Structure of a neuron
Dendrites → cell body → axon → axon endings; synapse to next cell.
Step 1 — Study the figure
Cover the label key on the image, name each numbered part, then check the explanations below.
Step 2 — Diagram details for students
What this diagram shows
A neuron carries information as an electrical impulse and passes it chemically across a synapse. Dendrites receive, axon transmits, and endings release messenger chemicals. This structure is the basis of nervous control in animals.
Numbered parts — mark & remember
Match each number on the figure with the meaning below. Say the function aloud once.
1 Dendrites
Dendrites are branched endings that receive signals from receptors or other neurons. They pass the message toward the cell body. More branching allows richer input connections.
2 Cell body
The cell body contains the nucleus and maintains the neuron. It processes incoming signals before sending an impulse along the axon. Damage to cell bodies can permanently harm neural pathways.
3 Axon
The axon is a long fibre that carries the electrical impulse away from the cell body. Many axons are long so signals travel quickly to distant effectors. Direction is one way: cell body toward axon endings.
4 Axon endings
At the endings, the electrical message causes release of chemical messengers. These chemicals cross the synapse to the next cell. This converts electrical signal into chemical signal temporarily.
5 Synapse
A synapse is the gap between two neurons (or neuron and effector). The impulse does not jump as electricity across the gap. Chemicals diffuse across and start a new impulse in the next neuron.
How to read this figure
- Follow the path: dendrite → cell body → axon → ending → synapse.
- Remember electrical along fibre, chemical at synapse.
- Impulse direction is unidirectional at synapses.
Redraw for board marks
- Draw cell body with dendrites on one side.
- Add a long axon ending in branches.
- Show a gap labelled synapse before the next neuron.
Board answer tip: Draw a labelled neuron and write one line each for dendrite, axon, and synapse function.
Exam tips — don’t lose marks
- Do not write that electricity jumps the synapse.
- Name receptor → neuron → effector in reflex answers.
- Synapse chemicals are why direction is one-way.