The Nervous System

Question 1

What is the difference between the CNS and PNS?

Answer 1

1. The CNS includes the brain and the spinal chord
2. The PNS consists of all the nerves in the body

Question 2

Where are upper motor neurons located and what do they do?

Answer 2

Upper motor neurons
1. Located in the motor cortex of the brain
2. Connect the cerebral cortex to the brain stem and spinal chord
3. Initiate voluntary movement throughout the body

Question 3

Where are lower motor neurons located and what do they do?

Answer 3

1. Located in the spinal cord
2. Synapse with skeletal muscles, organs, and glands

Question 4

What does the somatic nervous system do?

Answer 4

1. transmits and receives information from the senses
2. Controls voluntary muscular movements

Question 5

What spinal nerves are paired with: the cervical, thoracic, and lumbar part of the spine?

Answer 5

1. Cervical (8 pairs): Neck, shoulders, arms and hands.
2. Thoracic (12 pairs): Arms, chest, and upper abdomen.
3. Lumbar (5 pairs): Lower abdomen, hips and legs.

Question 6

What spinal nerves are paired with: the sacral and coccygeal part of the spine?

Answer 6

4. Sacral (5 pairs): Legs, foot and lower digestive tract.
5. Coccygeal (1 pair): Muscles of the pelvic region.

Question 7

What is the autonomic nervous system in charge of?

Answer 7

1. in charge of the involuntary and unconscious control of processes of the body
2. regulates automatic (involuntary) responses to stimuli

Question 8

What is role of the sympathetic nervous system?

Answer 8

“Fight, flight or freeze”
1. mobilises the body to deal with danger through hormones and physical changes

Question 9

What is the role of the parasympathetic nervous system?

Answer 9

“Rest and digest
1. Counteracts the sympathetic nervous system
2. Slows the heart rate and stress hormones

Question 10

What does a sympathetic neuron look like?

Answer 10

2. Short Preganglionic neuron
3. Long post ganglionic neuron
4. Neuron to target organ

Question 11

What does a parasympathetic neuron look like?

Answer 11

1. Longganglionic neuron
2. Short post ganglionic Neuron

Question 12

If heart rate rises, which nervous system did this? Parasympathetic or Sympathetic?

Answer 12

Sympathetic rises heart rate

Question 13

If digestive organs are stimulated, which nervous system did this?

Answer 13

Parasympathetic stimulates rest and digest

Question 14

Name the three important parts of the axon terminal in chemical synapses and what they do

Answer 14

1. Synaptic vesicles - contain neurotransmitters
2. Synaptic cleft - small gap between axon terminal and postsynaptic cell membrane
3. Voltage gated Ca++ channel - triggers synaptic vesicles to release neurotransmitters

Question 15

How are electrical synapses different to chemical synapses?

Answer 15

1. Found in the brain and the spinal chord
2. Ions flow directly from one cell into another through the GAP JUNCTION.
3. Allows two way transmission.

Question 16

What neurotransmitters does the Somatic Nervous system use?

Answer 16

1. Acetylcholine (ACh) by lower motor neurons
2. Glutamate by upper motor neurons

Question 17

What neurotransmitters does preganglionic sympathetic and parasympathetic neurons use?

Answer 17

1. Acetylcholine

Question 18

What neurotransmitters does postganglionic sympathetic use? How about postganglionic parasympathetic neurons?

Answer 18

1. Sympathetic - Noradrenaline
2. Parasympathetic - Acetylcholine

Question 19

What is the enteric nervous system? What does it control

Answer 19

1. Mesh-like network of neurones in gastrointestinal lining
2. Controls segmentation and peristalsis (contractions of the smooth muscle gut

Question 20

What are the two nerve plexuses in the enteric nervous system? What do they do?

Answer 20

1. Myenteric plexus - regulates motor activity
2. Submucosal plexus - secretomotor activity

Question 21

How do sensory neurons work?

Answer 21

1. Activated by sensory input from the environment
2. Carry impulse into the CNS
3. Takes physical information (such as light) and converts it into information that the brain can process