary structure The type of peptide bond determines how sections of the protein fold – spiral helix / pleated sheet / random coils Shape reinforced by additional H bonds Tertiary structure Eventual 3D shape formed by folding Shape reinforced by additional H bonds Quanternary structure When a protein is formed by the interaction of 2 or more polypeptide chains
11. Elements of a plasma membrane carbohydrate chains glycolipid glycoprotein phospholipid bilayer protein channel cholesterol
12. How does it regulate molecular transport? Passive Transport Diffusion Osmosis Facilitated diffusion (channel, receptor & carrier mediated) Active Transport Primary (uses chemical energy) Secondary (uses electrochemical gradient)
17. Mitochondrion Energy supplying organelle Produces chemical energy in the form of adenosine triphosphate (ATP) through the process of cellular respiration Outer & inner membrane The inner membrane contains many folds to provide a larger surface area for energy production ATP produced by reactions on inner membrane Only in eukaryotes
20. Enzyme Structure Enzymes have an active site and a regulatory region The active site (formed by folds in the protein) is where substrate binds to the enzyme The regulatory region is where cofactors coenzymes or enzyme inhibitors can alter the function of an enzyme Substrate Products Active site Enzyme inhibitor Regulatory region
25. Light-dependent reaction Occurs in the grana Light energy is used to split water in to two H+ ions and O2 gas The O2 is released as waste With the power of the two free electrons One H+ ion fuses ADP to Pi to form ATP One H+ ion fuses to NADP to form NADPH
26. Light-independent stage Occurs in Stroma Does not need light, but NADPH and ATP from previous stage Needs CO2 and H+ions Sugar molecules are synthesised from CO2 CO2 = oxidised state (low E compound) C(H2O)n = reduced state (high E compound) NADPH (carrier H+) is the reducing agent ATP is the energy source
30. Glycolysis Occurs in cytosol – uses enzymes and vitamins as coenzymes 1 glucose (6C) converted to 2 pyruvate (3C) Forms 2 ATP & 2 NADH
31. Krebs Cycle Occurs in mitochondria Pyruvate initially broken down in to CO2 and Acetyl-coA Joins with 4C molecule to form 6 C molecule CO2 to form 5 C molecule, then again to form 4 C molecule Further oxidation takes place to reform original 4C Throughout cycle, constant oxidation is fusing hydrogen to carrier molecules NAD -> NADH and FAD -> FADH2
32. Electron Transport Occurs in inner membrane of mitochondria Produces 2-3 ATP per loaded receptor Electrons passed from one cytochrome to next until accepted by O2- to form water Return of released protons through ATP synthase carrier provides energy to produce ATP from ADP & Pi (phosphorylation)
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34. Anaerobic respiration (in humans) Occurs in muscles where oxygen supply exceeds demand The only stage that can occur is glycolysis So 1 glucose produces 2 ATP 2 NADH convert pyruvate to lactate (lactic acid) Lactate build up causes pH to fall and pain & muscle fatigue When activity returns to normal and oxygen becomes available, lactate converted back to pyruvate to enter the Krebs Cycle.
35. Anaerobic respiration (in yeast) Anaerobic respiration in yeast is called fermentation Pyruvate is broken down in to CO2 and ethanol (alcohol)
