- Specification route
- 3.4.2
- Question bank
- 20 questions
- Course stage
- AS / Year 12
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20 standard questions. No sign-in required.
Practise Biology maths and data skills
Sessions use up to the requested number of available questions. Standard practice uses levels 1–5.
Sample questions
How is the concept of a cell's 'proteome' defined?
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It is the protein equivalent of the genome.
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Answer: The full range of proteins that a cell is able to produce.
The concept of the genome as the complete set of genes in a cell and of the proteome as the full range of proteins that a cell is able to produce.
What is the key difference in the transcription process between prokaryotes and eukaryotes?
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Eukaryotic genes contain non-coding introns that must be removed before translation.
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Answer: In eukaryotes, transcription produces pre-mRNA which is spliced to form mRNA, whereas in prokaryotes it directly produces mRNA.
In prokaryotes, transcription results directly in the production of mRNA from DNA. In eukaryotes, transcription results in the production of pre-mRNA; this is then spliced to form mRNA.
During transcription, which enzyme is responsible for joining mRNA nucleotides together?
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This enzyme builds the polymer of RNA.
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Answer: RNA polymerase
Transcription as the production of mRNA from DNA. The role of RNA polymerase in joining mRNA nucleotides.
Translation is the production of polypeptides. Which three components play a direct role in this process at the ribosome?
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The process requires an energy source, a reading site, and a molecule to bring the amino acids.
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Answer: Ribosomes, tRNA and ATP
Translation as the production of polypeptides from the sequence of codons carried by mRNA. The roles of ribosomes, tRNA and ATP. ATP is required to attach amino acids to tRNA.
A pre-mRNA molecule in a eukaryotic cell contains $450$ nucleotides. After splicing, the mature mRNA contains $300$ nucleotides. What do the removed $150$ nucleotides represent?
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Splicing removes parts of the gene that do not code for amino acids.
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Answer: Introns, which are non-coding sequences.
In eukaryotes, transcription results in the production of pre-mRNA; this is then spliced to form mRNA. Within genes, exons code for amino acid sequences and are separated by non-coding sequences called introns. Introns are removed during splicing.
If a drug specifically inhibits the action of RNA polymerase in a eukaryotic cell, which process will be immediately halted?
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Look at the name of the enzyme: it synthesizes an RNA polymer.
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Answer: The transcription of DNA into pre-mRNA.
Transcription as the production of mRNA from DNA. The role of RNA polymerase in joining mRNA nucleotides. Blocking it stops transcription.
How does the structure of a tRNA molecule compare to that of an mRNA molecule?
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tRNA has an anticodon and an amino-acid attachment site, so its single strand folds into a specific structure.
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Answer: tRNA is a single strand folded by intramolecular hydrogen bonding and has an anticodon plus an amino-acid attachment site, while mRNA is a relatively linear single strand carrying codons.
mRNA is a relatively linear single-stranded molecule carrying a sequence of codons. tRNA is a single strand folded by intramolecular hydrogen bonding; it has an anticodon and an amino-acid attachment site.
A strand of DNA has the base sequence $TAC\ GGA\ CTC$. What will be the corresponding sequence of anticodons on the tRNA molecules during translation?
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DNA translates to mRNA (complementary). mRNA pairs with tRNA anticodons (complementary again). This means tRNA matches the DNA template, but with U instead of T.
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Answer: $UAC\ GGA\ CUC$
DNA ($TAC\ GGA\ CTC$) transcribes to mRNA ($AUG\ CCU\ GAG$). The tRNA anticodons pair with mRNA, returning to the original DNA sequence but substituting Uracil for Thymine ($UAC\ GGA\ CUC$).
Practise this topic
20 standard questions are available (levels 1–5). No sign-in required.