Translation (Part 1)

Which statement BEST explains why translation requires adaptor molecules?
A. Amino acids directly base pair with mRNA codons
B. There is no chemical affinity between amino acids and nucleotides
C. Ribosomes cannot recognize mRNA without adaptors
D. Amino acids are too large to interact with nucleotides

B

The primary energetic cost of translation is due to:
A. Ribosome assembly
B. tRNA synthesis
C. Amino acid activation and peptide bond formation
D. mRNA degradation

Which feature MOST strongly influences translation efficiency in prokaryotes?
A. Presence of a poly-A tail
B. Kozak sequence strength
C. Complementarity of Shine-Dalgarno sequence to rRNA
D. Length of the ORF

A mutation disrupts the Shine-Dalgarno sequence. What is the MOST likely outcome?
A. Incorrect amino acid incorporation
B. Reduced ribosome binding and translation initiation
C. Premature termination
D. Increased translation rate

Which of the following correctly compares prokaryotic and eukaryotic translation?
A. Both use Kozak sequences
B. Only eukaryotes have polycistronic mRNA
C. Prokaryotes can couple transcription and translation
D. Eukaryotes translate faster than prokaryotes

What is the key role of aminoacyl-tRNA synthetases?
A. Form peptide bonds
B. Match codons with amino acids directly
C. Charge tRNAs with correct amino acids
D. Bind ribosomal subunits

Why is the “editing pocket” essential in aminoacyl-tRNA synthetases?
A. It speeds up peptide bond formation
B. It ensures correct mRNA binding
C. It removes incorrectly attached amino acids
D. It stabilizes ribosomes

Which structure of tRNA is MOST critical for synthetase recognition?
A. Variable loop
B. ψU loop
C. Acceptor stem
D. D loop

A ribosome continues translation immediately after finishing an upstream ORF without binding a new RBS. This is an example of:
A. Scanning
B. Translational coupling
C. Termination
D. Wobble pairing

Why can a single tRNA synthetase recognize multiple tRNAs?
A. All tRNAs have identical sequences
B. Codon redundancy requires isoaccepting tRNAs
C. Ribosomes enforce specificity
D. tRNAs differ only in length

Translation converts __________ into an amino acid sequence.

The three-nucleotide sequence on mRNA is called a __________.

The ribosome binding site in prokaryotes is called the __________ sequence.

The initiator codon in eukaryotes is __________.

tRNAs contain a __________ at their 3′ end for amino acid attachment.

A tRNA carrying an amino acid is called a __________ tRNA.

The enzyme that attaches amino acids to tRNAs is called __________.

The energy for peptide bond formation comes from the __________ bond.

The “second genetic code” refers to __________.

In eukaryotes, ribosomes locate the start codon via __________.

Amino acids directly base pair with mRNA codons. (True/False)

Translation uses the majority of a cell’s energy. (True/False)

All organisms have exactly 20 aminoacyl-tRNA synthetases. (True/False)

The ribosome ensures that the correct amino acid is attached to tRNA. (True/False)

A single mRNA in eukaryotes typically encodes multiple proteins. (True/False)

Modified bases in tRNA are essential for survival. (True/False)

Start codons define the reading frame. (True/False)

Prokaryotic translation is slower than eukaryotic translation. (True/False)

The anticodon loop directly interacts with mRNA codons. (True/False)

Misacylation occurs frequently in cells. (True/False)

Match the term to its function:

Column A	Column B
1. Shine-Dalgarno sequence	A. Peptide bond catalysis
2. Ribosome	B. Amino acid attachment site
3. Acceptor stem	C. Prokaryotic RBS
4. Anticodon loop	D. Codon recognition
5. Aminoacyl-tRNA synthetase	E. Charges tRNA

Match the feature to organism type:

Column A	Column B
1. Kozak sequence	A. Prokaryotes
2. Polycistronic mRNA	B. Eukaryotes
3. Coupled transcription/translation	C. Both
4. Poly-A tail	D. Eukaryotes
5. Shine-Dalgarno	A. Prokaryotes

Explain why translation requires tRNA as an adaptor rather than direct interaction between amino acids and mRNA.

Describe TWO mechanisms by which aminoacyl-tRNA synthetases ensure high fidelity.

Compare translational initiation in prokaryotes vs eukaryotes.

Explain how translational coupling increases efficiency in prokaryotes.

Why is the ribosome described as “blind” in translation? What are the implications?

Explain how mutations in the acceptor stem of tRNA could alter protein synthesis.

Describe the structural features of tRNA that allow it to function effectively.

Why is charging of tRNA considered an energy-rich process?

Explain the concept of the “second genetic code.

Predict the effect of removing the poly-A tail from a eukaryotic mRN