Anatomy & Physiology I - Spinal Cord and Peripheral Nervous System Flashcards

Flashcards based on lecture notes covering the spinal cord, peripheral nervous system, sensory receptors, and related anatomical structures.

When is the final exam for Anatomy & Physiology I?

Monday 5/6/2024 10:15-12:15pm

What is the emphasis of the final exam?

Unit 4 materials, with relevant materials from previous units also tested.

What type of potential occurs when receptors for general senses are stimulated?

Generator potential

What happens before a stimulus arrives in sensory reception?

Ion channels in the axolemma of the somatic sensory neuron are closed.

What triggers an action potential in sensory reception?

Voltage-gated Na+ channels opening when the membrane potential reaches threshold.

How are sensory receptors classified by location of stimuli?

Exteroceptors, Interoceptors, and Proprioceptors

What do exteroceptors detect and where are they usually located?

Detect stimuli originating from outside the body and are usually close to the body’s surface.

What do interoceptors detect and where are they usually located?

Detect stimuli from visceral organs and are usually found within the body’s interior.

What do proprioceptors detect and where are they located?

Detect relative position of body parts and tension on the musculoskeletal system; found in skeletal muscles, tendons, joint capsules, and the inner ear.

How can receptors be classified based on the type of stimuli they receive?

General senses and Special senses

How are General and Special senses transmitted to the CNS?

General senses are transmitted via pseudounipolar neurons, while special senses are transmitted via bipolar neurons.

Define somatic senses.

From skin, muscle, bones, joints (usually easily located)

Define visceral senses.

From internal organs (usually more difficult to locate).

What is Adaptation in the context of sensory receptors?

The nervous system's ability to detect changes but not adapt well to constant stimuli.

What is Troxler’s fading effect an example of?

Adaptation; photoreceptors in the eyes start to block out areas that you are not paying attention to.

Where does the spinal cord extend from?

From the foramen magnum to vertebrae L1 or L2.

List the anatomical features seen on the spinal cord.

Cervical enlargements, Lumbar enlargements, Cauda equina, Conus medullaris, Filum terminale

List the anatomical features seen on a cross-section of the spinal cord.

Posterior median sulcus, Anterior median fissure, Spinal nerve roots (composed of rootlets), Dorsal root ganglia, white and gray matter, Meninges (dura, arachnoid, pia mater)

How is gray and white matter positioned in the brain vs. the spinal cord?

In the spinal cord, white matter is on the outside and gray matter is on the inside. In the brain, gray matter is on the outside and white matter is on the inside.

What are the components of spinal nerve roots?

Anterior root and Posterior root

What is the central canal of the spinal cord filled with?

CSF

What connects each "butterfly" wing of the spinal cord?

Gray commissure

What type of neurons are in the anterior wings of the spinal cord?

Lower motor neurons

What type of neurons are in the posterior wings of the spinal cord?

Sensory interneurons

What is lumbar puncture?

Needle inserted into subarachnoid space between fourth and fifth lumbar vertebrae to withdraw CSF

Name the structures related to one another (root, nerve, ramus, plexus, tract, and ganglion)

Tree trunk ~ spinal nerve, Roots ~ spinal nerve root, Tree branches ~ spinal rami

What are the four spinal nerve plexuses?

Cervical plexus, Brachial plexus, Lumbar plexus, Sacral plexus

What type of information do posterior and anterior rami carry?

Both carry somatic motor and sensory information.

What is the general function of spinal nerve plexuses?

Transmit nerve signals to/from the CNS and distinctive body regions.

What are funiculi?

General regions of spinal white matter including posterior, lateral, and anterior funiculus.

In what funiculi do sensory pathways travel?

Posterior and lateral funiculi

In what funiculi do motor pathways travel?

Anterior and lateral funiculi

What is a dermatome?

A segment of skin supplied by a specific spinal nerve with somatic sensation.

How are dermatomes used clinically?

To test the integrity of sensory pathways to different parts of the body.

What causes shingles and what pattern does it follow?

Caused by the same virus that causes chicken pox and follows dermatomal patterns.

What is referred pain?

Pain that originates in an organ but is perceived as cutaneous pain.