DP IB Biology: HL

Topic Questions

IBBiology: HLDPTopic Questions7. Nucleic Acids (HL Only)7.3 Translation

Syllabus Edition

First teaching 2014

Last exams 2024

|

7.3 Translation

DownloadView
Easy
Medium
Hard
Easy
Medium
Hard
1
Sme Calculator1 mark

Which of the following will lead to the termination of translation?

  • Once the ribosome disassembles into the large and small subunit

  • When the ribosome encounters a stop codon

  • Releasing the free polypeptide from the last tRNA molecule

  • When the ribosome detaches from the mRNA molecule

Choose your answer

Did this page help you?

2
Sme Calculator1 mark

The diagram below shows the structure of a tRNA molecule.7-3_q2

Which of the following correctly identifies the different parts of the tRNA molecule?

  1 2 3 4
A. Amino acid binding site Hydrogen bonds Anticodon Sugar-phosphate backbone
B. Amino acids Hydrogen bonds Anticodon Covalent bonds
C. Amino acid binding site Covalent bonds Anticodon Sugar-phosphate backbone
D. Amino acids Hydrogen bonds Codon Covalent bonds

Choose your answer

Did this page help you?

3
Sme Calculator1 mark

Which of the following is involved in the secondary structure of a protein?

  1. Double helix
  2. β-pleated sheets
  3. Hydrogen bonds
  4. Hydrophobic interactions

  • I. and II. 

  • II. and III.

  • I., II. and III. 

  • II., III. and IV.

Choose your answer

Did this page help you?

4
Sme Calculator1 mark

Which of the following would apply to the polysomes of prokaryotes?

  • Polysomes, containing 80S ribosomes, will appear on the growing mRNA strand along the DNA molecule

  • Polysomes, containing 70S ribosomes, will appear on the growing mRNA strand in the absence of DNA

  • Polysomes, containing 80S ribosomes, will appear on the growing mRNA strand in the absence of DNA

  • Polysomes, containing 70S ribosomes, will appear on the growing mRNA strand along the DNA molecule

Choose your answer

Did this page help you?

5
Sme Calculator1 mark

Bioinformatics involves the use of computers to generate and store large amounts of biological data.

Which of the following would not be an application of bioinformatics?

  • Comparing sequence similarities to determine if an unknown DNA sequence codes for a gene

  • Sequencing DNA to determine protein sequences

  • To determine the rate of aerobic respiration within the mitochondria of an organism

  • Comparing gene sequences between organisms to determine how closely related they are

Choose your answer

Did this page help you?

1
Sme Calculator1 mark

Which of the following enables tRNA activating enzymes to link an amino acid to a tRNA molecule?

  • The tertiary structure of the enzyme active site creates a complementary shape to both tRNA molecule and amino acid which allows them to bind together

  • The tertiary structure of the enzyme active site creates a shape that is similar to both tRNA molecule and amino acid to allow the them to bind together

  • The quaternary structure of the enzyme active site creates a shape that is complementary to the tRNA molecule in order for the amino acid to bind to the attachment site of tRNA

  • The tertiary structure of the specific tRNA molecule creates a shape that is complementary to the active site of the enzyme and also allows the amino acid to bind to its attachment site

Choose your answer

Did this page help you?

2
Sme Calculator1 mark

Which of the following applies to both free and bound ribosomes?

  1. They produce polypeptides that are destined to be used for processes occurring in the cytosol
  2. Translation is interrupted and then re-initiated once movement of the ribosome is complete
  3. They are found in all eukaryotic cells and may be either 70S or 80S
  4. They facilitate the binding of mRNA and tRNA and catalyse the formation of peptide bonds
  5. They have four binding sites to allow the molecules involved with translation to attach to its subunits

  • III. and IV. only

  • IV. and V. only

  • I., III. and IV.

  • II., IV. and V.

Choose your answer

Did this page help you?

3
Sme Calculator1 mark

Ustilago maydis is a fungal pathogen affecting maize. It secretes toxins, known as killer toxins, with the best-characterised one being the KP6 toxin. This particular toxin consists of two small polypeptides that are not linked by covalent bonds. The diagram below shows the ribbon structure of one of the polypeptides of the KP6 toxin.7-3_q3h

Which of the following is the most accurate description of the structure of this polypeptide?

  • This polypeptide represents the tertiary structure of a protein due to the hydrogen bonds that form between the carboxyl group of one R-group and the amino group of another amino acid

  • This polypeptide represents the secondary structure of a protein due to the presence of hydrogen bonds that forms triple-helices and β-pleated sheets

  • This polypeptide represents the quaternary structure of a protein due to the existence of more than one chain that can fit together to form the toxin

  • This polypeptide represents the secondary structure of a protein due to the presence of hydrogen bonds that forms α-helices and β-pleated sheets

Choose your answer

Did this page help you?

4
Sme Calculator1 mark

Leucine is an essential amino acid (EAA) that plays an important role in initiating the process of translation. Scientists investigated the effect of leucine on the process of protein synthesis and protein breakdown in muscles. Participants of the study were divided into three equal groups. Each group were given the same diet that was supplemented with different amounts of leucine (High, low and no added leucine) and the rate of protein synthesis and protein breakdown were monitored over time.

The diagram below shows the results of this study.7-3_q4h

Which of the following provides the most plausible conclusion that can be drawn from the data?

  • Leucine led to a significant increase in protein synthesis while it also increased the rate of protein breakdown in the muscles

  • Low levels of leucine cause a significant increase in protein synthesis with no significant impact on the breakdown of protein in the muscles

  • Supplementing the diet with high levels of leucine will lead to protein being broken down at a higher rate than it is being synthesised in the muscles

  • A diet with no added leucine will have a negative impact on protein synthesis and may result in developing a protein deficiency

Choose your answer

Did this page help you?

