OCR General Certificate of Secondary Education (GCSE) Biology Practice Exam

What are the axons of neurons responsible for?

1. Receiving electrical impulses

2. Passing electrical impulses along

3. Coordinating muscle contraction

4. Detecting stimuli from the environment

The correct answer is: Passing electrical impulses along

The axons of neurons play a crucial role in the transmission of electrical impulses throughout the nervous system. They are long, slender projections that extend from the cell body of a neuron, allowing for the efficient relocation of electrical signals known as action potentials to other neurons, muscles, or glands. When a neuron is activated, the electrical impulse travels down the axon and reaches the axon terminals, where it can then communicate with neighboring cells through synapses. This process is essential for the functioning of the nervous system, enabling quick communication between different parts of the body and facilitating responses to stimuli. The other options relate to different roles within the nervous system or are functions associated with other parts of neurons or different types of cells. Receiving electrical impulses is primarily the role of dendrites, which collect signals from the environment or other neurons. Coordinating muscle contraction involves motor neurons and muscle fibers working together, but it is not the specific responsibility of axons. Detecting stimuli from the environment is the function of sensory receptors, which are specialized structures that convert external signals into nerve impulses that are sent to the brain for processing.