Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

OPTM 5032 - Ocular Physiology > Lacrimal Glands and Conjunctiva > Flashcards

Lacrimal Glands and Conjunctiva Flashcards

1
Q

What is the function of the Main Lacrimal Gland

A

Primary provider of the aqueous secretory component to the tear film

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where is the lacrimal gland located?

A

In the fossa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the two lobes of the lacrimal gland?

A

Orbital (larger/ above) and Palbebral (below)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Where is the lacrimal gland divided?

A

Divided by the lateral horn of the levator and extensions of the Müller’s muscle into an orbital lobe and palpebral lobe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the color of the lacrimal gland?

A

pinkish gray

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the lacrimal gland surrounded by?

A

Connective Tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the lacrimal gland made up of?

A

many acini that drain into progressively larger tubules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are acini made up of?

A

A basal myoepithelial cell layer with inner columnar secretory cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Because of the acini, the lacrimal gland requires _____ movement to allow the contents to be drained

A

muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

When does the lacrimal gland start developing?

A

Third month of fetal life but not functional until after birth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

When do newborns begin to produce tears?

A

2 weeks - 2 months

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the function of the accessory lacrimal glands?

A

Secondary provider of the aqueous secretory component to the tear film

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the names of the accessory lacrimal glands?

A

Glands of Krause and Wolfring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where is the gland of Wolfring located?

A

In the tarsal plate of the eyelid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Where are there few accessory glands (lower or upper eyelid)?

A

Lower eyelid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What type of secretion comes from the Gland of Wolfring?

A

Serous which forms the middle portion of trilaminar tears

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Where is the Conjunctival Lacrimal Gland of Krause located?

A

In the conjunctival fornix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which contributes more: Gland of Krause or Lacrimal Gland?

A

Lacrimal Gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Where does the arterial supply of the lacrimal gland come from?

A

The lacrimal branch of the ophthalmic artery

A branch of the infraorbital artery

The recurrent meningeal artery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Which nerve carries the sensory stimuli from the lacrimal gland?

A

The lacrimal branch of the trigeminal nerve (CN V)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What does the tear film cover?

A

The ocular surface (cornea and conjunctiva)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the three layers of the tear film?

A

Outer lipid layer

Middle aqueous layer

Inner mucous layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the function of the tear film?

A
  1. Primary source of oxygen to cornea
  2. Lubricant between lids and ocular surface
  3. Movement of tears removes foreign bodies,
  4. Contain antibacterial proteins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Is the cornea vascular or avascular?

A

Avascular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Which glands secrete the lipid layer?

A

Sebaceous glands

Meibomian gland

Sebaceous gland of Zeiss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Which glands produce the aqueous layer?

A

Serous glands

Lacrimal gland

Fornix accessory lacrimal gland

Palbebral accessory lacrimal gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Which glands secrete the mucous layer?

A

Goblet cells

Epithelial cells

Lacrimal gland (very little)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How thick are each of the layers in tears?

A

Lipid - 0.1 microns

Aqueous - 7 microns

Mucous - 0.02 to 0.05 microns

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Holocrine secretion

A

When the discharged secretion contains the entire secreting cells laden with the secretary material

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What does the blink do?

A

The blink releases the meibomian material from the ducts onto the tears

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What do the sebaceous glands do?

A

Secrete lipids onto the tear film (wax monoesters, sterol esters, hydrocarbons, triglycerides, diglycerides, free sterols (including cholesterol), free fatty acids, and polar lipids (including phospholipids)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Two possible steps where regulation could occur in the meibomian?

A
  1. Controlling the rate of lipid synthesis in the ER
  2. Regulating the rupture of alveolar cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

In terms of regulation in the meibomian gland what would androgen sex steroids or testosterone do?

A

May regulate synthesis and secretion

Testosterone - females

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

In terms of regulation in the meibomian gland what would neurotransmitters do?

A

Alter synthesis or rupture of cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Neural regulation of the Meibomian Gland would be controlled by?

A

Vasoactive intestinal peptide (VIP) neuropeptide (NPY)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What do normal lacrimal glands do?

A

Keep ocular surface moist, well lubricated, free of mechanical and chemical irritants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Two levels of tear secretion?

A

Low order secretion during normal activities

High order secretion during reflex tearing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What does the lacrimal gland secrete?

