What is included within the CNS?
- Brain
- Spinal cord
What does the brain and spinal cord lie within?
The skull and vertebral canal
What are the names of the 3 meninges that cover the brain and spinal cord?
- Dura mater
- Arachnoid membrane
- Pia mater
What are the 5 different segments of the spinal cord?
- Cervical
- Thoracic
- Lumbar
- Sacral
- Coccygeal
What does grey matter contain?
- Neuron cell bodies and some axons
What does white matter contain?
- Nerve axons
Where is the dorsal horn grey matter located?
- In the posterior part of the spinal cord
Where is the location of first-order afferent neuron terminals?
- Dorsal horn grey matter
What contains cell bodies of second-order sensory neurons?
- Dorsal horn grey matter
Where is ventral horn grey matter located?
- In the anterior part of the spinal cord
Which is bigger, the dorsal horns or the ventral horns?
The ventral horns
What does the ventral horn grey matter contain?
- Cell bodies of motor neurons
Where do moto nerve axons leave the spinal cord via?
Ventral nerve roots
What do the regions of the spinal cord look like after being stained and why?
Stained for myelin so:
- White matter stains dark
- Grey matter stains light/ appears pale
Why is there relatively more white matter in the cervical and thoracic regions than lumbar and sacral?
- The cervical region has more white matter because the cervical region works the upper limbs of the body. In order for our fingers to move quickly, presence of more myelinated axons are needed. In lower segments of the spinal cord, there is less white matter because there are fewer axons travelling to and from the brain
Why is there a greater amount of grey matter in cervical and lumbar regions?
- In the cervical segment, the ventral horn is enlarged. Also in the lumbar segment, the ventral horn is large. These segments are those that contain motor neurons that control movement of the arms and legs
What mechanism is the reflex pathway associated with?
- The protection mechanism
What 3 neurons are associated with the reflex pathway?
- Sensory neuron
- Interneuron
- Motor neuron
How is white and grey matter positioned in the spinal cord?
- White matter surrounds grey matter
How is white and grey matter positioned in the brain?
- Grey matter on outside - The cerebral cortex
- White matter on inside
What three regions of the brain are there?
- Forebrain
- Midbrain
- Hindbrain
What are the 2 regions of the forebrain?
- Cerebrum
- Diencephalon
What are the 3 regions of the hindbrain?
- Pons
- Medulla oblongata
- Cerebellum
What does the midbrain control?
- Visual and auditory reflexes
- Pain control
