Sadilla
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HEY

i was looking at reflex actions of blinking eye and its says that "sensory nerve endings in the cornea detect the stimulus ", but i dont get why that would happen when the sensory neuron has receptor cells at the start of the neuron wouldn't they detected the stimulus ?

thank you would really appreciate the help
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University of East Anglia UG Student Rep
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(Original post by Sadilla)
HEY

i was looking at reflex actions of blinking eye and its says that "sensory nerve endings in the cornea detect the stimulus ", but i dont get why that would happen when the sensory neuron has receptor cells at the start of the neuron wouldn't they detected the stimulus ?

thank you would really appreciate the help
I think you're referring to the corneal reflex in that the stimulus is touching or a foreign body to prevent getting things like dirt in your eye. Therefore the sensory neurone is on the cornea itself.

There is something called an optical reflex as well which is in response to bright lights causing you to blink.
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macpatgh-Sheldon
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Hi,

As UEA Rep says, the stimulus of contact with the cornea is one prompt for the blink reflex (in a more severe situation, the function being protective in order to prevent corneal abrasion). The reason it mentions "sensory nerve endings" is that the sensation produced by anything touching the cornea is pain, and the type of receptors that detect pain are called "free nerve endings". The cornea has a very large concentration of such pain receptors for obvious reasons.

Other types of receptors e.g. Pacinian corpuscles to detect pressure or Meissner's corpuscles, are absent from the cornea in order to maintain transparency.

The cornea consists of five layers, the outermost two being the corneal epithelium and Bowman's layer (the basement membrane of the epithelium), and the free nerve endings actually reach as far externally as the epithelium.

M
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Sadilla
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(Original post by University of East Anglia UG Student Rep)
I think you're referring to the corneal reflex in that the stimulus is touching or a foreign body to prevent getting things like dirt in your eye. Therefore the sensory neurone is on the cornea itself.

There is something called an optical reflex as well which is in response to bright lights causing you to blink.

thank you
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Sadilla
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(Original post by macpatelgh)
Hi,

As UEA Rep says, the stimulus of contact with the cornea is one prompt for the blink reflex (in a more severe situation, the function being protective in order to prevent corneal abrasion). The reason it mentions "sensory nerve endings" is that the sensation produced by anything touching the cornea is pain, and the type of receptors that detect pain are called "free nerve endings". The cornea has a very large concentration of such pain receptors for obvious reasons.

Other types of receptors e.g. Pacinian corpuscles to detect pressure or Meissner's corpuscles, are absent from the cornea in order to maintain transparency.

The cornea consists of five layers, the outermost two being the corneal epithelium and Bowman's layer (the basement membrane of the epithelium), and the free nerve endings actually reach as far externally as the epithelium.

M
thank you soo much
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