Nervous System Flashcards
What is the nervous system divided into?
- Central nervous system and peripheral nervous system
What is the CNS comprised of?
- The brain and spinal cord
What is the peripheral nervous system comprised of?
- Spinal nerves exiting the spinal cord
- Peripheral nerves
- Muscles
What are nerve cells called?
Neurons
What connects neurons together?
Axons
What do axons do?
They conduct impulses from one neuron to another
What is the largest part of the brain called?
Cerebrum
How is the cerebrum divided into?
Two halves called cerebral hemispheres
What are the cerebral hemispheres divided into?
- Frontal lobe
- Parietal lobe
- Temporal lobe
- Occipital lobes
What type of tissue can brain tissue be?
- White
- Gray
What does Gray matter consist of?
- Aggregations of neuronal cell bodies
*forms the cerebral cortex
What does white matter consist of?
- Neuronal axons that are coated with myelin
What creates the white color of white matter?
The myelin sheathes creates the white color
*which allows nerve impulses to travel more rapidly
What are basal ganglia and where are they located?
What are they?: they are additional clusters of gray matter that are deep in the brain; they affect movement
Located: deep in the brain
What is the inferior surface of the frontal lobe called?
Diencephalon
What does the diencephalon include?
- Thalamus
- Hypothalamus
What does the thalamus do?
Processes sensory impulses and relays them to the cerebral cortex
What does the hypothalamus do?
- Maintains homeostasis and regulates temperature, heart rate, and blood pressure
- Affects endocrine system and governs emotional behaviors
*anger
*sexual drive
What is the internal capsule?
- A white matter structure
What does the internal capsule contain?
- The corticospinal tract
*The internal capsule has myelinated fibers converge from the cerebral cortex and descend into the brain stem
What does the brain stem connect?
- The upper part of the brain with the spinal cord
What are the sections of the brain stem?
- Midbrain
- Pons
- Medulla
What does consciousness rely on?
All of these structures must be intact
1. Cerebral hemispheres
2. Diencephalon
3. Upper brain stem
4. Reticular activating (Arousal) system
What does the cerebellum do?
- Coordinated movement
- Helps the body be upright in space
What connects directly to the spinal cord?
The brain stem
Does the spinal cord have gray and white matter?
Yes
What is the spinal cord encased within?
Vertebral column
*Ends at L1, L2
Where do motor signal exit the spinal cord?
Through anterior nerve roots
Where do sensory signals exit the spinal cord from?
Posterior nerve roots
What do the posterior and anterior roots combine to?
Spinal nerves (which form the peripheral nerves)
What are the segments of the spinal cord?
C1 to C8
T1 to T12
L1-L5
S1 to S5
Where is the spinal cord the thickest?
The cervical segment
Where should lumbar punctures be performed at?
L3 to L4 OR
L4 to L5