Nervous system

The term stimulus refers to

• the ability of an organism to respond.

• the extent of changes in the surrounding.

• a change in the environment.

• a change in the pH of the water.

Impulses are conveyed from the central nervous system to the muscles by a/an

• efferent neurone.

• afferent neurone.

• sensory neurone.

• interneurone.

Pick out the WRONG statement

concerning the function of the nerve cell.

• It can convey impulses in both directions.

• It does not weaken the impulse passing through it.

• It conveys messages in the form of electrical impulses.

• It conveys impulses to the effector organs.

Which one of the following neurones conveys impulses from the afferent neuron to the efferent neuron?

• Axon.

• Dendron.

• Synapse.

• Interneuron.

The part of the brain labelled Z controls the center which serves all of the following except

• Cardiac inhibition.

• Visual interpretation center.

• Respiratory center.

• Vaso contraction center.

The structure above is a type of neurone. Name the neurone

• Interneurone.

• Afferent neurone.

• Efferent neurone.

• Free neurone.

The figure above shows a cross section of a mammalian spinal cord. The part which contains neurons that transmit impulses from the brain to the effector is

• I only

• II only.

• III only.

• IV only.

The figure below shows the structure of

the synaptic knob. What is P and its function?

• Mitochondrion: Generates energy to send impulse

  across the synapse.

• Vesicle: Secretes neurotransmitter.

• Mitochondrion: Sends impulse to the cell body.

• Vesicle: Sends impulse to the terminal of

  the synaptic konb.

Nerve impulses travel from

I V to Z.

II Z to X.

III X to V.

IV Y to W.

• I only.

• I and II only.

• I and III only.

• IV only.

Effectors which are beyond voluntary control include

I triceps muscles.

II iris muscles.

III salivary glands.

IV ileum muscles.

• I, II and III only

• II, III and IV only.

• III and IV only.

• I, II, III and IV only.