A

Nutrients, growth factors, immunoglobulins in N+, K+-, and CL– rich solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

The final tear film is a mixture is?

A

NaCl-rich

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

The main lacrimal gland is a lubuloacinar exocrine that secretes?

A

Proteins

Electrolytes

Water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

The proteins secreted by the lacrimal glands are?

A

Lysozyme

Lactoferrin

Lipocalin

(SIgA), epidermal growth factor, (TGFs), and interleukins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Conjunctival CL- secretion into tears accounts for what percentage of active transport of the conjunctiva

A

60-70%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

The primary source in mucous layer is?

A

Goblit cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What do mucins contain?

A

Glycoproteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What are glycoproteins?

A

protein backbone with carbohydrate side chains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What type of glycoproteins are in the mucous layer?

A

Large heterogenous glycoproteins (at least 50% carbohydrate by mass)

47
Q

Secretion of the mucous layer happens because of

A

activation of the sensory nerves

48
Q

What is the secondary type of cell secreted by the mucous layer?

A

Stratified Squamous Cells of conjunctiva and corneal epithelia

49
Q

What is the punctum?

A

Opening on the medial portion of each eyelid

50
Q

What are the superior and inferior canaliculu lined with and surrounded by?

A

Lined with stratified squamous epithelium

Surrounded by the orbicularis muscle

51
Q

How large are the puncta?

A

0.3 mm

52
Q

How big are the canaliculi?

A

10 mm in length

0.5 to 1.00 mm in diameter

53
Q

How commonly is the common canaliculus found?

A

Formed in 90% of individuals from superior and inferior canaliculi

54
Q

How much of the tear volume is lost to evaporation?

A

10-25%

55
Q

After evaporation, where are remaining tears drained?

A

Through the lacrimal system into the nose

Some may be absorbed into the nasolacrimal system

56
Q

There are ___ times as many tears that drain through the inferior punctum compared to the superior punctum because of gravity

A

4 times

57
Q

What are two things necessary of tears for optimal visual function?

A

Adequate secretion and drainage of tears

58
Q

What is the lacrimal pump theory?

A

contraction of the pretarsal orbicularis muscle fibers during eyelid closure compresses and shortens the canaliculi

59
Q

The consistent problem of epiphora in the setting of facial paralysis is that it?

A

underscores the important contribution of the orbicularis muscle to lacrimal outflow.

60
Q

Volume of tears drained per blink

A

2.0 ml

61
Q

1 blink transports more tears than ____ min(s) of basic secretion

A

1

62
Q

The lacrimal excretory system usually functions far (above or below) capacity

A

below

63
Q

When does the siphoning by the lacrimal sac occur?

A

During relaxation not during closure

64
Q

gravity (increases or decreases) lacrimal drainage

A

increases

65
Q

What are some situations that lead to an insufficient tear layer?

A

Atrophy of lacrimal gland

Increase in age

Compromised innervation

66
Q

Causes of dry eye complaints in contact lens wearers

A
  1. Insufficient tears
  2. poor tear quality
  3. infrequent blinking
  4. incomplete blinking
  5. reflex tears have low osmolarity
  6. poor contact lens wetting
  7. Blepharitis
67
Q

Normal tear production varies with ____ but not ____

A

age

gender

68
Q

Normal result of schirmer’s test

A

Greater then or equal to 15 mm wetting of paper have 5 minutes

69
Q

Mild dry eye result of schirmer’s test?

A

14-9 mm wetting of paper after 5 minutes

70
Q

Moderate dry result of schirmer’s test?

A

8-4 mm wetting of the paper after 5 minutes

71
Q

Severe dry eye result of schirmer’s test?

A

<4 mm wetting of the paper after 5 minutes

72
Q

Acinar cells secrete fluid having an _____ composition similar to that of plasma

A

electrolyte

73
Q

What is acinar cell electrolyte secretion driven by?

A

Na+K--ATPase pumping Na+ out of the cell and K+ into the cell

74
Q

As the flow rate of the acinar cells increases the fluid goes from _____ to _____

A

hypertonic

isotonic

75
Q

How do ductal cells modify the fluid secreted by the acinar cells?

A

By secreting a fluid that is rich in KCl

76
Q

The lacrimal gland is innervated by?

