Pns and cns

Question 1

Structure of the central nervous system (CNS) and the peripheral nervous system (PNS)

Answer 1

The CNS consists of the brain and the spinal cord.

The PNS consists of the somatic nervous system (SNS) and the autonomic nervous system (ANS).

Question 2

The somatic nervous system contains sensory and motor neurons.

Answer 2

Sensory neurons take impulses from sense organs to the CNS. Motor neurons take impulses from the CNS to muscles and glands.

Question 3

Autonomic Nervous System

Answer 3

The autonomic nervous system (ANS) consists of the sympathetic and parasympathetic systems.

Question 4

The antagonistic actions of the sympathetic and parasympathetic systems on heart rate, breathing rate, peristalsis and intestinal secretions.

Answer 4

The sympathetic system speeds up heart rate and breathing rate while slowing down peristalsis and production of intestinal secretions. The parasympathetic system changes these in the opposite way.

Question 5

Converging Neural Pathway

Answer 5

In a converging neural pathway, impulses from several neurons travel to one neuron. This increases the sensitivity to excitatory or inhibitory signals.

Question 6

Diverging Neural pathway

Answer 6

In a diverging neural pathway, impulses from one neuron travel to several neurons so affecting more than one destination at the same time.

Question 7

Reverberating Neural Pathway

Answer 7

In a reverberating pathway, neurons later in the pathway link with earlier neurons, sending the impulse back through the pathway. This allows repeated stimulation of the pathway.