Sensory Receptors 1 Flashcards Preview

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Flashcards in Sensory Receptors 1 Deck (20)
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1
Q

Define sensory receptors.

A

Nerve endings, often with specialised non-neural structures.

2
Q

Define sensory modality.

A

A type of stimulus activating a particular response.

3
Q

Define adequate stimulus.

A

The type of energy a receptor responds to.

4
Q

Define sensory receptors.

A

Highly sensitive to one specific energy but can be activated by other energies.

5
Q

Define mechanoreceptors.

A

Stimulated by mechanical stimuli i.e pressure.

6
Q

Define proprioceptors.

A

Mechanoreceptors in joints and muscles that signal information related to body or limb position.

7
Q

Define nociceptors.

A

Respond to pain stimuli.

8
Q

Define thermoreceptors.

A

Detect cold and warmth.

9
Q

Define chemoreceptors.

A

Detect chemical changes.

10
Q

Define photoreceptors.

A

Respond to particular wavelengths of light.

11
Q

What does transduction involve in all sensory receptors?

A

Opening and closing of ion channels.

12
Q

Adequate stimulus causes a ______ potential change which is membrane ______.

A

Grade, deformation.

13
Q

What is frequency coding of stimulus intensity?

A

When a larger stimulus gives a larger receptor potential and therefore increases frequency of action potentials in a sensory nerve.

14
Q

Define pacinian corpuscle.

A

A myelinated nerve with a naked nerve ending, enclosed by a connective tissue capsule of layered membrane lamellae.

15
Q

When do pacinian corpuscles respond?

A

When a mechanical stimulus deforms the capsule and nerve ending.

16
Q

What activates a somatic sensory neuron?

A

Stimuli in a specific area (receptive field).

17
Q

Sensory neurons with neighbouring receptive fields exhibit ______ ______.

A

Neuronal convergence.

18
Q

What does convergence allow?

A

Simultaneous sub-threshold stimuli to sum at the secondary neuron, initiating action potentials.

19
Q

Define activity.

A

The ability to locate a stimulus on the skin and differentiate it from another closeby.

20
Q

What does lateral inhibition help with?

A

The precision of knowing where the skin is being touched.