Histology - Epithelium

Question 1

Extracellular matrix layer between epithelial cells and underlying CT. Carbohydrate base.

Answer 1

Basement membrane

Question 1

bands encircling the cell, linking adjaent cells together. Resists mechanical separation of cells.

Answer 1

zonula adherens

Question 1

integrin used as adhesive moleculelinking basal lamina to cytoskeleton.

Answer 1

Cell-Matrix Junctions

Question 2

do not normally undergo mitosis, however retains ability if organ damaged or needs increase (ex, hepatocytes).

Answer 2

Stable epithelium

Question 2

bacteria in GI tract that attacks tight junctions and causes ulcers.

Answer 2

Helicobacter pylori

Question 2

Adheren Junctions (Zonula adherens)

Answer 2

E-cadherin (grey dots at TEM) inserted into intracellular space and fuse together and linked to Actin filaments. Zonula (Belt) all the way around the cell. Resist mechanical separation and maintains sheet-like structure. Found in Epithelium and Cardiac muscles

Question 2

Microvilli

Answer 2

Short projections of the apical membrane and cytoplasm of lumen w/ associated Glycocalyx. Composed of plasma membrane surrounding Actin Filament Core which is anchored to a terminal web (actin). Forms a brush border (flat top haircut).

Question 3

Occludin and Claudins

Answer 3

Claudins join in the intercellular space to form Junctional Strands

Question 5

actin filmamentous core, cross linked to plasma membrane and other actin binding proteins. Anchored to Terminal Web (TW) (also actin).

Answer 5

Microvilli core skeleton

Question 7

only a few, no mitosis (adult), eg, cells in core of lens, hair cells, inner ear.

Answer 7

Permananet Epithelium

Question 7

Uncontrolled proliferation of cells (failure of normal regulatory mechanisms)

Answer 7

Neoplasia

Question 8

3-4 longer than MV, less ‘orderly’. Specialized to move substances along a surface.

Answer 8

Cilia

Question 9

steady state renewable, replace cells that are ocntinuously lost, with rpesent stem cells. Proliferation is highly regulated (ex: epidermis, epithelium of GI tract, respiratory system, urogential systems)

Answer 9

Labile epithelium

Question 10

No CAMs, have transmembrane connexons. Aid in cell-cell communication.

Answer 10

Gap junctions

Question 10

tight junction, barrier to paracellular transport.

Answer 10

Zonula Occuldens

Question 11

Lateral Folds

Answer 11

Increases surface area through interdigitation of plasma membrane of adjacent cells, aiding in Fluid and Electrolyte transportation via Transcellular pathway.

Question 12

Focal Adhesion

Answer 12

Integrin proteins linked to basal lamina outside cell and Actin Filaments inside cell. Aids in adhesion and mechanosensitivity.

Question 12

Adaptor Proteins

Answer 12

Supress proliferation of epithelial cells.

Question 14

Transcellular transport

Answer 14

Transcellular transportExchange of substances to/from lumen and CT by passing through an epithelial cell. Active process.

Question 14

associated with aubdant mitochondria that increase surface area for active ion transport.

Answer 14

Basal folds

Question 15

BL (basal lamina) + RL (reticular lamina) (at TEM level)

Answer 15

BM (at light level)

Question 16

a carcinoma featuring microscopic glandular-related tissue cytology, tissue architecture, and/or gland-related molecular products, e.g., mucin.

Answer 16

Adenocarcinoma

Question 17

interact with desmosomes (cell-cell adhesion) and hemidesmosomes (cell-matrix adhesion) via adapter proteins.

Answer 17

Intermediate filaments

Question 17

problem with adhering type junctions, cells pull apart and space fills with fluid.

Answer 17

blistering

Question 19

Covers, lines, secretes, absorbs

Answer 19

Epithelium

Question 20

a cell junction whose cytoplasmic face is linked to the actin cytoskeleton.

Answer 20

Adherens junctions

Question 21

influecne lots of process that occur within cell, one is suppress proliferation (contact inhibition).

Answer 21

adaptor molecules

Question 22

Epithelial cells adjacent to the wound site divide, giving rise to new epithelial cells. The new epithelial cells detach and migrate laterally along the remnants of the basal lamina that are still present.

Answer 22

Wound healing

Question 23

a belt like intercellular junction located between adjacent lateral domains immediately "above" the adherens junction. No CAMs, connected by transmembrane proteins. Help define functional domains (apical-basolateral) - establishing polarity and limit paracellular transport.

Answer 23

tight junction

Question 23

Wound repair

Answer 23

Loss of adaptor proteins causes epithelial cellad and stem cells adjacent ot wound to proliferate. New epithelial cells detach and migrate along basement membrane.

Question 23

Cilia

Answer 23

Long projections used for movement of substances and cells, synchronized movement. Less organized, 9+2 arrangement of microtubules.

Question 24

Cell-to-Matrix Adherents

Answer 24

Hemidesmosomes, Focal Adhesions

Question 25

Apical specilization that establishes extracellular microenvironments at membrane surface. Functions: metabolism, cell regocnition, receptor sites etc. Composed of: glycoproteins and glycolipids.

