Option B: Biochemistry

• Amino acids are amphoteric and can exist as zwitterions, cations and anions.
• Proteins are polymers of 2-amino acids, joined by amide links (also known as peptide bonds).
• Biopolymers form by condensation reactions and are broken down by hydrolysis reactions.
• Fats are more reduced than carbohydrates and so yield more energy when oxidized.
• Triglycerides are produced by condensation of glycerol with three fatty acids and contain ester links.
• Steroids have a characteristic fused ring structure, known as a steroidal backbone.
• Lipids act as structural components of cell membranes, in energy storage, thermal and electrical insulation, as transporters of lipid soluble vitamins and as hormones.
• Monosaccharides contain either an aldehyde group (aldose) or a ketone group (ketose) and several OH groups.
• Straight chain forms of sugars cyclize in solution to form ring structures containing an ether linkage.
• Glycosidic bonds form between monosaccharides forming disaccharides and polysaccharides.
• Xenobiotics refer to chemicals that are found in an organism that are not normally present there.
• Hostguest chemistry involves the creation of synthetic host molecules that mimic some of the actions performed by enzymes in cells, by selectively binding to specific guest species, such as toxic materials in the environment.
• Enzymes have been developed to help in the breakdown of oil spills and other industrial wastes.
• Protein assays commonly use UV-vis spectroscopy and a calibration curve based on known standards.
• Amino acids and proteins can act as buffers in solution.
• Polynucleotides form by condensation reactions.
• zwitterions are neutral molecules with both positive and negative charges
• zwitterions in amino acids increase solubility due to the presence of both polar and non-polar groups, forming H-bonds.
• zwitterions in amino acids increase melting point when in solid state due to H-bonds
• photosynthesis reactions are anabolic
• respiration reactions are catabolic
• The pH at which an amino acid is neutral is the isoelectric point
• if the pH of the amino acid is greater than at isoelectric point (pH>pH @) the amino acid is an anion
• if the pH of the amino acid is less than at isoelectric point (pH<pH @) the amino acid is a cation
• Hydrophobic interactions in protein structures occur between non-polar side chains
• hydrogen bonding in protein structures occur between polar side chains or between N, O or F
• ionic bonding between protein structures occur between charged side chains
• Disulfide bridges between protein structures occur between side chains of cysteine which contain sulfhydryl group (CH2-SH)
• the stationary phase in chromatography is the material that the solvent moves through
• the mobile phase in chromatography is the solvent that moves through the stationary phase
• different amino acids separate according to how they absorb into the stationary phase vs how readily they dissolve in the mobile phase
• the amino acid that adsorbs strongly in the stationary phase won't travel as far up the paper
• the amino acid which is more soluble in the mobile phase will travel further up the paper
• Lipids are a broad group of biomolecules that are largely non-polar and therefore insoluble in water.
• Hydrolysis of triglycerides and phospholipids can occur using enzymes or in alkaline or acidic conditions.
• Monosaccharides contain either an aldehyde group (aldose) or a ketone group (ketose) and several OH groups.
• Straight chain forms of sugars cyclize in solution to form ring structures containing an ether linkage.
• Glycosidic bonds form between monosaccharides forming disaccharides and polysaccharides.
• vitamin C is water-soluble because of the presence of OH groups and an ester fragment that forms H-Bonds in water
• Vitamin A is fat-soluble due to hydrophobic and retinoids, while vitamin D is a group of compounds called secosteroids.