i. Acid catalyzed Hydration (Markovnikov) of propyne. ii. Esterification reaction iii. Ethylamine with HCL iv. Hydrogenation of alkenes 2a. Define the term "amphipathic' compound (1 mrks) b. Elucidate the variation of pH with temperature (2 mrks) c. State two thermodynamic quantities that contribute to the value for Delta G (2 mrks) d. Sketch a titration curve for acetic acid with a strong acid (3 mrks) 3a. Outline the biochemical roles of integrins b. State examples of primary active transport in the biological membrane (4 mrks) (4 mirks) 4a. Define the terms below in relation to enzymes (2 mrks) i. Substrate ii. Holoenzyme b. Illustrate the following concerning enzyme activity i. Allosteric regulation of enzymes activity (3 mrks) ii. pH dependency (3 mrks) 5a. State the general properties of nucleic acids (4 mrks) b. Draw a well -labelled diagram of the structure of eukaryotic mRNA molecule (4 mrks) SECTION C: LONG ANSWER QUESTIONS (40 MARKS).QUESTION ONE:IS COMPULSORY, THEN CHOOSE EITHER QUESTION 2 OR 3. 1. Biological functions of a protein depend on the conformational changes of its structure. Discuss the four structural levels of proteins (20 mrks) 2. Glycolipids is one of the different types of lipids with significant biochemical functions in human being Discuss the structures and biochemical roles of the two major classes of glycolipids (20 mrks) 3. Cellulose and glycogen are two major examples of homopolysacch arides. Discuss their structure in relation to their biological functions in living organisms

1. i. Acid catalyzed Hydration (Markovnikov) of propyne:<br />The acid-catalyzed hydration of propyne follows the Markovnikov rule, where the hydrogen atom from the water molecule adds to the carbon atom of the triple bond that has the greater number of hydrogen atoms already attached to it. The reaction proceeds as follows:<br /><br />Propyne + H2O → 1-Propen-1-ol<br /><br />ii. Esterification reaction:<br />Esterification is the reaction between a carboxylic acid and an alcohol to form an ester and water. The general reaction is:<br /><br />Carboxylic acid + Alcohol → Ester + Water<br /><br />iii. Ethylamine with HCl:<br />When ethylamine reacts with hydrochloric acid (HCl), it forms the ethylammonium ion:<br /><br />CH3CH2NH2 + HCl → CH3CH2NH3+ + Cl-<br /><br />iv. Hydrogenation of alkenes:<br />Hydrogenation is the addition of hydrogen (H2) to an alkene, converting it into an alkane. The reaction is catalyzed by a metal catalyst such as platinum, palladium, or nickel.<br /><br />Alkene + H2 → Alkane<br /><br />2a. Define the term "amphipathic' compound:<br />An amphipathic compound is a molecule that has both hydrophilic (water-attracting) and hydrophobic (water-repelling) regions. This dual nature allows amphipathic compounds to interact with both polar and non-polar substances.<br /><br />b. Elucidate the variation of pH with temperature:<br />The variation of pH with temperature is generally small, but it can have significant effects on chemical equilibria and biological processes. As temperature increases, the concentration of hydrogen ions (H+) in a solution can increase, leading to a decrease in pH. Conversely, as temperature decreases, the concentration of H+ can decrease, resulting in an increase in pH.<br /><br />c. State two thermodynamic quantities that contribute to the value for ΔG:<br />The Gibbs free energy change (ΔG) is a thermodynamic quantity that measures the spontaneity of a chemical reaction. Two thermodynamic quantities that contribute to the value of ΔG are enthalpy (H) and entropy (S). The relationship is given by the equation:<br /><br />ΔG = ΔH - TΔS<br /><br />where T is the absolute temperature.<br /><br />d. Sketch a titration curve for acetic acid with a strong acid:<br />A titration curve for acetic acid with a strong acid would show a gradual increase in pH as the strong acid is added to the acetic acid solution. The curve would initially be relatively flat, representing the buffering capacity of the acetic acid. As more strong acid is added, the pH would decrease more rapidly, eventually leveling off at a lower pH.<br /><br />3a. Outline the biochemical roles of integrins:<br />Integrins are a family of transmembrane receptors that play crucial roles in cell adhesion, cell signaling, and cell migration. They mediate interactions between cells and the extracellular matrix, facilitating processes such as wound healing, immune response, and tissue development.<br /><br />b. State examples of primary active transport in the biological membrane:<br />Primary active transport is the movement of molecules across a biological membrane against their concentration gradient, using energy directly from an energy source such as ATP. Examples of primary active transport include the sodium-potassium pump (Na+/K+ ATPase) and the calcium pump (Ca2+ ATPase).<br /><br />4a. Define the terms below in relation to enzymes:<br />i. Substrate: The substrate is the specific molecule upon which an enzyme acts. The enzyme catalyzes the chemical reaction involving the substrate, converting it into one or more products.<br /><br />ii. Holoenzyme:oloenzyme is the complete, active form of an enzyme, consisting of the protein component (apoenzyme) and its associated cofactor or coenzyme. The holoenzyme is the functional form of the enzyme, capable of catalyzing its specific reaction.<br /><br />b. Illustrate the following concerning enzyme activity:<br />i. Allosteric regulation of enzymes activity:<br />Allosteric regulation involves the binding of a regulatory molecule (allosteric effector) to a site other than the active site of an enzyme. This binding induces a conformational change in the enzyme, altering its activity. Allosteric regulation can either activate or inhibit enzyme activity.<br /><br />ii. pH dependency:<br />Enzyme activity is sensitive to changes in pH. Each enzyme has an optimal pH range within which it exhibits maximum activity. Deviations from this pH range can lead to changes in the enzyme's structure, reducing its activity. Extreme pH values can denature the enzyme, rendering it inactive.<br /><br />5a. State the general properties of nucleic acids:<br />Nucleic acids are macromolecules that store and transmit genetic information. They are composed of nucleotides, which consist of a sugar, a phosphate group, and