Epithelial Tissue and Glands 8-29 Flashcards

1
Q

4 tissue types

A

Epithelial, connective, muscular, nervous - extracellular material typically created by these cells.

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

Epithelial tissue categories

A

Covering/Lining, Glandular epithelium

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

Epithelial tissue functions

A

Secretion - glands (stomach columnar epithelium, goblet)
Absorption - intestines
Filtration
Excretion
Transport - cilia can move mucous.
Protection - epidermis - skin is an example, transitional epithelium protects urinary gland so that urine doesn’t go backwards.

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

Epithelial tissue characteristics

A

Cellularity - lots of cells in tissue bonded closely. Bound by adhesion molecules, form specialized cell junctions.
Specialized Contacts - transport outside and inside.
Polarity - free apical surface to external environment (lumen, etc.) modifications exist here, basal surface
-free or apical surface/pole/domain
-lateral surface/domain - cells in close contact (see junctions here)
-basal surface/pole/domain - epithelium comes in close contact with connective tissue.
Supported by Connective Tissue – lamina propria:
Avascular, but Innervated - connective tissue has blood vessels to supply.
Regeneration

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

Cell layer types

A
  1. Simple
    2) Stratified
    3) Pseudostratified - simple but look stratified (nuclei are the tell)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Cell shapes

A

Squamous, cuboidal, columnar - taller than wide, elongated nucleus toward basal side usually - mostly non-ciliated form
.

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

Additional cell names

A

Based on specialization on apical cell surface (ciliated) or apical tissue surface (keratinized)

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

Urothelium

A

Transitional epithelium - surface cells are umbrella cells. When organ is empty (urinary bladder, ureters, urethra), wall is not distended. Wall stretches as organ fills, surface cells change shape (umbrella to squamous).

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

Two Types of Stratified Squamous Epithelium

A

Nonkeratinized Stratified Squamous Epithelium

Keratinized Stratified Squamous Epithelium

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

Domains of epithelial cells

A

Apical domain
Lateral domain
Basal domain

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

Microvilli

A

Cytoplasmic extension/processes with core of actin filaments. 1 microm high, Average width: 0.08µm
Creating striated border (intestinal epithelium) or brush border (kidney tubule cells)
Function: increase surface area

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

Stereocilia

A

Considered long microvilli

Function: increase surface area

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

Cilia

A

movement, rapid back and forth motion. 5-10 microm in length, 0.2 microm in width. Contains an axoneme, The microtubules insert into basal bodies

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

Junctional complex parts

A

Zonula Occludens or Tight Junctions
Zonula Adherens
Macula Adherens or Desmosomes

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

Zonula occludens

A
Tight junction - type of occluding junction
found closest to apical surface
transmembrane proteins (occludins and claudins) fuse outer surfaces of adjacent membranes together sealing off the intercellular space
forms a continuous band around the cell which is impermeable, thus it limits the movement of substances between luminal space and tissue compartments via the intercellular space
diffusion barrier between cells 
gives the “barrier” characteristic to epithelial tissue; for items to get across now they must be actively transported via the specialized membrane proteins of epithelial cells
also prevents integral membrane proteins movement between domains
provide only limited resistance to mechanical stresses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Zonula adherens

A

a type of anchoring junction
provide mechanical stability by linking cytoskeleton of one cell to the cytoskeleton of the next; great for resisting separation
forms a continuous band around the cell
microfilaments (actin) of the first cell attach to a plaque on the inside of its plasma membrane; this plaque is attached to transmembrane protein (cadherin) which crosses the plasma membrane of the first cell and attaches to the cadherin of an adjacent cell; this second cell’s cadherin crosses its plasma membrane where it attaches to a plaque just on the inside of the plasma membrane; this plaque is attached to the microfilaments (actin) of the second cell; thus connecting cytoskeleton of one cell to the next.

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

Macula adherens

A

Desmosome - a type of anchoring junction
provide mechanical stability by linking cytoskeleton of one cell to the cytoskeleton of the next; great for resisting separation
forms spot welds; not continuous around cell; localized
intermediate filaments of the first cell attach to a plaque on the inside of its plasma membrane; this plaque is attached to transmembrane protein (cadherin) which crosses the plasma membrane of the first cell and attaches to the cadherin of an adjacent cell; this second cell’s cadherin crosses its plasma membrane where it attaches to a plaque just on the inside of the plasma membrane; this plaque is attached to the intermediate filaments of the second cell; thus connecting cytoskeleton of one cell to the next.

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

Gap junctions

A

these are communicating junctions
transmembrane proteins are in the form of a protein tunnel called a connexon
the connexon of one cell lines up with the connexon of the next cell allowing the cells to exchange ions and small molecules; these items can diffuse from the cytosol of one cell to the cytosol of the next.
allows communication between cells; this is especially important in tissues were the activity of the cells need to be coordinated.

