Difference Between Plant and Animal Cell — Complete Comparison

Question

List and explain the key differences between plant and animal cells. Which structures are present in plant cells but absent in animal cells, and vice versa? Use a comparison table.

Solution — Step by Step

Step 1: Understand the Common Ground First

Before we list differences, remember what plant and animal cells share — because both are eukaryotic:

• Nucleus (membrane-bound)
• Cell membrane (plasma membrane)
• Cytoplasm
• Mitochondria
• Ribosomes (80S in cytoplasm)
• Endoplasmic reticulum
• Golgi apparatus
• Lysosomes (more prominent in animal cells)

The differences arise because plants have additional requirements: they make their own food (photosynthesis) and need mechanical support without a skeleton.

Step 2: The Key Differences

1. Cell Wall

• Plant cell: Has a rigid cell wall made of cellulose outside the cell membrane. Provides structural support and shape.
• Animal cell: No cell wall. Only the flexible cell membrane acts as the outer boundary.

This is why plant cells have a fixed, regular shape; animal cells have irregular, changeable shapes.

2. Chloroplasts

• Plant cell: Present (in green photosynthetic cells). Contains chlorophyll. Site of photosynthesis.
• Animal cell: Absent. Animals cannot make their own food — they must consume it.

3. Central Vacuole

• Plant cell: Large central vacuole (may occupy 90% of cell volume in mature cells). Bounded by the tonoplast membrane. Contains cell sap. Maintains turgor pressure.
• Animal cell: No large central vacuole. May have small, temporary food vacuoles or contractile vacuoles, but nothing like the plant central vacuole.

4. Centrioles

• Plant cell: Absent (in higher/flowering plants — angiosperms). Lower plants (mosses, ferns) do have centrioles.
• Animal cell: Present. Located in the centrosome. Essential for forming the mitotic spindle during cell division.

5. Plasmodesmata

• Plant cell: Present. Thin cytoplasmic channels that pass through the cell walls between adjacent plant cells. Allow communication and transport between cells.
• Animal cell: Absent. Animal cells communicate through gap junctions instead.

6. Lysosomes

• Plant cell: Rarely seen (vacuole performs some lysosomal functions).
• Animal cell: Abundant. "Suicide bags of the cell" — contain hydrolytic enzymes for intracellular digestion.

Comparison Table

Why This Works — Functional Reasoning

Each structural difference has a functional explanation:

• Cell wall present in plants: Plants can't move away from stress — they need rigidity to stand tall and withstand wind and gravity. No cell wall needed in animals because they have skeletons (internal) and cells can be flexible for movement.

• Chloroplasts only in plants: Photosynthesis is the defining feature of autotrophs. Plants use solar energy directly; animals rely on consuming organic molecules made by plants (or other animals).

• Large vacuole in plants: Turgor pressure from the vacuole pushes outward against the cell wall — this is how non-woody plants stay upright. The vacuole is also a storage compartment for waste products, pigments, and ions.

• Centrioles only in animals: Higher plants assemble their spindle fibres without centrioles, using a different MTOCs (microtubule organising centres). Animal cells depend on centrosomes/centrioles for accurate spindle assembly.

Alternative Method — Drawing and Labelling

The most common CBSE question format is: "Draw a labelled diagram of a plant cell and an animal cell, highlighting the differences."

Key labels for plant cell: cell wall, cell membrane, chloroplast, large central vacuole (with tonoplast), nucleus, mitochondria, ER, Golgi, plasmodesmata.

Key labels for animal cell: cell membrane, centrioles, small vacuoles, nucleus, mitochondria, lysosomes, ER, Golgi.

When drawing, always show the cell wall as a thick outer boundary (plant) vs a single thin line (animal).

Common Mistake