A

Parasympathetic nerves

sympathetic nerves

sensory nerves

77
Q

Lacrimal gland secretion is regulated by?

A

The nerves that innervate the secretory cells and by the peptide and steroid hormones present in the blood that stimulate secretion

78
Q

Stimulation of the sympathetic nervous system results in what kind of change in tear secretion?

A

No Change

79
Q

parasympathetic fibers of which nerve are responsible for secretion

A

CN 7

80
Q

What is the main contributor to tear film?

A

parasympathetic fibers

81
Q

What can cause stimulation of lacrimal gland secretion?

A

Sensory nerves at optic surface

bright light hitting the optic nerve

acetylcholine and vasoactive intestinal peptide (VIP)

Norepinephrine

82
Q

Conjuctiva provides passage for?

A

The secretion produced by the lacrimal gland and accessory lacrimal glands

83
Q

What is the most immunologically active tissue of the external eye?

A

Conjunctiva

84
Q

The normal conjunctival epithelium contain _____ neutrophils and _____ lymphocytes

A

6,000

14,000

85
Q

Conjunctival reactions can be provoked by ____, ____, and ____

A

infections

allergies

inflammation

86
Q

Reactions are characterized by two structural changes

A

papillae formation

follicle formation

87
Q

Papillae are found in areas of conjunctival _____

A

hypertrophy

88
Q

What do papillae contain?

A

eosinophils and neutrophils

89
Q

How are papillae distinguished from follicles?

A

By the presence of blood vessels in their centers

90
Q

Which lid are papillae most commonly found?

A

The upper lid

91
Q

What are follicles?

A

clear, fluid-filled pockets containing lymphocytes and macrophages

have blood vessels passing either above or below, never within

92
Q

_____ and ____ are not found in normal conjunctival epithelium (only in epithelium of what two disease?)

A

eosiniphils

basophils

vernal conjunctivitis

giant papillary conjunctivitis

93
Q

When a contact lens has dislocated from the corna and is not visible it is most likely found where?

A

in the superior fornix since it has the greatest depth

94
Q

What are the layers of the conjunctiva?

A

epithelium

stroma

95
Q

Where are the palisades of vogt found?

A

immediately peripheral to the limbus

96
Q

What is the role of the palisades of vogt?

A

The limbal stem cells reserve

(continually contribute cells to cornea and serve as reserve source in the event of trauma)

97
Q

What are globlet cells and how wide are they?

A

unicellular mucin-secreting glands (holocrine) within conjuctival epithelium

11 microns wide on average

98
Q

Where are the goblet cells found most frequently?

A

In the fornix and palpebral conjunctiva

99
Q

The stroma is made up of a rich network of _____

A

capillaries

100
Q

What is the rich supply of nutrition needed for in the stroma?

A

Needed for regenetation of the epithelium and formation of new goblet cells

101
Q

Where are mast cells found?

A

in the adenoid layer of the conjunctival stroma along with other inflammatory cells

102
Q

The mast cells are extremely numerous in conjunctival stroma with ______ cells per cubic mm

A

6,000

103
Q

Mast cells are responsible for the _____ ______ reaction

A

immediate

hypersensitivity

104
Q

What is the cytoplasm of mast cells filled by?

A

30 - 100 metachromatic granules

105
Q

What do mast cells contain?

A

several preformed chemical mediators of inflammation

histamine and heparin

106
Q

dramatic changes occur in mast cells membrane and cytoplasm when mast cells are bound by?

A

IgE

107
Q

Physical properties change in mast cells so that the membrane becomes more permeable to what ions? This leads to?

A

Ca++

Edema and swelling of the conjunctiva

108
Q

in infections of the conjunctiva ____ ____ ____ are engorded

A

superficial posterior vessels

109
Q

What is keratitis?

A

inflammation of the cornea

110
Q

What is iritis?

A

Inflammation of the iris

111
Q

In keratitis and iritis what are engorged and what color are they?

A

Deep ciliary vessels

bright red/purple hue

112
Q

Are there lymphatics within the globe?

A

No

113
Q

The flow of the lymph is fenerally in the _____ direction toward the ______ extremes of the lid

A

temporal

lateral

114
Q

The conjunctiva is richly supplied by what?

A

lymphatics

OPTM 5032 - Ocular Physiology (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions