topic.7.the.senses.powerpoint.7.0.sensory-receptors.balance Flashcards
What are special senses?
receptors placed in unique organs
olfaction/smell/nose
gustation/tase/tongue
Sensory receptors are formed by..
Function:
terminals of afferent neurons or specialized cells that bind with afferent neurons
function: gather info about the internal and external environment
How do sensory receptors respond to stimuli?
signal transduction: conversion of a stimulus to an membrane potential
How: changing their conductance(ions)
When a cell synapses with an afferent neuron, what type of receptors have this mechanism?
Mechanoreceptors, Photoreceptors, Chemoreceptors
what is the acronym to remember the 5 receptors
Many people can’t trust naps
Mechanoreceptors, Photoreceptors, Chemoreceptors, Thermoreceptors, Nociceptors
Mechanoreceptors
detect mechanical energy
changes in body position,
pressure, acceleration
Photoreceptors
detect light and are located in the eye
Chemoreceptors
detect specific molecules or conditions
such as acidity (e.g., taste buds)
thermoreceptors
temperature
Nociceptors-
detect tissue damage or noxious chemicals.
Their activity leads to pain
mechanoreceptors detect
-Meissner corpuscle
-Merkel receptor
-Pacinian corpuscle
-Ruffini corpuscle
What mechanoreceptors detects a drink about to slip out of my hand?
-Meissner corpuscle; detects low frequency vibrations
What mechanoreceptors allows me to differentiate blind folded between a broccoli and carrot?
Merkel receptor
detect fine details like point/edges/texture/curvature
What mechanoreceptors allows me to use tools or use a knife to cut fruit?
Pacinian corpuscle
high frequency vibrations
What mechanoreceptors allow me feel the flex in my hand when i extend them?
Ruffini corpuscle
detect hand shape and finger control
Proprioception
the sense of the relative position of
neighboring parts of the body.
**monitor/maintain body and limb positions
proprioception is composed of
1.sensory neurons in the inner ear that detect motion and orientation
2.mechanoreceptors/stretch receptors
stretch receptor are a type of …
mechanoreceptor and proprioceptor
What type of receptor are proprioceptors?
mechanoreceptor
Stretch receptors are found in
muscles and tendons
Golgi tendon organ (GTO):
example of a stretch receptor found in tendon;
detects position and movement
the limbs by detecting how much and how fast a muscle is stretched
balance involves
vestibular system of the inner ear
difference between proprioceptors and mechanoreceptors
proprioceptors: limbs of the body
mechanoreceptors: balance
vestibular apparatus made up of what parts?
3 semicircular canals: horizontal/posterior/superior
2 fluid-filled chambers: utricle and saccule
What is the function of the vestibular apparatus?
***Perceives the position and
the motion of the head using
mechanoreceptors
semicircular canal
detects rotational motions
filled with endolymph(high k+)
between membrane and bond of semicircular canal we can find what?
Perilymph (rich in Na+)
Ampulla is located where?
Ampulla (region at the base of a semicular canal with sensory hair cells
What is the function of the ampulla?
detects rotational movement of the head/body
cupula
gelatinous membrane sits on top of sensory hairs/afferent cells
How does the ampulla perform its function
- movement of head or body
- causes movement of endolymph that displaces the cupula and bends sensory cells
3.mechanoreceptors generates action potentials in afferent neurons that synapse with the hair cells
depending on direction, in ampulla how do mechanoreceptors generate action potentials?
receptor cell depolarizes and increases
the action potential frequency in the afferent neuron activated by it.
Utricle and saccule are what, and what are their function
fluid-filled chambers 30 degrees to each other
Provide info about:
1) head position (up/down)
2) changes in the rate of
linear motion of the body
How are utricle and saccule membrane different from that of the cupula?
Utricle/saccule membrane contains otoliths; calcium carbonate crystals
How does the utricle and saccule perform its function?
1.head tilt/nonlinear body movement
2.otolithic membrane moves
3.bend hair cells
4. neurotransmitter release
5.action potential
6.brain perceives movement
t/f upright position, otolithic membrane does move.
false, it does not move.
As the position of the head
changes (bend over) gravity causes the otolithic membrane to move.
stereocilia
found on sensory hair cells
Vestibulocochlear nerve
8th cranial nerve
utricle/saccule picks up what two things
linear acceleration and gravity
semicircular canals picks up what thing
angular motion
What part of the vestibular system is
utilized when you nod your head to say
“Yes”?
otolith organs
utricle/saccule
What part of the vestibular system is
utilized when you rotate your head to say
“No”?
semicircular canals
