Unit VIII - Eye Flashcards Preview

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Flashcards in Unit VIII - Eye Deck (108)
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61

What is the area of clearest vision?

Macula lutea

62

What are the only photoreceptors found in the macula lutea?

Cones

63

As we head toward the periphery, we see more of which photoreceptor?

More rods, less cones

64

What kind of photoreceptors do we see on the very edges of our field of vision?

Rods only

65

What is the most anterior primary refractory structure?

Cornea

66

What is the condition of abnormality in the shape of the cornea?

Astigmatism

67

What is the clear fluid secreted by the ciliary processes found on the posterior aspect of the ciliary body?

Aqueous fluid

68

Aqueous fluid is secreted into which chamber of the eye?

Posterior chamber (part of the anterior segment located posterior to the iris)

69

The aqueous humor passes through the pupil into the anterior chamber, travels laterally, and leaves the eyeball through what sinus?

Scleral venous sinus
(Canal of Schlem)

70

What causes glaucoma?

Increased pressure within the anterior segment of the eyeball (can result in blindness)

71

What is unique about the vascular supply to the lens?

AVASCULAR

72

Is the lens convex or concave?

Biconvex

73

Does increasing convexity or increasing concavity of the lens allow for nearer vision?

Increasing convexity

74

What structure separates the anterior segment from the posterior segment?

Lens

75

Which segment of the eye is filled with aqueous humor?

Anterior

76

Which segment of the eye is filled with vitreous humor?

Posterior segment

77

What condition results when the lens gets harder with age and loses its flexibility which can result in more difficult near vision?

Presbyopia

78

What condition results from the lens becoming less transparent?

Cataracts

79

What are the characteristics of the vitreous humor?

Gelatinous and transparent

80

What is the vestigial structure connecting the optic nerve and the posterior aspect of the lens?

Hyaloid canal

81

What artery is contained in the hyaloid canal?

Fetal hyaloid artery

82

In what population does the hyaloid canal serve no functional purpose?

Adults

83

In which direction do tears flow?

Lateral to medial

84

Where are the lacrimal glands located?

Superolaterally to the eyeball

85

What structures carry tears from the lacrimal glands to the surface of the eye?

Excretory ducts

86

Where are the lacrimal ducts found?

In each eyelid below and medial to the eyeball

87

What is the function of the lacrimal ducts?

Drain tears into the lacrimal sac

88

Where is the lacrimal sac found?

In a groove between the lacrimal bone and the maxilla

89

What is the most superior part of the nasolacrimal duct?

Lacrimal sac

90

What structure drains tears from the lacrimal sac into the inferior nasal meatus?

Nasolacrimal duct