Nervous System - Module 3

Question 1

What are the parts of a Neuron?

Answer 1

• Dendrite - conduct impulses towards the cell (branch-like appearance)
• Axon - conduct impulses away from the cell (each nerve ending has 1 axon)
• Myelin Sheath - fatty tissue that covers the axon to protect it and speed up impulses as they travel
• Synapse - space between a dendrite and axon
• Neurotransmitter - special chemicals which help axons jump synapses

Question 2

What are the parts of the brain?

Answer 2

• Cerebrum - largest/highest sect. of brain (Separated into frontal, parietal, temporal, and occipital lobes) concerned with reasoning, sense, speech, and voluntary control
• Diencephalon - (mini brain) Includes two parts: thalamus and hypothalamus
• Thalamus - (walnut shaped, above hypothalamus) directs sensory impulses towards cerebrum
• Hypothalamus - (below thalamus) controls ANS, body temp., appetite, water balance, sleep, blood vessel constriction, and emotions
• Cerebellum - (below cerebrum) responsible for muscle coordination/tone and balance/posture

Question 3

What are the parts of the brain stem?

(3 parts)

Answer 3

• Midbrain - (most superior) conducts impulses to other parts of brain for optic/audio reflexes
• Pons - (b/w Midbrain and Medulla) directs messages to other brain parts for mastication, tasting, salivation, and (helps with) respiration
• Medulla Oblongata - (most inferior–connects w/ spinal cord) regulates heartbeat, respiration, swallowing, coughing, and BP

Question 4

What protects the CNS?

Answer 4

• Skull
• Vertebrae
• Meninges (Dura/Arachnoid/Pia Mater)
• Dura Mater - outermost layer
• Arachnoid - middle layer
• Pia Mater - innermost layer
• Cerebrospinal Fluid (CSF) - flows throughout the brain and around spinal cord, fills brain ventricles (hollow spaces), and absorbs shock

Question 5

What is the purpose of the Spinal Cord?

Answer 5

Carries messages to/from the brain and nerves which go to muscles/glands

Question 6

What are the parts of the spinal cord’s protection?

Answer 6

• 7 Cervical Vertebrae
• 12 Thoracic Vertebrae
• 5 Lumbar Vertebrae
• Sacrum
• Coccygeal (coccyx)

Question 7

What should be done to prevent brain damage after a stroke?

Answer 7

Administer medication within the first 3 hours to break up clots