14. NERVOUS SYSTEM II Flashcards
Describe the difference between the central nervous system and the peripheral nervous system.
The central nervous system includes the brain and spinal cord. The peripheral nervous system includes all nervous tissue in the body outside of the central nervous system.
Describe the role of the somatic nervous system
The somatic nervous system controls voluntary muscles and transmits sensory information to the central nervous system.
State TWO ways in which the following central nervous system components are protected:
a. Spinal cord
b. Brain
a. By the vertebral column and the meninges
b. By the cranium and the cranial meninges, CSF and the BBB
With regards to the layers of the meninges, compare functions of the:
a. Dura mater
b. Arachnoid mater
c. Pia mater
a. Dura mater is the tough outer layer that attach to the inside of the cranium and vertebral column for protection and support. It divides into two layers to create venous sinuses to drain blood out of the brain
b. Arachnoid mater is formed from collagen and elastic fibres helps to bridge the gap between the dura and pia mater.
c. Pia mater is a thin, transparent layer that contains blood vessels and it houses the subarachnoid space, filled with CSF
Name the spaces between:
a. Dura mater and arachnoid mater
b. Arachnoid mater and pia mater
a. Subdural space
b. Subarachnoid space
Name the neuroglial cell that maintains the BBB.
Astrocytes
Name TWO arteries that supply the brain.
Vertebral and Carotid arteries
List FOUR major parts of the brain.
Cerebrum
Cerebellum
Diencephalon (Thalamus; hypothalamus; epithalamus)
Brainstem (medulla oblongata; pons; midbrain)
Name the area of the brain that contains the ‘pineal gland’.
Diencephalon
List THREE factors that can damage the cerebellum.
- Chronic alcohol abuse
- Coeliac disease
- Thiamine (Vit B1) deficiency
List TWO functions of the cerebellum
- Maintenance of posture and balance
- Co-ordinate and smooth complex sequences of movement
- Correction of errors during ongoing movement
Name the area that connects the two cerebral hemispheres.
Corpus callosum
Name which cerebral lobe plays a role in:
a. Hearing
b. Vision
c. Motor skills
d. Sensory input
a. Temporal lobe
b. Occipital lobe
c. Frontal lobe
d. Parietal lobe
Which part of the brain may be damaged where symptoms of ‘ataxia’ are presenting?
The cerebellum
Describe how the left and right side of the brain co-ordinates the body.
The left side of the brain co-ordinates the right side of the body while the right side of the brain co-ordinates the left side of the body. This is because the corticospinal tracts cross over in the medulla oblongata.
Name THREE main structures within the limbic system.
Hypothalamus
Hippocampus
Amygdala
Name the area that plays a key role in emotions within the limbic system.
Amygdala
Name ONE cranial nerve which if damaged can lead to double vision.
Oculomotor (III)
Trochlear (IV)
Abducens (VI)
Name the largest cranial nerve of the autonomic nervous system.
Vagus nerve (X)
Name TWO cranial nerves that exhibit both sensory and motor functions.
Facial nerve (V) Trigeminal nerve (VI) Hypoglossal nerve (IX) Vagus nerve (X)
State where the spinal cord terminates.
At the vertebral level of L2 as the ‘conus’
Describe the difference between ‘motor tracts’ and ‘sensory tracts’ in white matter.
The motor tracts in spinal white matter are descending and the control voluntary and involuntary movement.
The sensory tracts are ascending and they transmit impulses from the skin, tendons, muscles and joints to the brain.
Describe the difference between ‘dorsal horns’ and ‘ventral horns’ in grey matter
The dorsal (posterior) horn receives sensory impulses whilst the ventral (anterior) horn sends out motor impulses
With regards to the spinal cord tracts, which is responsible for:
a. Pain and temperature
b. Voluntary movement
c. Light touch, vibration, proprioception
a. Spinothalamic tract
b. Corticospinal tract
c. Dorsal columns
Explain what could happen if there is damage to any of the spinal tracts
It would lead to loss of the tract’s function below that level of the body
Describe in detail the ‘reflex arc’
A reflex is a very fast, automatic, unplanned sequence of actions that occurs in response to a stimulus and includes:
- Sensory receptor
- Sensory neuron
- Interneuron
- Motor neuron
- Effector organ