Biochemistry Final Exam Notes.[COMPLETELY AND 100% VERIFIED]

Biochemistry Final Exam Notes CHEM225 Ch. 1: The Chemical Basis of Life - Amino acids are a major type of biological molecule. Amino acids contain an amino group, a carboxylic acid group and a side chain. - Carbohyd ...

Biochemistry Final Exam Notes CHEM225 Ch. 1: The Chemical Basis of Life - Amino acids are a major type of biological molecule. Amino acids contain an amino group, a carboxylic acid group and a side chain. - Carbohydrates are a major biological molecule. Carbohydrates are monosaccharides or sugars. General chemical formula: (CH2O)n, where n>3. - Nucleotides are the building blocks of nucleic acids. - Lipids have a variety of structures. One of the most important is cholesterol. - Monomers link sequentially to form polymers. • Three major kinds of biological polymers: - Polypeptides and proteins - Nucleic acid - Polysaccharides - Amino acids link to form polypeptide and proteins. Amino acid resides are connected via peptide bonds. Polypeptide sequences are always read from the N terminus to the C terminus. - Nucleotide residues link via phosphodiester bonds - Polymers of nucleotides yield nucleic acids - Polymers of sugars are polysaccharides linked with a glycosidic bond Key concepts: Section 1-3 - The free energy of a system is determined by its enthalpy and entropy. - Living organisms obey the laws of thermodynamics - Enthalpy, H !1Monday, March 14, 2016 • The heat content of a system • Units = J x mol-1 - Entropy, S • A measure of the systems disorder or randomness • Units= J x K-1mol-1 - Gibbs free energy, G • A measure of the free energy of a system based on H and S • Units = J x mol Basics of Thermodynamics - It is easier to measure thermodynamic changes than discrete values - ∆G= ∆H -T∆S • ∆G= Gibbs free energy change - The sign of ∆G is meaningful, when ∆G <0, the reaction is spontaneous or exergonic. - When ∆G > 0, the reaction is non spontaneous or endergonic. Coupled Chemical Reactions - ∆G is positive for the A—> B transition. Non spontaneous reactions do not generally occur. ∆G is negative for the B—>C transition. - Spontaneous reactions can be coupled with non spontaneous reactions so that the net reaction occurs spontaneously. Key Concepts: Section 1-4 - Modern prokaryotic and eukaryotic calls apparently evolved from simple non-living