PNS Structure and Function

Question 1

somatic division

Answer 1

-carrier sensory signals from the body that are consciously perceived
-carries voluntary motor signals from the brain
-neurotransmitters are released into small discrete sites
-ACh is the transmitter used in the synapse between a neuron and a skeletal muscle

Question 2

autonomic division

Answer 2

-ACh or NA are the neurotransmitters used in the synapses between postsynaptic neurons and effector tissue
-carries sensory and motor signals that operate without conscious awareness
-neurotransmitters are released widely
- ACh is the transmitter used in the synapse between presynaptic and postsynaptic neurons

Question 3

sympathetic system

Answer 3

-presynaptic axon is short and postsynaptic axon is long
-ganglia are present near the spinal cord
-nerves leave from the thoracic and lumbar regions of the spinal cord
fight or flight and acts o mobilize the body during activity

Question 4

parasympathetic system

Answer 4

-presynaptic axon is long and postsynaptic axon is short
-ganglia are near the target organ
-nerves leave from the brain and sacral region of the spinal cord
rest and digest response and promotes maintenance functions and conserves body energy

Question 5

adrenal medulla

Answer 5

is located int he middle part of the adrenal gland. adrenal medulla cells synthesise adrenaline and nonadrenaline. these hormones are secreted directly into the bloodstream by chromaffin cells. chromaffin cells are postsynaptic sympathetic neurons that lack axons. because they act as hormones, adrenaline and noradrenaline may affect tissues far away from their point of release, and result in a systemic fight or flight response