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Anatomy And Physiology > Sensory System > Flashcards

Flashcards in Sensory System Deck (81)
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1
Q

What are the two classifications of the senses?

A

General- somatic (body and environment)
-visceral (internal organs)
Special- highly localised receptors

2
Q

What are the 4 kind of information sensory receptors transmit?

A

Modalities (form), location, intensity and duration

3
Q

How can intensity of nerve signals be altered?

A

Alter firing frequency, recruit great number of nerves and use nerve fibres of different thresholds

4
Q

What are phasic receptors?

A

They stop transmitting information even if stimulus continues

5
Q

What do tonic receptors do?

A

Transmit information about the duration of a nerve impulse but they adapt slowly to stimulus

6
Q

What is a receptor?

A

Any structure specialises to detect a stimulus

7
Q

What are the 5 types of receptors?

A

Mechanoreceptors, chemoreceptors, photoreceptors, thermoreceptors and nociceptors

8
Q

What do mechanoreceptors do?

A

They respond to mechanical stimulus such had bending or stretching of cells

9
Q

What do chemoreceptors do?

A

They are membrane receptors that have chemicals become attached to them

10
Q

What are photoreceptors?

A

They respond to light striking a receptor cell

11
Q

What are thermoreceptors?

A

They respond to changes in temperature at site of receptor

12
Q

What do nociceptors respond to?

A

Painful stimuli

13
Q

What are the three major types of unencapsulated sensory nerve endings that are involved in general sensation?

A

Free nerve endings, merkels disc and hair follicle endings

14
Q

What are the 6 major type of encapsulated sensory nerve endings that are involved in general sensation?

A

Meissen corpuscle, Krause end bulb, pacinian corpuscle, ruffini endings, muscle spindle and Golgi tendon.

15
Q

What do meissners corpuscles detect?

A

Touch involved in two-point discrimination

16
Q

What do ruffini endings detect?

A

Continuous touch or pressure

17
Q

What does the pacinian corpuscle detect?

A

Deep pressure, vibration and proprioception

18
Q

What does merkels disks detect?

A

Light, touch and superficial pressure

19
Q

Where on the body are nociceptors not found?

A

The brain

20
Q

Where on the body are nociceptors not found?

A

The brain

21
Q

Where on the body are nociceptors not found?

A

The brain

22
Q

What sort of pain in received from myelinated pain fibres?

A

Fast pain

23
Q

What sort of pain is received from unmyelinated pain fibres?

A

Slow pain

24
Q

What is somatic pain?

A

Pain arising from skin, muscles and joints. It can be superficial (sharp, stabbing and prickly) and deep (less localised and longer lasting)

25
Q

What is visceral pain?

A

Pain arising from the internal organs

26
Q

What are the chemicals injures tissues release that stimulates nociceptors?

A

Bradykinin (from blood protein), serotonin, prostaglandins, histamine and K+

27
Q

What is referred pain?

A

Pain from viscera that is misinterpreted as coming from skin or other superficial structures

28
Q

How does the CNS use to modulate pain?

A

Neuromodulators to block transmission eg. Endorphins or enkephalins or dynorphins

29
Q

What are the sensory inputs we are aware of?

A

Sight, small, sound, touch and taste

30
Q

What are the sensory inputs we are unaware of?

A

Body temperature, blood pressure and muscle tension

31
Q

What is taste a result of?

A

The action of chemicals on the taste buds

32
Q

Where are the taste buds?

A

They lie within the bumps on the tongue as well as on cheeks, soft palate, pharynx and epiglottis

33
Q

What are the 4 types of bumps on the tongue called?

A

Lingual papillae

34
Q

What are the 4 lingual papillae?

A

Filiform, foliate, fungiform and circumvallate

35
Q

What are taste buds made up off?

A

Taste cells, supporting cells and basal cells that differentiate into taste cells

36
Q

What are the 5 primary taste sensations?

A

Salty, sweet, sour, bitter and umami (meaty amino acids)

37
Q

What is the olfactory mucosa?

A

A patch of epithelium made up of smell receptors in roof of nasal cavity

38
Q

What are olfactory cells?

A

Replaceable neurons

39
Q

What are taste cells?

A

Epithelial cells

40
Q

What are the only neurons exposed to the external environment?

A

Olfactory cells

41
Q

What is the life span of olfactory cells?

A

60 days

42
Q

What are the 7 primary classes of odour?

