Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Stack #215244
Neuro Unit II Lecture 4
| Question | Answer |
|---|---|
| Sensory endings throughout the body are separated into ______ categories based on what? | 3; their location |
| What are the three categories of sensory endings? | Exteroceptors, Proprioceptors, visceroceptors |
| Sensory Ending 1: Exteroceptors are located where? What do they respond to? | In the skin; they respond to touch pressure pain temp |
| Sensory Ending 2: Proprioceptors are located where? What do they respond to? | Muscles, tendons, joints; provide info for reflex adjustment of muscle tension and awareness of position and movement |
| Sensory Ending 3: Visceroceptors are located where? What do they respond to? | mesentery and hollow organs; involved in visceral reflexes and mediate sensation of fullness and discomfort |
| How are these broad categories different from the ion channels (chemo, mechano, and photo receptors) from lecture 3? | The categories are separated based on where they are located. Each one, such as the skin, could have multiple different kinds of ion channels that form receptor potentials. |
| Exteroreceptors that are mechanoreceptors in the skin: name 5 of them. What types of fibers supply them? What division of the dorsal root are they from?(See lecture 3 to see what each responds to) | Hair follicle, Meissner, Merkel, Pacinian, Ruffini; A alpha/beta fibers; medial division of the dorsal root; THE COMPLETELY DIFFERENT ONE IS FREE NERVE ENDINGS |
| Exteroreceptor THAT IS NOT A MECHANORECEPTOR in the skin - What is the odd ball sensory ending in the skin? | Free nerve endings; C fibers, lateral division of the dorsal root, senses pain, temp |
| Branches of what nerves supply the skin? Explain how they distribute. | Branches from spinal and cranial nerves. They form a plexus in the dermis |
| Proprioceptors - What are the three principle types? | Golgi tendon organs (GTOs), muscle spindles, and ruffini endings |
| Proprioceptors - What do muscle spindles signal? Where are they located? | Length and rate of change of length. Located inside of muscle. (Have special motor innervation (gamma) to allow them to contract with muscles) |
| For muscle spindles, what excites them? What slows down their activation? | Passive stretching excites, contracting relaxes |
| Proprioceptors - What do GTO's signal? Where are they located? | Tension, they are located in the tendon near the junction of the tendon to the muscle. |
| What sense organ is organized in paralell to a muscle? What about in series? | parallel = spindles, series = GTOs |
| What system do all of the Exteroreceptors (EXCLUDING the free nerve endings) and ALL of the Proprioreceptors feed into? | The Dorsal Column Medial Lemniscal system (DCML Sys) |
| The DCML sys is the ________ and ________ sense for the entire body except the ________ which is done by the ___________ system. | discriminative tactile; position; head; trigeminal |
| What are the main fxs of the DCML? | 1. location and intensity of static & moving mechanical stimuli. 2. flutter/vibration 3. Two point discrimination and stereognosis (discriminative touch) (see defn card) 4. Proprioception 5. Kinesthesis |
| What is stereognosis? What sensory endings are responsible for it in the DCML? | The ability to recognize size, shape, and texture via palpation (this is discriminative touch and is NOT the same as crude, poorly localized, touch as in the AL sys!!), Merkels and Meissners |
| What is proprioception? | The ability to know where ones limbs are in space |
| What is kinesthesis? | The ability to know if ones limbs are moving |
| What receptors are responsible for proprioception in the DCML? | Spindles, GTO's, Ruffini |
| What sensory endings are responsible for kinesthesis in the DCML? | SPindles, GTO's, Ruffini, Meissners, and Merkels |
| What does Dorsal Columns refer to as part of the DC-ML Sys? Do they carry info from ipsilateral or opposite side from where the DRG cell bodies are? | The white matter tracts in the dorsal funiculus. SAME SIDE AS DRG CELL BODIES and WHERE STIMULUS OCCURED!! |
| What does Medial Lemniscal refer to as part of the DC-ML Sys? Does it carry info from ipsilateral or opposite side from where the cell bodies are? | ML refers to the part of the system ROSTRAL to the medulla. (neurons 2-4!) ON OPPOSITE SIDE from where stimulus occurred!!!! |
| How many neurons are in the chain for the DC-ML system? Where are the cell bodies?? | 4 neurons. 1. DRG, 2. Cuneate nucleus or Gracilis nucleus in lower medulla. 3. Ventroposterolateral (VPL) nucleus of the thalamus 4. To Somatosensory cortex (SI) |
| Where do the fibers of the DC-ML sys cross over? What is the fiber called that this crossing over occurs in and where do they go from there? | Cross over in the lower part of the medulla. Internal arcuate fibers. These fibers continue up to the VPL within the ML part of the sys. |
| T/F: All of the fibers that enter in the medial division of the dorsal root ascend in the dorsal funiculi. | FALSE!! Some become collateral branches and terminate on 2nd order neurons in the dorsal horn. |
Created by:
StudyBuddies
Popular Medical sets