IB DP Biology Mock Exam SL Paper 2 Set 4 - 2025 Syllabus
IB DP Biology Mock Exam SL Paper 2 Set 4
Prepare for the IB DP Biology Exam with our comprehensive IB DP Biology Exam Mock Exam SL Paper 2 Set 4. Test your knowledge and understanding of key concepts with challenging questions covering all essential topics. Identify areas for improvement and boost your confidence for the real exam
Question
A short base sequence of mRNA and a table of the genetic code are shown below Sequence of mRNA
$\text{AUGAGCCGAAGGUAGCUG}$
Table of the genetic code
a. Outline the function of codons.
b. (i) Determine the sequence of amino acids that could be translated from the sequence of mRNA.
b. (ii) Determine the DNA base sequence transcribed to form this sequence of mRNA.
c. Suggest a hypothesis that accounts for the slightly different meaning of some codons in a very limited number of organisms.
d. The diagram shows a section of a polypeptide
(i) Annotate the diagram to show a peptide bond between two amino acids.
(ii) State the type of reaction that removes water while linking amino acids together to form polypeptides.
e. Outline the function of Rubisco and of spider silk in relation to their three-dimensional conformation.
Function | Conformation | |
Rubisco | ||
Spider silk |
Answer/Explanation
Ans:
a) «three bases on mRNA» coding for one amino acid «in a polypeptide»
b i) met-ser-arg-arg
OR
start-ser-arg-arg
OR met-ser-arg-arg-stop
OR start-ser-arg-arg-stop Do not accept peptides containing an amino acid/leu for the last codon.
ii) TAC TCG GCT TCC ATC GAC
c) they occurred after the common origin of life OWTTE
OR
the genetic code is not «in fact» universal Look for alternatives.
d i) any annotation between a C=O and the next NH
ii) condensation
e) 