← Back to full paperPrevious questionNext question

Question 5

From Biology SL Paper 2 (November 2024, TZ2)

Grade your answerAnswer this question in practice mode and submit it for feedback.Practice under timed constraintsOpen the paper flow with timed full-exam navigation.
View source PDF page 5
  1. (a) Label the structures X, Y and Z on the diagram of a motor neuron. [3]
Diagram of a motor neuron with parts X, Y, Z indicated for labeling.
Diagram of a motor neuron with parts X, Y, Z indicated for labeling.

The section of the axon between the solid black lines in the motor neuron diagram is enlarged and shown.

Enlarged section of an axon showing charge distribution for resting potential and depolarized parts, to be labeled R and D.
Enlarged section of an axon showing charge distribution for resting potential and depolarized parts, to be labeled R and D.

(b) On the diagram, label the part of the axon representing resting potential with R and the depolarized part with D. [2]

The oscilloscope trace of a stimulated axon is shown.

Graph showing membrane potential on the y-axis and time on the x-axis, with a trace illustrating an action potential.
Graph showing membrane potential on the y-axis and time on the x-axis, with a trace illustrating an action potential.

(c) Annotate the oscilloscope trace to show depolarization. [1]

(d) Outline the process of saltatory conduction. [2]

Textbook topics in this question

Review the exact course sections assessed by each question part.

Mixed-topic question
5(a)7.2 Nervous Systems and Neuron Structure
5(b)7.2 Action Potentials and Impulse Conduction
5(c)7.2 Action Potentials and Impulse Conduction
5(d)7.2 Action Potentials and Impulse Conduction