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Flashcards in Sensory organs Deck (173)
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1

Increasing the amplitude of a stimulus increases...

The frequency of action potentials of the afferent fibres

2

Modality

A particular form of sensory perception

3

Give the classifications of receptors according to: Receptor

  • Primary
  • Secondary
  • Tertiary

4

Give the classifications of receptors according to: Localisation of stimulus

  • Exteroceptors
  • Interoceptors

5

Give the classifications of receptors according to: Form of energy of the stimulus

  • Mechanical
  • Thermal
  • Photo
  • Chemical

6

Give the classifications of receptors according to: Type of perception (modality)

  • Touch
  • Warm
  • Cold
  • Pain
  • Light
  • Sound
  • Taste
  • Smell

7

Give the classifications of receptors according to: Adaptation

  • Fast (Dynamic/phasic)
  • Slow (Tonic/static)

8

Primary receptor

Stimulus elicits a direct conformational change to the channels of the neuron

E.g Olfaction

9

Secondary receptor

Stimulus is sensed by the second cell of sensation, cation channels then open

E.g sound reception: 1. hair cell, 2. auditory nerve

10

Tertiary receptor

Afferent nerve fibre belongs to only the third cell involved in stimulus transduction

E.g 1. Rods + cones, 2. Bipolar cells, 3 Ganglion cells

11

Give the types of receptor

  • Free nerve ending
  • Pacinian corpuscle
  • Golgi tendon organ

12

Give an example of an exteroceptor

Pain/temperature receptors of the skin

13

Pacinian corpuscle

Member of the exteroceptors functioning by no free nerve endings

14

Golgi tendon organ location

  • Found at the border of the tendon and muscle

15

Why are receptors also known as transducers?

Mechanical stimulus may evoke an electric response

16

Generator potential is conducted with...

Decrement/possible information loss

17

Information that has been transformed

  • Travels at a high speed
  • Frequency coded manner
  • Safer

18

Give the temp/AP frequency relationship

19

Title the figure

Skin temp. and AP frequency in various fibres

20

Skin temperature

21

Cold fibre

22

Warm fibre

23

Heat is sensed by what kind of system?

Dual receptor system

  • Warm receptors (receptive between 30-45°C)
  • Cold receptors (receptive between 15-42°C)
  • 2x more cold receptors than warm

 

24

What is unique about olfaction?

  • Fast adaptation to stimuli
  • High differential threshold
  • Difficulty in locating the source

25

What are the receptor cells of the olfactory mucosa?

Bipolar neurons

The only primary receptor cells of higher organisms

26

Describe the receptors of the olfactory mucosa

Receptor cells project cilia into the mucous layer

27

What are the thinnest nerve fibres of the body?

Myelinated axons leaving the olfactory mucosa

28

Primary olfactory neuron

29

Mitral cells

30

Olfactory bulb