AQA Biology AS Level Exam style Answers
Topic 2- Pages 38-39
1a. A is a substrate for the enzyme as it has the complementary shape to fit into it.
1b. The non-competitive inhibitor decreases the RoR as it binds to somewhere else than the active site and then causes the active site to change shape meaning the substrate is no longer complementary so it wouldn’t bind together.
1ci. Peptide
1cii. The 35 and 52 amino acids are held close to form the active site due to the tight folding of the polypeptide chains
2ai. There will be more kinetic energy which means there wil be more successful collisions and then more enzyme-substrate complexes.
2aii. The enzyme is denatured, this means that the substrate will no longer fit into the active site and is no longer complementary.
2b. The curves level out as the same value as the RoR us quicker so the active sites get full quicker, the same thing happens at 27 but it happens slower due to less heat and therefore less kinetic energy, the mass is exactly the same.
3a. There is a lower activation energy so the molecules are brought tighter together.
3bi. 4=48 5=57 8=53
3bii. At pH 4 there is an increase in the kinetic energy up to the optimum level, this is where the enzyme is working most efficient and will be having successful collisions with each other and therefore creating more enzyme-substrate complexes. After 48 degrees the enzyme will denature and will not work as effectively.
4a. All of the active sites are full
4b. The non-competitor inhibitor attaches to the enzyme at a different place than the active site, this then makes the active site change it shape so its no longer complementary and then it prevents the formation of enzyme-substrate complexes.
4c. 2/7.6= 2.63x 100= 26.3%
4d
1a. A is a substrate for the enzyme as it has the complementary shape to fit into it.
1b. The non-competitive inhibitor decreases the RoR as it binds to somewhere else than the active site and then causes the active site to change shape meaning the substrate is no longer complementary so it wouldn’t bind together.
1ci. Peptide
1cii. The 35 and 52 amino acids are held close to form the active site due to the tight folding of the polypeptide chains
2ai. There will be more kinetic energy which means there wil be more successful collisions and then more enzyme-substrate complexes.
2aii. The enzyme is denatured, this means that the substrate will no longer fit into the active site and is no longer complementary.
2b. The curves level out as the same value as the RoR us quicker so the active sites get full quicker, the same thing happens at 27 but it happens slower due to less heat and therefore less kinetic energy, the mass is exactly the same.
3a. There is a lower activation energy so the molecules are brought tighter together.
3bi. 4=48 5=57 8=53
3bii. At pH 4 there is an increase in the kinetic energy up to the optimum level, this is where the enzyme is working most efficient and will be having successful collisions with each other and therefore creating more enzyme-substrate complexes. After 48 degrees the enzyme will denature and will not work as effectively.
4a. All of the active sites are full
4b. The non-competitor inhibitor attaches to the enzyme at a different place than the active site, this then makes the active site change it shape so its no longer complementary and then it prevents the formation of enzyme-substrate complexes.
4c. 2/7.6= 2.63x 100= 26.3%
4d