5
Sme Calculator1 mark

The following steps describes the events taking place during the elongation of a polypeptide in no particular order.

  1. Free tRNA molecules bind to their corresponding amino acids due to their specific anticodon and transport it to the ribosome 
  2. A tRNA with a complementary anticodon binds to the "A" site bringing its specific amino acid along
  3. The initiator tRNA moves from the "P" to the "E" site on the ribosome where it initiates translation
  4. The amino acid carried by the tRNA at the "P" site is linked to the polypeptide chain by a peptide bond
  5. tRNA carrying the peptide chain moves from the "A" site to the "P" site as the ribosome moves in the 5' → 3' direction along the mRNA molecule

Which of these steps contain incorrect information?

  • I., III. and V.

  • II., III. and V.

  • I., III. and IV.

  • I., III., IV. and V.

Choose your answer

Did this page help you?

11 mark

What is the correct sequence of events during the initiation stage of translation in eukaryotes?

  1. Small subunit of the ribosome binds to the 5’ end of mRNA
  2. Large ribosomal subunit binds to form the ribosome complex
  3. The ribosomal subunit moves along the mRNA until it locates a start codon
  4. An initiator tRNA binds
  5. Elongation of the polypeptide chain can begin                                                                                                                                  
     

    first

    →

    →

    →

    last
    A

    I

    II

    III

    V

    IV
    B

    II

    I

    IV

    III

    V
    C

    I

    II

    III

    IV

    V
    D

    I

    IV

    III

    II

    V

Choose your answer

Did this page help you?

21 mark

Which of the following is not a function of tRNA?

  • Helps translate anticodons into amino acids

  • Peptide bond formation linking amino acid to a polypeptide chain

  • Carrying a specific amino acid to the ribosome

  • Recognising codons on mRNA

Choose your answer

Did this page help you?

31 mark

During the elongation stage of translation the ribosome ‘translocates’ along the mRNA moving in a 5’ → 3’ direction.

What is the immediate effect of this directional movement?

  • The tRNA occupying the P site moves to the A site

  • The E site becomes free

  • The tRNA occupying the A site moves to the P site

  • The polypeptide chain is released from the ribosome

Choose your answer

Did this page help you?

41 mark

Which statements best describe ribosomes?

I.

They are composed of protein and ribosomal RNA

II.

They are found in both eukaryotes and prokaryotes

III.

Ribosomal RNA provides structure

IV.

They consist of two equal-sized subunits

  • I only

  • I and II

  • I, II and III

  • I, II and IV

Choose your answer

Did this page help you?

51 mark

In eukaryotic cells, ribosomes can be either free or bound.

Which of the following proteins would most likely be synthesised by bound ribosomes?

  • Mitochondrial outer membrane protein

  • Glyceraldehyde 3-phosphate dehydrogenase involved in glycolysis

  • Lysosomal acid lipase

  • Histone protein

Choose your answer

Did this page help you?

61 mark

In prokaryotes, the processes of transcription and translation are said to be coupled, which means they can proceed simultaneously.

Which is the key cellular feature of prokaryotes that allows this to happen?

  • Circular chromosomal DNA

  • Free ribosomes

  • The lack of a nucleus

  • The presence of introns in prokaryotic DNA

Choose your answer

Did this page help you?

71 mark

The bacterium Staphylococcus aureus (S. aureus) is one of the main human pathogens and can cause many serious infectious diseases. Mutations in the mec A gene has allowed S.aureus to become resistant to many antibiotics. The table below shows a (Clustal W) partial nucleotide sequence alignment of mec A for different isolates of S. aureus. The drug resistant strain has a base substitution mutation (shown in bold) which changes the amino acid residue from serine to threonine.

S. aureus isolate 1

AAC GGA ACC GGT AAG GAC GCG ATC ACC AGC

S. aureus isolate 2

AAC GGA ACC GGT AAG GAC GCG ATC ACC AGC

S. aureus isolate 3

AAC GGA ACC GGT AAG GAC GCG ATC ACC AGC

Drug resistant strain

AAC GGA ACC GGT AAG GAC GCG ATC ACC ACC

Which of the following statements most likely explains how an amino acid change can cause antibiotic resistance?

  • Alteration of the drug target site which prevents binding

  • Prevents the bacterial cell from synthesising the target protein

  • Bacteria produce less of the target protein 

  • Can introduce a stop codon

Choose your answer

Did this page help you?

81 mark

Which interactions or features differentiate tertiary structure from secondary structure in proteins?

  1. Hydrogen bonds
  2. Disulphide bridges
  3. Hydrophobic interactions
  4. Alpha-helices
  5. Interactions between R-groups of amino acids

  • I and II

  • II and V

  • II, III and IV 

  • II, III and V

Choose your answer

Did this page help you?

91 mark

Which of the following best describes the quaternary structure of proteins?

  • The three-dimensional structure of a polypeptide chain

  • Arrangement of beta-pleated sheets

  • The linear sequence of amino acids

  • How polypeptide chains are arranged

Choose your answer

Did this page help you?

101 mark

The diagram below represents an electron micrograph of eukaryotic polysomes.

q10_7-3_translation_ib_biology_hl_mcq                      

What is the main advantage that polysomes give to a eukaryotic cell?

  • Translation can be initiated before transcription is complete

  • Allows very long mRNA molecules to be translated

  • They increase the overall rate of translation

  • Allows structurally different polypeptides to be produced from the same mRNA

Choose your answer

Did this page help you?