AQA A-Level Biology Paper 1 Study Guide Exam Questions and Answers (41 Terms)

AQA A-Level Biology Paper 1




AQA A-Level Biology Paper 1 Study
Guide Exam Questions and Answers (41
Terms) 2024-2025
Describe the role of a ribosome in the production of a polypeptide. /3 - Answer: 1.
mRNA binds to ribosome;
2. Idea of TWO codons/binding sites;
3. tRNA with ANTICODONS binds;


1

, AQA A-Level Biology Paper 1


4. (Catalysis) formation of PEPTIDE bond between AMINO ACIDS (held by tRNA
molecules);
5. Moves along (mRNA to the next
codon);


Describe the structure of glycogen. /2 - Answer: 1. Polysaccharide of α-glucose;
OR
polymer of α-glucose;
2. (Joined by) glycosidic bonds
OR
Branched structure;


NHE3 actively transports one sodium ion into the cell in exchange for one proton
(hydrogen ion) out of the cell.
Use your knowledge of transport across cell membranes to suggest how NHE3
does this. /3 - Answer: 1. Co-transport;
2. Uses (hydrolysis of) ATP;
3. Sodium ion and proton bind to the protein;
4. Protein changes shape (to move sodium ion
and/or proton across the membrane);


Explain the curves for max protease activity over time at 50C and 60C. /4 -
Answer: 1. Both denatured (by high temperature);
2. Denaturation faster at 60 °C due to more (kinetic) energy;
3. Breaks hydrogen/ionic bonds (between amino acids/R groups);

2