\date{}
\maketitle
- \subsection*{Carbohydrates}
+ \section{Vitamins}
+
+ \subsection*{Fat-soluble vitamins}
+
+ \begin{itemize}
+ \item Carbon and hydrogen
+ \item Non-polar (few or no polar groups)
+ \item Soluble in other non-polar solvents e.g. fats, oils
+ \item Can be synthesised endogenously
+ \end{itemize}
+
+ \subsection*{Water-soluble vitamins}
+
+ \begin{itemize}
+ \item Absorbed directly into bloodstream
+ \item Catalyse cellular reactions
+ \item Excreted through kidneys in urine
+ \item Must be obtained from food
+ \end{itemize}
+
+ \section{Proteins}
+
+ \begin{itemize}
+ \item All proteins contain C, H, O, N
+ \item Plants make proteins from inorganic compounds, animals cannot
+ \item Built from monomers called \textbf{amino acids}
+ \end{itemize}
+
+ \subsection*{Aminio acids}
+
+ \begin{itemize}
+ \item Contains amino (\ce{-NH2}) and carboxyl (\ce{-COOH})
+ \item Most have four groups bonded to central atom
+ \item May be polar or non-polar (amphoteric), acidic or basic
+ \item \textbf{Essential amino acids} - cannot be synthesised, must be supplied in diet
+ \item Amino acids (except glycine) are enantiomers due to chiral centres
+ \item Must be correct chirality to act as a biological catalyst
+ \end{itemize}
+
+ % amino acid general structure (see Jacaranda p.328)
+
+ \chemfig{{\color{red}N}(-[:135,,,,red]{\color{red}H})(-[:225,,,,red]{\color{red}H})-[:-45]C(-[:-90]\color{orange}\textit{R})(-H)-[:45]{\color{blue}C}(=[:90,,,,blue]{\color{blue}O})-[,,,,blue]{\color{blue}OH}}
+
+ \subsection*{Zwitterions}
+
+ \begin{itemize}
+ \item Zwitterion = \textit{dipolar ion}
+ \item Behaves as a base in acidic environments: \ce{-COOH- + H+ -> -COOH}
+ \item Behaves as an acid in basic environments: ammonium group loses \ce{H+} \(\implies\) anionic form
+ \end{itemize}
+
+ % Zwitterion structural equation (Jacaranda p.330)
+
+ \[ \ce{$\underset{\text{acid form}}{\ce{^+H3N-CH2-COOH}}$ <=>[+H+] $\underset{\text{zwitterion form}}{\ce{^+H3N-CH2-COO-}}$ <=>[-H+] $\underset{\text{basic form}}{\ce{H2N-CH2-COO-}}$} \]
+ \[ \text{cationic} \hspace{12cm} \text{anionic} \]
+
+ \subsection*{Formation of proteins}
+
+ \[ \text{Amino acid} \rightarrow \text{peptide} \tag{polymerisation} \]
+
+ Peptide group (amide): \ce{-C=ONH} (condensation reaction produces \ce{H2O})
+
+ Amino acid \textit{residue} - product of peptide formation reaction
+
+ Large polypeptides are called \textit{proteins}
+
+ \subsection*{Protein structure}
+
+ \begin{enumerate}
+ \item \textbf{Primary structure} - order of amino acids in peptide chain
+ \item \textbf{Secondary structure} - coils/pleats/folds in polymer
+ \item \textbf{Tertiary structure} - three-dimensional structure, e.g. H-bonding, ionic bonding
+ \item \textbf{Quaternary structure} - arrangement of multiple protein molecules
+ \end{enumerate}
+
+ % diagram of structural levels (Jacaranda p.332)
+
+ \subsection*{Enzymes}
+
+ \begin{itemize}
+ \item Biological catalysts (lowers \(E_A\))
+ \item Names usually end in \textit{-ase}
+ \item Every enzyme has a unique 3D shape
+ \item Rate of reaction \(\propto\) concentration up to \textit{saturation point}
+ \item \textbf{Substrate} - reactant molecule
+ \item \textbf{Active site} - destination of substrate
+ \end{itemize}
+
+ % enzyme catalyst diagram (Jacaranda p.334)
+
+ \subsubsection*{Lock and key model}
+
+ Reactants and enzymes must have complementary shapes
+
+ \subsubsection*{Indicued fit model}
+
+ Active site may change to fit subtrate
+
+ \subsection*{Coenzymes}
+
+ "Helper" molecules to enzymes. Non-protein molecules. Temporarily forms a loose bond with protein molecule to form active enzyme. Coenzymes are not specific to the substrate (different to enzymes).
+
+ \section*{Digestion of protein}
+
+ Proteins are hydrolysed by the \textit{pepsin} enzyme (\(\implies\) addition of \ce{H2O}).
+
+ \begin{description}
+ \item [Hydrolysis:] breaking of strong covalent (peptide) bonds
+ \item [Denaturation:] breaking of weak bonds (dispersion, H-bonds)
+ \end{description}
+
+ \section{Carbohydrates}
\subsubsection*{Monosaccharides}