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How are plant and animal cells alike, and how do they differ?

Compare the structure of typical plant and animal cells and relate specialised cells to their functions

A focused answer to the O-Level Biology outcome on comparing plant and animal cells. Shared and unique structures, a clear comparison table in words, and how specialised cells are adapted to their functions.

Generated by Claude Opus 4.88 min answer

Reviewed by: AI editorial process; not yet individually human-reviewed

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  1. What this dot point is asking
  2. The answer
  3. Examples in context
  4. Try this

What this dot point is asking

SEAB wants you to compare a typical plant cell with a typical animal cell, stating clearly which structures they share and which belong to plant cells only. You should also be able to describe how some specialised cells are adapted, in structure, to carry out a particular function. The skill being tested is organised comparison, not just a list.

The answer

Structures shared by plant and animal cells

Both plant and animal cells have a cell surface membrane (controls entry and exit of substances), cytoplasm (where reactions happen), a nucleus (controls the cell and holds DNA), and mitochondria (release energy in respiration).

Structures found only in plant cells

A typical plant cell also has three extra features:

  • A cell wall made of cellulose, giving shape and support.
  • Chloroplasts containing chlorophyll, for photosynthesis.
  • A large permanent vacuole filled with cell sap, which keeps the cell firm.

A typical animal cell has none of these as permanent features, although it may have small temporary vacuoles.

The comparison in words

Reading down the list: both have a membrane, cytoplasm, nucleus and mitochondria. Only the plant cell has a cell wall, chloroplasts and a large vacuole. The plant cell therefore tends to have a fixed, regular shape, while the animal cell, without a wall, has a more rounded or irregular shape.

Specialised cells

Most cells are specialised, meaning their structure is adapted to a particular function. Examples include:

  • Red blood cell: no nucleus and a biconcave shape, to carry more oxygen.
  • Root hair cell: a long extension to increase surface area for absorbing water.
  • Nerve cell (neurone): long and thin to carry electrical impulses over a distance.
  • Sperm cell: a tail (flagellum) for swimming and many mitochondria for energy.

Examples in context

Example 1. Comparing under the microscope. Looking at onion epidermis and cheek cells side by side, the onion cells show clear box-like walls and the cheek cells show only thin rounded membranes. This visible difference is the cell wall in action.

Example 2. The sperm and the egg. A sperm cell is tiny, with a tail and many mitochondria for swimming; an egg cell is large, with food stores. Comparing them shows how two cells of the same organism can be specialised in very different ways.

Try this

Q1. Name two structures found in both plant and animal cells. [2 marks]

  • Cue. Any two of: cell surface membrane, cytoplasm, nucleus, mitochondria.

Q2. Explain why a plant cell keeps a fixed shape while an animal cell does not. [2 marks]

  • Cue. A plant cell has a rigid cellulose cell wall that holds its shape; an animal cell has no cell wall, so it is more rounded and changeable.

Q3. Describe one way a root hair cell is adapted to absorb water. [2 marks]

  • Cue. It has a long thin extension that increases its surface area, so water can be absorbed faster by osmosis from the soil.

Exam-style practice questions

Practice questions written in the style of SEAB exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.

Original4 marksA student examines a cell and a leaf cell under the microscope. State two structures present in both cells and two structures present only in the leaf cell.
Show worked answer →

Structures present in both: any two of cell surface membrane, cytoplasm, nucleus, mitochondria.

Structures present only in the leaf (plant) cell: any two of cell wall, chloroplasts, large permanent vacuole.

Markers reward two correct shared features and two correct plant-only features. Listing a cell wall as a shared feature, or a nucleus as plant-only, scores no mark because the comparison is wrong.

Original5 marksDescribe how a red blood cell and a root hair cell are each adapted to their functions.
Show worked answer →

A red blood cell carries oxygen. It has no nucleus, which leaves more room for haemoglobin; it is a biconcave disc, which gives it a large surface area to volume ratio for faster oxygen uptake and release; and it is small and flexible to squeeze through narrow capillaries.

A root hair cell absorbs water and mineral ions from the soil. It has a long thin extension (the root hair) that greatly increases its surface area for absorption, and a thin cell wall so water can enter quickly by osmosis.

Markers reward at least two clear adaptations for each cell, each linked to its function rather than just described.

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