The genetic code and protein synthesisEdexcel A-Level Biology A: Flashcards

What these 14 flashcards ask

What is a gene?
What is a codon?
What does 'triplet code' mean?
What does 'degenerate' mean?
What does 'non-overlapping' mean?
What is the template (antisense) strand?
What does RNA polymerase do?
How does mRNA leave the nucleus?
What is the start codon?
What happens at a stop codon?
What is an anticodon?
What does tRNA do?
What is the mRNA made from template TAC GGA?
How many nucleotides does mRNA need for 10 amino acids plus a stop codon?

Exam questions on The genetic code and protein synthesis

The base sequence of a short section of the template (antisense) strand of a gene is TACCGAGGTATT. This section is transcribed to make mRNA that begins with a start codon and ends with a stop codon.
The codons GCU and GCC both code for the amino acid alanine. State the term used to describe this property of the genetic code and explain what it means.2 marks
During translation in a pancreatic cell, a ribosome moves along an mRNA molecule with the base sequence AUG UUC GGA CAU UGA. The codon UGA is a stop codon.
Explain how tRNA molecules make sure that the correct amino acid is added at each codon of the mRNA.2 marks
RNA polymerase transcribes a gene in the nucleus of a cell. A section of the DNA template (antisense) strand has the base sequence TACCAGTTCACT.
Deduce the base sequence of the mRNA transcribed from this section, and describe the role of RNA polymerase in forming it.3 marks

Written by the Exaim team, led by Shaun Daswani (Head of Upper Secondary, Improve ME Institute; MSc Financial Mathematics, Imperial College London; BSc, UCL) and Jason Daswani (operational lead, Improve ME Institute; LSE).