Session 1 Flashcards
Discuss the bonds important for macromolecular structure and interaction
Covalent (disulphide) Ionic Hydrophobic interactions Van der Waals Hydrogen bonds
Identify the main organelles in a mammalian cell and list their functions
Cytoplasm - metabolism of carbohydrates, amino acids, nucleotides, fatty acid synthesis
Nucleus - RNA synthesis, RNA processing and ribosome assembly, DNA synthesis and repair
Lysosomes - cellular digestion
Endoplasmic reticulum - lipid and steroid synthesis, membrane synthesis, export of proteins, protein synthesis, detoxification
Golgi complex - export of proteins, detoxification
Ribosomes - protein synthesis
Mitochondria - ATP synthesis
Plasma membrane - transport of ions and small molecules, cell morphology and movement
Explain the differences between hydrophobic and hydrophilic molecules in water
Hydrophobic - non-polar molecule unable to interact with water
Hydrophilic - polar molecules that can interact with water
Amphiphatic - contain both polar and non-polar regions
Explain the concept of pH, pk and buffers
pH - -log[H+]
pK - strength of an acid in solution
Buffers - resists changes to pH on addition of small amounts of acid or alkali
Recognise and draw the generalised structure of an amino acid
NH2, C, R, H, COOH
Classify amino acids according to the properties of their side chains and explain how the charge on amino acids is affected by pH
Aromatic Polar, uncharged Nonpolar, aliphatic Negatively charged Positively charged Isoelectric point - pH when a protein has no overall net charge
Show how a peptide bond is formed and list it’s key features
Trans orientation
No rotation about peptide bond
Atoms in the same plane
Explain how amino acid charge can influence the isoelectric point of a protein
Negatively charged amino acids = acidic protein = low pI
Positively charged amino acids = basic protein = high pI
Describe what is meant by the primary, secondary, tertiary and quaternary structure of proteins
Primary - sequence of amino acids
Secondary - local spatial arrangement (a-helix, B-pleated sheet)
Tertiary - 3D arrangement
Quaternary - 3D arrangement of multi-subunit proteins
Describe the types of bonds and forces involved in protein structure and how their disruption can lead to protein denaturation
Covalent - reducing agents
Ionic - pH, ionic strength
Hydrophobic interactions - detergent, organic solvent
Hydrogen bonds - pH
Explain the key features of the two major secondary structure elements of proteins (a-helix and B-sheet)
A-helix - right handed, 3.6aa per turn, 5.4nm pitch
B-sheet - extended conformation, parallel or anti parallel
Recognise the importance of protein folding in correct protein function
Misfolded proteins don’t give the correct function