A

Camphoraceous, musky, floral, pepperminty, ethereal, pungent and putrid

43
Q

What is the definition of sight?

A

Perception of objects in an environment by means of the light they emit or reflect

44
Q

What are the accessory structures to the eye?

A

Eyebrows, eyelids, conjunctiva, lacrimal apparatus and extrinsic eye muscles

45
Q

What is the conjunctiva?

A

A vascular, transparent mucous membrane over eye

46
Q

What is the lacrimal apparatus made up of?

A

A gland and duct that drains tears to nasal cavity

47
Q

What does the tear system of the lacrimal apparatus contain?

A

Lacrimal gland, superior lacrimal punctum, superior lacrimal canal, lacrimal sac, inferior lacrimal punctum, inferior lacrimal canal and nasolacrimal canal

48
Q

What are the 3 principal components of the sphere of the eye?

A

Tunica (3 layers that for lm wall), optical apparatus (admits and focuses light) and neural apparatus (retina and optic nerve)

49
Q

What components of the eye is the retina part of?

A

Tunica and neural apparatus

50
Q

What components of the eye is the cornea part of?

A

Tunica and optical apparatus

51
Q

What are the 3 parts that make up the tunica?

A

Tunica fibrosis, tunica vasculosa and tunica interna

52
Q

What is the tunica fibrosis made up of?

A

Sclera (white of eye) and cornea

53
Q

What is the tunica vasculosa made up of?

A

Choroid (highly vascular, deeply pigmented layer behind retina), ciliary body (think extension of choroid forming muscular ring around lens) and iris

54
Q

What determines your eye colour?

A

Amount of melanin

55
Q

What is the tunica interna made up of?

A

Retina

56
Q

What parts of the eye are that transparent elements that admit, bend and focus light?

A

Cornea, aqueous humour, lens and vitreous body

57
Q

What is the retina?

A

A thin transparent membrane that is attached at the optic disc and ora serrata

58
Q

Where is the macula lutea?

A

Directly posterior to centre of lens

59
Q

What does the macula lutea do?

A

It is responsible for sharp, finely detailed images as it has a high concentration of cones and no rods

60
Q

What is the optic disc?

A

The blind spot where all nerves and blood vessels pass

61
Q

What happens in proliferative diabetic retinopathy?

A

Irregular new blood vessels are formed

62
Q

What are pupillary constrictors?

A

Concentric circles of SMC that narrow pupil

63
Q

What are pupillary dilators?

A

Spokelike myoepithelial cells that widen pupils

64
Q

How is light bent in the eye?

A

By curvature of cornea towards centre of retina

65
Q

What is the refractive index?

A

Measure of bending of a ray of light as it travels through different mediums of eye

66
Q

What is the near response?

A

Eyes adjustment to close range vision

67
Q

What are the 3 processes involved in the near response to focus an image on the retina?

A

Convergence of eyes, constriction of pupil and accommodation of lens

68
Q

What is the closest an object can be at age 10 and 60 that can still be in focus?

A

7cm and 100cm

69
Q

What lens would you use for someone with hyperopia (far sighted)?

A

Convex lense as uncorrected image is projected too far behind eye ball

70
Q

What lens would you use for someone with myopia (short sighted)?

A

Concave lens because uncorrected eye projects image short of where it needs to be in eye ball

71
Q

What are the 5 cellular layers of the eye?

A

Pigment cell layer, photoreceptor layer, bipolar layer, ganglion layer and nerve fibre layer

72
Q

What is the pigment cell layer of the eye?

A

Retinal layer that absorbs light and reduces light scatter

73
Q

What is found in the photoreceptor layer of eye?

A

Rods on the periphery of the eye that help see at night and cones in the centre of the eye that help see in the day and see colour

74
Q

What cellular layer has largest neurons of retina?

A

Ganglion layer

75
Q

What is the visual pigment in rods?

A

Rhodopsin (retinal and opsin)

76
Q

What is the visual pigment found in cones?

A

Photopsin (retinal and a bit opsin)

77
Q

Is retinal a pigment or a protein?

A

Pigment

78
Q

Is opsin a pigment or a protein?

A

Protein

79
Q

At what wavelength is blue light absorbed?

A

420nm

80
Q

At what wavelength is green light absorbed?

A

534nm

81
Q

At what wavelength is red light absorbed?

A

564nm