GCSE Biology Cells & cell division questions by topic

The diagram shows a generalised animal cell.

1. (a)Name the structure that controls the cell’s activities.[1]
2. (b)Name the site of aerobic respiration.[1]
3. (c)Name the structure that controls what enters and leaves the cell.[1]

Compare plant cells with bacterial cells.

1. (a)Name two structures found in plant cells but not in animal cells.[2]
2. (b)Explain why bacteria are described as prokaryotic.[1]
3. (c)Name the small rings of DNA found in bacterial cells.[1]

Put the three stages of the cell cycle in order, starting with the growth stage.

1. (a)State what is copied before a cell divides.[1]
2. (b)Describe what happens during mitosis.[1]
3. (c)State how many cells are produced and compare their chromosomes with the parent cell.[1]

A student prepares a slide of onion cells to observe with a light microscope.

1. (a)Explain why the onion layer is stained with iodine.[1]
2. (b)Explain why the cover slip is lowered at an angle.[1]
3. (c)Name the adjustment used to sharpen the image at high power.[1]
4. (d)State one safety precaution for this practical.[1]

A student views onion cells with a ×10 eyepiece lens and a ×4 objective lens. One cell’s image is 8.0 mm wide.

1. (a)Calculate the total magnification.[1]
2. (b)Calculate the real width of the onion cell in millimetres.[1]
3. (c)Give the real width in micrometres.[1]
4. (d)Explain why magnification has no units.[1]

A root hair cell absorbs mineral ions from soil water where the ion concentration is lower inside the root hair than in the surrounding soil particles.

1. (a)Name the process that moves the ions against their concentration gradient.[1]
2. (b)Explain why the root hair cell contains many mitochondria.[2]
3. (c)Name the cells that carry the absorbed ions up the stem in solution.[1]

A bacterium is 3 µm long and a cheek cell is 45 µm long.

1. (a)Give the length of the bacterium in millimetres.[1]
2. (b)Write the bacterium’s length in metres in standard form.[1]
3. (c)Calculate how many times longer the cheek cell is than the bacterium.[1]
4. (d)A ×40 objective is used with a ×10 eyepiece. State the total magnification.[1]

A student draws a chloroplast 12 mm long. The real chloroplast is 6 µm long.

1. (a)Give the drawing length in micrometres.[1]
2. (b)Calculate the magnification of the drawing.[2]
3. (c)Explain why the magnification has no units.[1]
4. (d)Give the real length in nanometres.[1]

Explain how three specialised cells are adapted to their functions.

1. (a)Explain how one feature of a nerve cell helps it carry impulses quickly.[2]
2. (b)Explain why sperm cells contain many mitochondria.[2]
3. (c)Explain why phloem cells have very few sub-cellular structures.[2]

This question is about stem cells.

1. (a)Define a stem cell.[2]
2. (b)State where stem cells are found in adult humans and name the cells they mainly form.[2]
3. (c)Name the plant tissue that can differentiate throughout the plant’s life.[1]
4. (d)Give one use of cloning plants from meristems.[1]

A student examines cheek cells with a ×10 eyepiece and a ×10 objective. One object on the slide has an image width of 12 mm.

1. (a)Calculate the total magnification.[1]
2. (b)Calculate the real width of the object in millimetres.[2]
3. (c)Give the real width in micrometres.[1]
4. (d)Bacterial cells are about 1–2 µm long. Use your answer to (c) to explain whether the object could be a bacterium.[1]

A scientist counts 480 cells in a squash of a plant root tip. In 36 of them, chromosomes are being pulled to opposite ends of the cell.

1. (a)Name the stage of the cell cycle in these 36 cells.[1]
2. (b)Calculate the percentage of cells in this stage.[2]
3. (c)Explain why the DNA must be copied before this stage.[2]
4. (d)Suggest why the root tip was used rather than a mature leaf.[1]

Explain how electron microscopy increased our understanding of sub-cellular structures. (Higher)

1. (a)Compare the magnification of electron and light microscopes.[2]
2. (b)Explain why fine detail such as ribosomes could not be studied with light microscopes.[2]

A scientist observes a root tip. Of 240 cells counted, 60 are in the DNA-replication stage of the cell cycle.

1. (a)Calculate the percentage of cells in the DNA-replication stage.[2]
2. (b)Describe the three overall stages of the cell cycle.[3]
3. (c)Suggest why root tips contain many dividing cells.[1]

The field of view of a microscope is 0.5 mm across. A chain of 25 cells stretched across the field.

1. (a)Calculate the mean length of one cell in millimetres.[2]
2. (b)Give this length in micrometres.[1]
3. (c)The student draws one cell at ×400. Calculate the drawing length in millimetres.[2]
4. (d)State two rules for a good biological drawing.[2]

Explain why daughter cells produced by the cell cycle are genetically identical, and describe two situations in a human where this type of division is occurring.

1. (a)Explain why the two daughter cells are identical.[4]
2. (b)Describe two situations where mitosis is happening.[2]

Discuss the benefits and risks of using embryonic stem cells, including therapeutic cloning, to treat human disease.

1. (a)Write a balanced evaluation. Include benefits, risks and objections, and finish with a conclusion.[6]

Electron microscopes transformed what biologists knew about cells. A typical ribosome is 20 nm across.

1. (a)Explain two ways in which an electron microscope shows more detail than a light microscope.[2]
2. (b)Give the ribosome’s diameter in micrometres.[1]
3. (c)Write the ribosome’s diameter in metres in standard form.[1]
4. (d)Explain one limitation of electron microscopy.[2]