Biological molecules
- Created by: ZoeKing98
- Created on: 06-05-16 14:38
View mindmap
- Biological molecules
- Protein
- Monomers amino acids
- Polymer: polypeptide joined during polymerisation by peptide bonds
- Amine group
- Carboxyl group
- 'R' group
- 20 amino acids
- Primary structure: sequence of amino acids, specfic for each protein
- Secondary structure: type of folding (e.g. beta pleated sheets or alpha helix)
- Tertiary structure: 3D shape after further folding
- Quaternary structure: more than one tertiary structures coming together
- Sometimes has a prosthetic group (e.g. iron ions in a haem group)
- Hyorogen bonds are numerous but easily broken
- Strong disulfide bridges can form
- Ionic bonds can form between unbonded caroboxyl and amine groups, broken by pH changes
- Quaternary structure: more than one tertiary structures coming together
- Occurs due to attraction from poles forming hydrogen bonds between N and O in the amine and carboxyl groups
- Tertiary structure: 3D shape after further folding
- Determined by DNA
- Secondary structure: type of folding (e.g. beta pleated sheets or alpha helix)
- Monomers amino acids
- Water
- Polar - oxygen slightly negative and hydrogens slightly positive
- Two sets of lone pairs
- Can form hydrogen bonds
- Bond angle 104.5 degrees
- Cohesion between molecules ('sticking' together)
- High laten heat of vaporisation and fusion
- Solvent
- High specific heat capacity
- Metabolite - breaks down and builds up molecules / compoufnds
- Carbohydrates
- Monomer: monosaccharide
- Fructose
- Form sucrose together
- Glucose (alpha and beta)
- 2 together form maltose
- Form lactose together
- Glucose (alpha and beta)
- Form sucrose together
- Galactose
- Form lactose together
- Glucose (alpha and beta)
- 2 together form maltose
- Fructose
- Polymer: polysaccharide
- Starch
- Amylose
- Coiled alpha glucose held together by hydrogen bonds (1-4 glycosidic bonds allow the coiled structure)
- Amylopectin
- Branched alpha glucose (1-6 glycosidic bonds allowing branching)
- Insoluble - has no effect on water potential
- Amylose
- Glycogen
- Branched
- Energy storage for animals
- Cellulose
- Structrual in plants
- Beta glucose bonded in altervative orientations
- Monomers bonded by glycosidic bonds
- Condensation reaction occurs (water molecule is formed)
- Bonds broken by hydrolysis - addition of water
- Starch
- Monomer: monosaccharide
- Lipids
- Monomers: glycerol and fatty acids
- Polymer: typically 1 glycerol group and three fatty acid 'tails' - triglycerides
- Saturated - all single bonds. Typically solid at room temp (fat)
- Unsaturated - mono: 1 double bond; poly: more than 1. Typically liquid at room temp (oils)
- Low mass to energy ratio so 'light' to carry
- Phospholipid polymer: 1 glycerol, 2 fatty acids and a phosphate group - found in membranes
- Hydrophobic 'tail'
- Hydrophilic 'head'
- Polar
- Ester bonds between glycerol and fatty acids
- Polymer: typically 1 glycerol group and three fatty acid 'tails' - triglycerides
- Insoluble in water (so no effect on WP); soluble in organic solvents
- Energy source
- Waterproofing e.g. waxy cuticle
- Insulation
- Protection
- Triglycerides: high ratio of hydrogen to oxygen means an important source of water
- Emulsion test: add 5cm ethanol to 2cm liquid sample and shake before adding 5cm of water. A cloudy white precipitate indicates the presence of a lipid.
- Monomers: glycerol and fatty acids
- Protein
Similar Biology resources:
Teacher recommended
Comments
No comments have yet been made