IBBiologyHLExam QuestionsUnity & DiversityCell Structure

Syllabus Edition

First teaching 2023

First exams 2025

|

Cell Structure (HL IB Biology)

Exam Questions

3 hours55 questions

Select a question set to download for
Cell Structure

Select an answer set to view for
Cell Structure

Easy
Medium
Hard
1
Sme Calculator1 mark

The electron micrograph below shows a plant cell. 

The scale bar (measuring 45 mm in length) on this drawing represents a length of 10 μm.

e-q2

Which of the following correctly identifies the magnification at which the micrograph is viewed?

  • x45000

  • x4.5

  • x4500

  • x450

Choose your answer

Did this page help you?

21 mark

Which changes can occur when a cell differentiates from a stem cell into a specialised cell?

   I. The size of the cell can change

   II. The number and type of proteins in the cell changes

   III. Enzymes cut out the DNA that is no longer needed 

  • I and II only

  • II and III only

  • I and III only

  • I, II and III

Choose your answer

Did this page help you?

31 mark

Which row correctly compares the magnification and resolution of an electron microscope with a light microscope?

  Magnification Resolution
A. Lower Higher
B. Higher Lower
C. Higher Higher
D. Lower Lower

    Choose your answer

    Did this page help you?

    41 mark

    The diagram shows a bacterium.

    1-2-e-q2-paper-1

    Which three structures are found in both an animal cell and this bacterial cell?

    • Cell membrane, cell wall and DNA

    • Cell membrane, DNA and ribosome

    • Capsule, DNA and ribosome

    • Capsule, cell membrane and cell wall

    Choose your answer

    Did this page help you?

    51 mark

    Which of the following can not be viewed using a light microscope?

    • Nucleus

    • Cell wall

    • Chloroplasts

    • Ribosomes

    Choose your answer

    Did this page help you?

    61 mark

    The table shows some possible units for measuring alveoli, white blood cells and cell walls.

    Which of the rows show the most suitable units for measuring each of these structures?

      Diameter of alveoli Diameter of white blood cells Width of cell walls
    A. mm µm µm
    B. mm µm nm
    C. µm nm µm
    D. µm µm nm

      Choose your answer

      Did this page help you?

      71 mark

      The diagram shows a typical plant cell.

      q7-1-2-cells-origin-medium-ib-hl-biology

      Which of the cell components would be present in prokaryotes?

      • I only

      • II only

      • II and III

      • I and IV

      Choose your answer

      Did this page help you?

      81 mark

      Which row correctly describes the features of prokaryotic chromosomal DNA?

      A. Associated with histone proteins Circular
      B. Not associated with histone proteins Linear
      C. Not associated with histone proteins Circular
      D. Contains a few hundred genes  Circular

        Choose your answer

        Did this page help you?

        11 mark

        A prokaryotic cell has a diameter of 1 µm. The cell is magnified ×50 000 by an electron microscope.

        In the electron micrograph that is produced by the electron microscope, what is the diameter of the prokaryotic cell?

        • 5 x 100 mm

        • 5 x 10-1 mm

        • 5 x 102 mm

        • 5 x 101 mm

        Choose your answer

        Did this page help you?

        21 mark

        The electron micrograph shows the organelles in a leaf cell. A student uses their ruler to measure the length of the scale bar, which they find to be 1.5 cm.

        q1-1-1-cells-theory-medium-ib-hl-biology

        What is the magnification of the micrograph?

        • ×7000

        • ×7.5

        • ×3000

        • ×300

        Choose your answer

        Did this page help you?

        31 mark

        The electron micrograph below shows a root vascular system. The magnification of the image is ×200. A student uses a ruler to measure distance X and finds it to be 10 mm.

        q2-1-1-cells-theory-medium-ib-hl-biology

        What is the diameter of the cell labelled Y?

        • 100 µm

        • 50 µm

        • 10 µm

        • 5 µm

        Choose your answer

        Did this page help you?

        41 mark

        The electron micrograph of the plant cell has a 2 cm scale line labelled 5 µm.

        q4-1-1-cells-theory-medium-ib-hl-biology

        What is the magnification?

        • ×5000

        • ×4000

        • ×2000

        • ×1000  

        Choose your answer

        Did this page help you?

        51 mark

        Erythrocytes (red blood cells) have a diameter of 7 000 nm. Pancreatic cells have a diameter of 35 µm.

        Which of these statements about the relative sizes of these cells is correct?

        • The erythrocytes are 5 times smaller

        • The erythrocytes are 50 times smaller

        • The erythrocytes are 5 times larger

        • The erythrocytes are 50 times larger

        Choose your answer

        Did this page help you?

        61 mark

        Which of the following ideas are part of cell theory?

        1. Cells are the smallest unit of life
        2. Cells show great variety in shape and structure
        3. Cells are derived from other cells (pre-existing cells) by division

        • I only

        • II only

        • I and III only

        • II and III only

        Choose your answer

        Did this page help you?