Answer 25

Glycocalyx

Question 26

orderly series of 3 junctions, tight junction, adherens junction (ZA), desmosome (D) - terminal bar at light level.

Answer 26

Junctional complex (@ TEM)

Question 27

Blisters

Answer 27

Strong abrasionand sheering disrupts Focal Adhesions causing separation of epithelial cells from connective tissue and fluid accumulation.

Question 28

Apical Domain

Answer 28

Directly Contacts Luminal Contents or External Area

Question 30

is an assembly of six proteins that can be a part of a gap junction channel between the cytoplasm of two adjacent cells. Two come together to complete intercellular gap junction channel.

Answer 30

connexon

Question 32

a benign tumor of epithelial tissue with glandular origin, glandular characteristics, or both.

Answer 32

adenoma

Question 33

Interdigitations of plasma membrane of adjacent cell lateral comains located below levelk of the junctional complex that increases surface area for interlocking cells and fluid and electrolyte transport via transcellular pathway.

Answer 33

Lateral Folds

Question 34

Apical Folds

Answer 34

Increase surface area for mainly absorption and secretion between lumen/external environment

Question 35

Integrins

Answer 35

transmembrane receptors that are the bridges for cell-cell and cell-extracellular matrix (ECM) interactions. When triggered, integrins in turn trigger chemical pathways to the interior (signal transduction)

Question 36

Hemidesmosomes

Answer 36

Integrin proteins attached to Basal lamina outside cell and attachment plaque inside cell. Keratin intermediate filaments strengthen them by adhering to attachment plaque. Resists abrasion, sheering, and tearing forces between Epithelial Cells and Basal Lamina. Strong attachment between epithelial cell and basal lamina.

Question 37

Special arrangement of microtubules. 9 outer doublets, and 2 central singlets. Abbreviated "9+2". Anchored into the basal body.

Answer 37

Cilia core

Question 38

Cell-to-Cell Adherents

Answer 38

Adheren Junctions (Zonula adherens), Desmosome (Macula adheren)

Question 39

proteins located on the cell surface involved in binding with other cells or with the extracellular matrix (ECM) in the process called cell adhesion.

Answer 39

Cell adhesion molecules (CAMs)

Question 41

a type of cancer that develops from epithelial cells.

Answer 41

carcinoma

Question 42

Weave back and forth through each cell’s plasma membrane several times

Answer 42

transmembrane proteins

Question 43

9 triplets

Answer 43

Basal body MT composition

Question 45

occludin and claudins that weave through each cell's plasma membrane and extend into ICS.

Answer 45

Transmembrane proteins

Question 47

rows of transmembrane proteins from adjacent cells that appear as ridges or stitches that act as a barrier to paracellular transport pathway.

Answer 47

Junctional strands

Question 48

a type of connective tissue that has a network of reticular fibers, made of type III collagen and only in this lamina are they dominant. Have anchoring fibers and plaques (loops). Thickness varies with frictional force applied to overlying Epi.

Answer 48

reticular lamina

Question 50

directly contacts the luminal contecnts or external environment. Site of absorption and secretion.

Answer 50

Apical domain

Question 51

types of large macromolecular assemblies through which both mechanical force and regulatory signals are transmitted that serve as the mechanical linkages to the ECM, at sites of integrin binding and clustering.

Answer 51

focal adhesions

Question 53

Desmosome (Macula adheren)

Answer 53

Desmosome Cadherin (CAM) insert into intercellular space and overlap each other, inserted into attachment plaque inside cell. Strengthened by keratin intermediate filaments.

Question 54

localized spot-like adhesions randomly arranged on the lateral sides of plasma membranes. help to resist shearing forces and are found in simple and stratified squamous epithelium. 'velcro dots'

Answer 54

desmosome

Question 55

a layer of extracellular matrix secreted by the epithelial cells, on which the epithelium sits. Functions: attachment epithelium to CT, regulation/filtration: exchange b/w E + CT, scaffolding (for regeneration).

Answer 55

basal lamina

Question 56

Tight Junction (Zonula Occludens)

Answer 56

Transmembrane proteins (Occludins and Clausind) weaved back and forth through both cell’s plasma membrane several times that blocks molecular movement between intercellular space. Wrap around cell like a belt. Establishes polarity in cell.

Question 57

Formation of cell/tissue masses as the result of the proliferation of neoplastic cells.

Answer 57

Tumor

Question 59

short, finger-like projections of the apical plasma membrane & cytoplasm into the lumen. Very uniform and itghly packed. Increase SA for absorption (and secretion).

Answer 59

Microvilli

Question 60

Paracellular Transport

Answer 60

Exchange of small solutes, ions, and water between lumen and connective tissue between the lateral domains. Also allows movement of White blood cells into the Connective tissue

Question 61

small stud- or rivet-like structures on the inner basal surface of keratinocytes in the epidermis of skin that attach one cell to the extracellular matrix.

Answer 61

hemidesmosomes

Question 62

zonula adherens, intermediate junction, or "belle desmosome"

Answer 62

Adherens junctions names

Question 63

Exchange of small solutes, ions, and water to/from lumen and CT by pasing netween lateral domains. Passive provess.

Answer 63

Paracellular transport