Central Nervous System II

These flashcards cover key concepts from the lecture on the Central Nervous System, focusing on the anatomy and function of the meninges, cerebrospinal fluid, blood-brain barrier, spinal cord anatomy, and neurological pathways.

What are the functions of the meninges?

Cover and protect the CNS, blood vessels, enclose venous sinuses, and contain cerebrospinal fluid.

What are the three layers of the meninges?

Dura mater, arachnoid mater, and pia mater.

What is the strongest layer of the meninges?

Dura mater.

What attaches the periosteal layer of the dura mater?

It attaches to the inner surface of the skull.

Where is the dural venous sinuses formed from?

From the separation of two layers of the dura mater.

What is the function of the arachnoid mater?

It contains spider web-like extensions and houses the subarachnoid space with cerebrospinal fluid.

What occurs in the subarachnoid space?

It contains cerebrospinal fluid and the largest blood vessels of the brain.

What is the delicate layer that clings tightly to the brain?

Pia mater.

What is meningitis?

Inflammation of the meninges, which can lead to encephalitis.

What constitutes cerebrospinal fluid (CSF)?

A watery solution derived from blood plasma with lower protein levels.

What is the primary function of cerebrospinal fluid?

To give buoyancy to CNS structures, protect from trauma, and nourish the brain.

Where is the choroid plexus located?

Hangs from the roof of each ventricle.

What is hydrocephalus?

An obstruction that blocks the circulation or drainage of cerebrospinal fluid, leading to increased pressure.

What is the role of the blood-brain barrier?

Helps maintain a stable environment for the brain and prevents harmful substances from entering.

What type of junctions are present in the blood-brain barrier?

Tight junctions.

What are the spinal cord's protective layers?

Bone, meninges, and cerebrospinal fluid.

How many pairs of spinal nerves are there?

31 pairs.

What does the term 'cauda equina' refer to?

A collection of nerve roots at the inferior end of the vertebral canal.

What type of matter makes up the internal structure of the spinal cord?

Gray matter in the core and white matter outside.

What is the location of dorsal and ventral roots?

Dorsal roots carry sensory input; ventral roots carry motor output.

What does the gray matter of the spinal cord resemble in cross-section?

A butterfly or the letter 'H'.

What is the composition of white matter in the spinal cord?

Myelinated and nonmyelinated nerve fibers that allow communication.

What are the three directional pathways of white matter in the spinal cord?

Ascending, descending, and transverse.

What comprises the ascending pathways of the spinal tract?

Three neurons: first-order, second-order, and third-order neurons.

What is the purpose of descending pathways?

To deliver efferent impulses from the brain to the spinal cord.

What is the default condition for pathways along the CNS in terms of symmetry?

Pathways are paired symmetrically (left and right).

How does the scanning of CSF occur?

Via lumbar puncture to observe microbes.

What is the major function of the spinal cord?

Provides two-way communication between the brain and body.

What are the enlargements in the spinal cord?

Cervical and lumbar enlargements.

What occurs at the conus medullaris?

The spinal cord terminates.

What is the function of the dorsal horn?

Contains interneurons that receive sensory input.

What reflects the spinal cord's organization regarding sensory and motor neurons?

Gray matter is divided based on somatic and visceral innervation.