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

Basal lamina components

A

Lamina lucida, lamina densa

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

Focal Adhesions

A

a type of anchoring junction
looks somewhat similar to a zonula adherens junction, but it doesn’t link adjacent cells
links the cell to the basal lamina; specifically it anchors microfilaments (actin) of the cytoskeleton of a cell to the basal lamina
actin filaments are attached to extracellular matrix glycoproteins (ex. laminin and fibronectin) in the basal lamina via integrins (the transmembrane protein used here)
functional role in signal detection and transmitting signals from the extracellular environment into the interior of the cell; mechanosensitivity

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

Hemidesmosome

A

a type of anchoring junction
looks somewhat similar to a desmosome, but it doesn’t link adjacent cells
links the cell to the basal lamina; specifically it anchors intermediate filaments of the cytoskeleton to the basal lamina
intermediate filaments are attached to laminin and type IV collagen in the basal lamina via integrins (the transmembrane protein used here)
found in epithelia subject to abrasion and mechanical shearing forces; useful for keeping the epithelium from separating from the underlying connective tissue

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

Gland types

A

Relation to surface - endocrine and exocrine

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

Endocrine gland

A

ductless glands; secrete into interstitial fluid, release hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Exocrine gland

A

secrete their products onto a surface either directly or via an epithelial duct.

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

Endocrine gland hormones

A

Circulatory Hormones
Paracrine Hormones
Autocrine Hormones

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

Exocrine gland classificating traits

A

Cellularity
Structure/Morphology
Type of Secretion
Mode/Mechanism of Secretion

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

Cellularity (exocrine)

A

can be classified based on the number of cells that compose the gland - Unicellular Exocrine Glands – one cell
Multicellular Exocrine Glands – more than one cell; consists of a cluster of cells.

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

Goblet cells

A

Intestinal epithelium - produce and secrete mucin - also in epithelial lining of respiratory tract. Nucleus like a wine glass (almost triangular).

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

Structure/morphology exocrine

A

Structure of Duct
Simple – unbranched
Compound – two or more branches
Structure of Secretory Units*
Tubular – tube shaped; either short or long and coiled
Alveolar or Acinar – round or globular
Tubuloalveolar and Tubuloacinar – combination

*Note: These secretory units can be branched or unbranched; they also may be coiled.

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

Simple duct structure

A

Duct does not branch

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

Compound duct structure

A

Duct branches

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

Secretion - exocrine

A

Mucous Glands
Serous Glands
Mixed Glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Serous cells

A

Polarized, protein-secreting cells
Typically produce digestive enzymes and other proteins
Pyramidal in shape – broad base on basal lamina and narrow apical surface facing lumen
Contain secretory granules called zymogen granules – spherical in shape; found in apical cytoplasm
Basophilic cytoplasm due to RER and free ribosomes
Nuclei are rounded

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

Mucous cells

A

Produce hydrophilic glycoprotein mucins
Cuboidal or columnar in shape
Flattened nuclei at base of cells
Contain secretory granules called mucinogen granules – found in apical cytoplasm; PAS positive

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

Myoepithelial cells

A

Found within the basal lamina of secretory units and the initial part of duct system
Can contract; accelerates secretion of the product
Also prevent distention of area when lumen fills

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

Salivon

A

Basic unit of salivary gland. composed of the acinus and all related ducts.

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

Acinus

A

is a blind sac composed of secretory cells and is the secretory portion. Three secretory acini are found in salivary glands

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

3 acini in salivary glands

A

Serous Acini, Mucous Acini Mixed Acini

39
Q

Serous acini

A

serous cells only; generally spherical shaped

40
Q

Mucous acini

A

mucous cells only; generally tubular shaped

41
Q

Mixed acini

A

contain both serous and mucous cells; in traditional fixation methods it appears the mucous acini have a cap of serous cells; these caps are called serous demilunes; found in the sublingual and submandibular glands

42
Q

Serous demilunes

A

Cap of serous cells on mucous acini.

43
Q

Types of exocrine glands based on secretion mode

A

Merocrine Glands
Holocrine Glands
Apocrine Glands

44
Q

Muscular tissue

A

moderate amount of EC matrix

45
Q

Nervous tissue

A

Detect stimuli, react via action potentials. Lots of cells with intertwining processes, little to no EC material.

46
Q

lamina propria

A

Connective tissue associated with mucous membranes (wet).

47
Q

Basement membrane

A

Secreted by epithelial tissue and includes connective tissue below.

48
Q

Naming for stratified epithelium

A

Look at surface cells only.

49
Q

Umbrella cells

A

Transitional epithelium - top layer “squishy” non-distended = rounded shape.

50
Q

Naming *Squamous

A

Keratinized or nonkeratinized - skin is where you see keratinized most. Nonkeratinized shows up in esophagus, vagina.

51
Q

Columnar Naming

A

Ciliated, nonciliated. Most simple columnar is non-ciliated. See most of this in stomach, small intestine and large intestine. Since most is non-ciliated, nonciliated term usually dropped.

52
Q

Pseudostratified naming

A

Almost all have cilia.

53
Q

Simple protection

A

Most do not offer protection, usually there for exchange (especially squamous).

