Biology Aqa As Level7401/1 Paper 1 |24 Questions| With Correct Answers.

Many people with Alzheimer's disease have mutations that decrease α-secretase production or increase β-secretase production (lines 8-9). Use the information provided to explain how these mutations can lead to Alzheimer's disease. {Ans: - Mutations prevent production of enzyme - (Increase in β-secretase) leads to more β-amyloid production - (Leads to) more/greater plaque formation}Describe how a saturated fatty acid is different from an unsaturated fatty acid {Ans: Unsaturated has (at least one) double bond (between carbons)}Y is a protein. One function of Y is to transport cellulose molecules across the phospholipid bilayer. Using information from Figure 3, describe the other function of Y. {Ans: - (Y is) an enzyme/has active site/forms ES complex; - That makes cellulose}One possible type of drug for treating Alzheimer's disease is a competitive inhibitor of β-secretase (lines 10-11). Explain how this type of drug could prevent Alzheimer's disease becoming worse. {Ans: - (Inhibitor) binds to active site of β-secretase - reduces production of β- amyloid/plaque}Chromosomes line up on the equator of the mitotic spindle in the... {Ans: Metaphase}name the part of the mitochondrion labelled X in Figure 2 {Ans: Crista/cristae}In the cell wall, bonds hold the cellulose molecules together side