The CNS and PNS Flashcards
What portions does the PNS consist of?
Somatic and autonomic
What is the autonomic portion of the PNS concerned with?
Unconscious sensation and involuntary movement
What does the autonomic portion of the PNS consist of?
- Sympathetics
- Parasympathetics
- Enteric system
What is the somatic portion of the PNS concerned with?
Conscious sensation and voluntary movements
What are the parts of the CNS?
- Cerebrum
- Cerebellum
- Brainstem
- Spinal cord
What is the cerebrum concered with?
Higher cognitive function, e.g. eye movements, primitive aspects of hearing and vision
What is the cerebrum concerned with?
- Potential cognitive functions
- Coordination
What are the parts of the brainstem?
- Midbrain
- Pons
- Medulla
What are the functions of the midbrain?
- Eye movements
- Primitive aspects of hearing and vision \
What are the functions of the pons?
- Cochlear and vestibular centres
- Connecting the two halves of the cerebrum
- Feeding
How is the pons involved in feeding?
It contains the pattern generator for chewing
What is the function of the medulla?
- Autonomic functions - CVS regulatory centres, pattern generator for breathing
- Connects brain to spinal cord
Can the CNS regenerate?
No, apart from certain regions
Give two examples of exceptions to the rule that the CNS cannot regenerate
- Olfactory nerves
- Pituitary stalk axons
Can the PNS regenerate?
Yes, but not always perfectly
How do the CNS and PNS differ in terms of sophistication?
The CNS is sophisticated, the PNS is not
What kind of tumours can the CNS get?
Benign or malignant
What tumours can the PNS get?
Tend to only get benign tumours, e.g. benign Schwannomas
What myelinates CNS neurones?
Oligodendocytes
What myelinates PNS neurones?
Schwann cells
Describe the immune response of the CNS?
Attenuated, therefore infections are very serious
Describe the immune system in the PNS?
Macrophages in PNS, and other immune cells can access
Describe the lymphatic drainage of the CNS
The CNS has a glymphatic system, where drainage mostly occurs at night
What is the result of glymphatic drainage mostly occuring at night?
Less sleep results in reduced removal of denatured proteins, so increased risk of Alzheimers
Describe the lymphatic drainage of the PNS?
Normal lymphatic system