54
Q

Serous membrane

A

Covers peritoneal cavity/organs

55
Q

Bowman’s Capsule

A

Simple squamous - nuclei bulge.

56
Q

2 places where simple squamous changes names

A

Mesothelial lining of peritoneum Mesothelium. Endothelium - lines arterioles and heart.

57
Q

Mesothelium

A

simple squamous membrane associated with thoracic cavity check this

58
Q

Endothelium

A

Simple squamous associated with blood vessels/lining heart. Cells in the direction of bloodflow (reduce resistance within blood vessels).

59
Q

Simple cuboidal

A

Secretion, absorption, infiltration, excretion. Kidney tubules, ducts (a lot are with this), small glands, ovary surface.

60
Q

Simple columnar

A

Goblet cells in these tissues, absorption, secretion of mucous, produce enzymes/substances. Some are ciliated to propel mucous or reproductive cell ciliary action. Most of the digestive tract is this. Ciliated columnar line bronchi. **NOTE distinguish between microvilli and cilia. Microvilli are much shorter.

61
Q

Duct cell type

A

Change as ducts go out - some have simple columnar to stratified.

62
Q

Slide 26

A

*

63
Q

Stratified squamous

A

If you see nuclei at surface (alive), nonkeratinized.

64
Q

Stratified cuboidal

A

Very rare - find in sweat glands, a few esophogeal glands, part of male urethra, etc.

65
Q

Stratified columnar

A

Taller than wide, very rare. Lines part of urethra, large excretory ducts, etc.

66
Q

Pseudostratified columnar

A

Goblet cells usually associated with it, can be associated with cilia (usually is). Find this lining the majority of the respiratory tract. Respiratory epithelium = ciliated pseudostratified columnar epithelium.

67
Q

Trachea

A

has thickest basement membrane of whole body.

68
Q

Slide 34

A

View slide images

69
Q

Review all scope slides

A

**

70
Q

Polarity

A

Surface and organelle location - cellular junctions keep certain membrane proteins on one surface.

71
Q

Striated border

A

Layer of microvilli creating striated border. Intestines.

72
Q

Brush border

A

Striated border in kidney.

73
Q

Microvilli

A

20-30 actin filaments cross linked to each other. Ties into terminal web (more actin filaments) to secure it. Myosin helps tie the actin to PM, but no movement.

74
Q

Cilia vs microvilli

A

Grouped and clumped and longer than microvilli. Microvilli in an even layer.

75
Q

Stereocilia

A

Long microvilli - Does not move. Just more surface area. In epidydimus, associated with sensory cells of inner ear. Core is the same 20-30 actin filaments into terminal web.

76
Q

Cilia

A

Move, longer and wider than microvilli. Respiratory tract, oviducts. Move fluid or particulate matter along apical surface. Tie in to basal bodies (darker at surface, more sporadic). Shorter than flagella

77
Q

Terminal bars

A

Junctional complex - no cement, represent junctional complex - numerous cell junctions.

78
Q

Zonula occludens

A

Goes whole way around cells. Tight junction, occluding junction. Transmembrane proteins link one cell to the next. Creates a diffusion barrier, nothing gets between cells. Must cross plasma membrane. Limits movement of transmembrane proteins in plasma membrane as well. Sets PM domains, not good for mechanical resistance.

79
Q

Zonula

A

Wrapping whole way around a cell. Ties cytoskeleton (actin) of once cell to another.

80
Q

Macula adherens

A

Intermediate filaments tie to plaques this time (see 3)

81
Q

Connexon

A

Transmembrane protein (6 connexins). Connexon of 1 cell lines up with the connexon of the next. Connexins change shape to open or close a channel. Connects cytosol to cytosol.

82
Q

Basement membrane

A

Basal lamina and reticular lamina. Only with LM

83
Q

PAS Stain

A

Periodic acid schiff stain. Looks for sugars, shows basement membrane. Breaks down glycogen

84
Q

Basal lamina

A

Lamina lucida (transparent artifact), lamina densa. Using osmium tetroxide you can see this. Use this term for EM.

85
Q

Glandular epithelium

A

Proliferation of cells into connective tissue. Cells can synth, store, release complexes. Often store product in secretory granules.

86
Q

Endocrine

A

Stuff picked up from EC to cardiovascular system (thyroid, pituitary, adrenal)

87
Q

Circulatory

A

Picked up by cardiovascular system. Only cells w/receptors can respond. Extremely common.

88
Q

Paracrine

A

Interstitial fluid, binds to adjacent cells.

89
Q

Autocrine

A

Binds to self to affect activity.

90
Q

Goblet

A

Unicellular exocrine gland.

91
Q

Conventional fixation amend

A

Mucogen granules pass serous cells out**

92
Q

Merocrine

A

Exocytosis - most common form of secretion

93
Q

Holocrine

A

Rupture - sevaceous glands of skin

94
Q

Apocrine

A

Cytoplasm, PM, product. Debatable if in humans. Basically cell losing it’s top. Closest example is mammary glands… but no cytoplasm.