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BUILD A PROCESS

Build a withdrawal reflex

Place a spinal reflex pathway in functional order.

Build a process

Use the up and down buttons to build the sequence, then check your reasoning. Some biological events overlap; follow the simplified pathway described here.

  1. 1
    Skeletal muscle contracts
  2. 2
    Motor neuron carries output
  3. 3
    Spinal interneuron relays the signal
  4. 4
    Sensory neuron conducts towards the spinal cord
  5. 5
    Receptor detects a harmful stimulus
Read the complete pathway
  1. Receptor detects a harmful stimulus. Transduction changes the stimulus into electrical activity.
  2. Sensory neuron conducts towards the spinal cord. This is the afferent pathway.
  3. Spinal interneuron relays the signal. Withdrawal is a polysynaptic reflex.
  4. Motor neuron carries output. This is the efferent pathway.
  5. Skeletal muscle contracts. The effector withdraws the body part.

Explain what you observed

Does every reflex require an interneuron?

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Your study notes

Take the next step

Connect this activity with your lesson notes and chapter practice.

Read a related learning guide →Practise Coordination & Control →Open the student notes folder ↗

Concepts and sources

Curriculum connections: 5.4, 5.5. Selected concepts.

Read the supporting source ↗PMDC curriculum ↗

Questions and explanations are original teaching material; these are not official exam questions.

Keep exploring Coordination & Control

Model

Explore an action potential

Scrub a voltage trace and inspect sodium and potassium channel states.

Sort & explain

Trace information through a neuron

Match structure to reception, conduction and output.

Sort & explain

Match stimulus to receptor

Treat receptors as biological transducers.