Aqa A Level Biology 4/5/6 Mark Questions Questions And Answers 100% Verified A+ Guaranteed

Explain how oxygen is loaded, transported and unloaded in the blood (6) {Ans: 1. Haemoglobin carries oxygen / has a high affinity for oxygen / oxyhaemoglobin; 2. In red blood cells; 3. Loading / uptake/association in lungs; at high p.O2; 4. Unloads / dissociates / releases to respiring cells / tissues; 5. at low p.O2; 6. Unloading linked to higher carbon dioxide (concentration);}Scientists have investigated the effects of competitive and non-competitive inhibitors of the enzyme maltase. Describe competitive and non-competitive inhibition of an enzyme. (5) {Ans: 1. Inhibitors reduce binding of enzyme to substrate / prevent formation of ES complex; (Competitive inhibition), 2. Inhibitor similar shape (idea) to substrate; 3. (binds) in to active site (of enzyme); 4. (Inhibition) can be overcome by more substrate; (Non-competitive inhibition), 5. Inhibitor binds to site on enzyme other than active site; 6. Prevents formation of active site / changes (shape of) active site; 7. Cannot be overcome by adding more substrate;}How does temperature affect the speed of a nerve impulse? (5) {Ans: 1. The higher the temperature the faster the nerve impulse; 2. Sodium-potassium pump uses active transport; 3. Which requires energy from ATP from respiration; 4. Respiration is enzyme-controlled;