        71 mark

        The role of exocrine gland cells in the pancreas is to secrete digestive enzymes into the pancreatic duct. 

        Which of the following organelles does not directly help it to achieve this task? 

        • Rough endoplasmic reticulum

        • Golgi apparatus

        • Lysosomes

        • Mitochondria

        Choose your answer

        Did this page help you?

        81 mark

        Which of the following is not a correct description of a light microscope or an electron microscope?

        • An electron microscope can resolve specimens as small as 0.5 nm in diameter

        • A light microscope has a maximum resolution of 0.2 µm

        • An electron microscope has a maximum resolution of 0.05 nm

        • A light microscope can resolve specimens as small as 200 nm in diameter

        Choose your answer

        Did this page help you?

        91 mark

        The list below contains structures that are all features of eukaryotic cells.

        1. Nucleus
        2. Endoplasmic reticulum
        3. Lysosome
        4. Chloroplast
        5. Mitochondrion

        Which of these structures contain(s) a double membrane?

        • I, II and III

        • I, III and IV

        • I, IV and V

        • II, III and IV

        Choose your answer

        Did this page help you?

        101 mark

        Which set of observations would indicate that a student is observing a eukaryotic cell?

          Cytoplasm contains endoplasmic reticulum Protein molecules are associated with the DNA Diameter <1 µm
        A X ✓ X
        B X X ✓
        C ✓ ✓ X
        D ✓ X X

          Choose your answer

          Did this page help you?

          111 mark

          Which of the following is evidence for the endosymbiotic theory?

          • 70S ribosomes can be found in prokaryotic cells

          • Mitochondria contain their own DNA

          • Meteorites have been found that contain organic molecules

          • In certain cases, gene transfer from prokaryotic cells to eukaryotic cells via plasmids has been found to occur

          Choose your answer

          Did this page help you?

          121 mark

          The image below shows an electron micrograph of a specialised cell.

          e-4

          Which of the following correctly identifies the function of this specialised cell?

          • This is a cell found in a gland that secretes enzymes for digestion

          • This is a cell that carries out photosynthesis in the leaf of a plant

          • This is a cell that transports oxygen around the body in the blood

          • This is a cell that absorbs nutrients from digested food and transports them into the small intestine

          Choose your answer

          Did this page help you?

          131 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?

          141 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?

          151 mark

          John Cairns carried out a study in which he kept E. coli bacteria in a solution containing radioactive thymine. 

          What was he able to conclude from the results of his study?

          • Prokaryotes have a circular chromosome.

          • E. coli have a circular chromosome.

          • Autoradiography does not produce clear enough results to determine whether bacteria have one chromosome or many.

          • Bacteria replicate their DNA using a structure called a replication fork.

          Choose your answer

          Did this page help you?

          161 mark

          Which of the following statements about eukaryotic chromosomes are correct? 

          1. Chromosomes are long, linear molecules that can be condensed for compact storage.
          2. After DNA replication, the two strands of DNA are held together at the centromere.
          3. DNA wraps around histone proteins to form chromatids.

          • I and II only

          • II only

          • II and III only

          • I, II, and III

          Choose your answer

          Did this page help you?

          1
          Sme Calculator          1 mark

          A stage micrometer with small divisions of 0.1 mm was used to calibrate an eyepiece graticule, as shown in the diagram below.

          h-q1

           A slide containing a plant cell was placed on the stage in place of the stage micrometer. 

          What is the width of one of the chloroplasts below?

          plant-cell-with-graticule

          • 100 µm

          • 50 µm

          • 10 µm

          • 0.5 mm

          Choose your answer

          Did this page help you?

          21 mark

          A giant bacterium, Epulopiscium fishelsoni was discovered in 1985.

          Which cell structure(s) would enable biologists to classify Epulopiscium as prokaryotic?

          • Circular DNA and 70S ribosomes occurring freely in the cytoplasm, and a cell wall made of murein

          • A pair of centrioles close to a nuclear pore, and 70S and 80S ribosomes occurring freely in the cytoplasm

          • Smooth endoplasmic reticulum throughout the cytoplasm, and a cell wall made of murein

          • A cellulose cell wall outside the plasma membrane, 70S ribosomes, and circular DNA occurring freely in the cytoplasm

          Choose your answer

          Did this page help you?

          31 mark

          A cell which is actively growing is supplied with radioactive amino acids.

          Which cell component will show an increase in radioactivity first?

          • Mitochondria

          • Golgi apparatus

          • Rough endoplasmic reticulum

          • Nucleus

          Choose your answer

          Did this page help you?

          41 mark

          The image below is an electron micrograph of part of an animal cell.

          Which of the following options (A to D) would be the site of protein modification and packaging?

          h-3

            Choose your answer

            Did this page help you?

            51 mark

            The electron micrograph below shows a small section of a palisade mesophyll cell.

            q1-1-2-cells-origin-medium-ib-hl-biology

            Which structure controls the exchange of substances into and out of the cell?

              Choose your answer

              Did this page help you?