Test 2.2 Flashcards
What are the two pathways for spinothalamic system
Spinal- limbs and truck
Trigeminal -face and neck
Where do mechicoreceptors in the spinal system send info to?
Into dorsal root then info is sent from the legs to arm
What are the 2 branches of first order sensory neurons
Peripheral- sensory receptor
Central-branches into a number of axon collaterals
What does the sensory pathway consists of for spinothalamic system
First order neuron- peripheral sensory axon
Second order neuron- spinal and or medulla
Third order neuron- always in thalamus
Where is the body of the second order neuron in the dorsal column system
It is in the caudal medulla and the axon decussates in the caudal to rostal medulla
What is referred pain due to
Deals with info converging on second order neuron
Where does pain modulation (gating) originate
In midbrain and rostal medulla
What is spinal cord damage dependent on
Second order neuron
What does pain modulation effect?
Effects each site through endogenous opioids
What happens when you apply pressure to pain
You activate larger sensor fibers that have direct inhibition response to pain fibers
Explain brown - Sequard syndrome
Complete damage to half of spinal cord resulting in loss of spinothalamic on co-lateral side and loss of dorsal column system on opposite side
What fluid is the eye full of
Vitreous humor fluid
What is sclera
External connective tissue that coat the eyeball
What does the cornea do
Transparent surface of the eyeball in front of the eye that bends light
Explain the function of the Lens
Transparent structure actively focuses light on the retina
What’s the function of the retina
Neural component of the eye that contains cells that conduct phototransduction and initial visual processing
What’s does cilliary body muscle do
Controls focus of lens by increasing refractive power
What does iris muscles do
Controls amount of light entering eye by either constriction or dilation
True or false
The fovea is not highly concentrated
False it is
What is the region surrounding the fovea
Macula lutea
True or false
The optic disk has receptors
False it does not its the hole in your vision
What’s the sequence of phototransduction
1) activation of G-Protein transducer
2) activation of phosphodiesterase
3) cGMP concentration is reduce
What does bipolar cell do
Cell determines weather response to light is an “on” or “off” response
What’s the characteristic of ganglion cell
Only cell that produces action potentials
What’s the characteristic of photoreceptors
Light is transduced in this cell (uses a lot of energy)
Name the cell that sharpens images
Horizontal cell
What does spinothalamic system control
Pain and temperature
