Chapter 49 - Nervous Systems

Question 1

Describe general structure and function of the central nervous system, including supporting cells.

Answer 1

• Brain
• Spinal cord
• Glia cells
  
  • Support & protect neurons
  • Astrocytes:
    
    • increases blood flow to active neurons
    • acts in blood-brain barrier
  • Oligodendrocytes & Schwann cells:
    
    • Form myelin axon sheaths in vertebrates
  • Phagocytic microglia:
    
    • “Immune system” attacking mistakes from blood-brain barrier
  • Ciliated ependymal cells:
    
    • Line ventricles and help with fluid circuliation
    • “Provide cushion”

Question 2

Describe general structure and function of the peripheral nervous system, including supporting cells.

Answer 2

• Cranial nerves
• Ganglia outside central nervous system
• Spinal nerves
• Further divides…
  
  • Efferent neurons:
    
    • Motor system:
      
      • Locomotion:
        “Voluntary” (Mostly)
        Responds to external stimuli
        Carries signals to & from skeletal muscles
    • Autonomic nervous system:
      
      • “Involuntary”
        Responds to internal cues in other systems
        
        • Sympathetic division:
          “Fight or dlight”
        • Parasympathetic division:
          “Rest and digest”
        • Enteric division:
          Controls secretion/peristalsis
  • Afferent (sensory neurons):
    
    • Ex: hearing

Question 3

Describe major functions of the brainstem.

Answer 3

Described as the “lower brain”:

• Homeostasis & basic-life functions
• Coordination of large-scale movement
• Regulates wakefulness
• Transmission of information between other parts of brain
• Includes:
  
  • Midbrain
  • Pons
  • Medulla oblongata

Question 4

Describe major functions of the cerebellum.

Answer 4

• Responsible for coordination & error-checking of movement & balance (Think hand-eye coordination)
• Motor skills (habits! Like, never forget how to ride a bike)

Question 5

Describe major functions of the diencephalon.

Answer 5

• Epithalamus:
  
  • Includes pineal gland
• ​Thalamus:
  
  • Cerebrum’s input & output centre
• ​Hypothalamus:
  
  • Homeostasis & “pure” behaviours
  • Produces hormones
  • Biological clock

Question 6

Describe major functions of the cerebrum.

Answer 6

• Consists of right and left hemispheres:
  
  • Control opposite sides of body.
  • Each with four-lobed cortex.
• Responsible for perception, learning, voluntary movement, emotions, conscousness, memory.