Epithelial Tissues

Front 1

Tissue

Back 1

A group of closely associated cells (and their extracellular products) that perform related functions and are similar in structure.

Front 2

4 Types of Tissues

Back 2

1. Connective

2. Epithelial

3. Muscular

4. Nervous

Front 3

Cell Junctions

Back 3

- Point of contact between cells.

- Holds cells together in different ways.

Front 4

Epithelial Tissue Arrangement/Structure

Back 4

- Cells are densely packed, arranged in sheets

- Many cell junctions are present

- Epithelial is avascular but is innervated

Front 5

Epithelial Tissue Location/function

Back 5

- Epithelial cells attach to a basement membrane - generally found on surfaces and sit on top of other tissues.

- Used to cover and line free surfaces, and forms most glands(bundled up sheets)

Front 6

What occurs frequently in epithelial tissue?

Back 6

Mitosis - has a fast regeneration rate.

Front 7

General Functions of Epithelial Tissue

Back 7

- Protection

- Diffusion

- Absorption, secretion, and ion transport

- Filtration

- Forms slippery surfaces

Front 8

Epithelial - Diffusion Example

Back 8

gases in and out of blood

Front 9

Epithelial - Absorption/Secretion/Ion Transport Example

Back 9

- epithelial layer in mucous and serous membrane, absorb chemicals

Front 10

Epithelial - Filtration Example

Back 10

Urinary system built with epithelial tissue

Front 11

Special Characteristics of Epithelia

Back 11

- Cellularity

- Polarity

Front 12

Cellularity

Back 12

Cells separated by minimal extracellular material

Front 13

Polarity

Back 13

Cell regions of the apical surface differ from the basal surface

Front 14

Apical

Back 14

Air (free surface)

Front 15

Basal

Back 15

Bottom

Front 16

How do you classify epithelial tissue?

Back 16

- classified according to the shape of the cells and how many layers thick they are.

Front 17

The name of the specific type of stratified epithelial tissue depends on...

Back 17

...the shape of the apical cells

Front 18

Arrangement of Layers (epithelial)

Back 18

- Simple

- Stratified

- Pseudostratified

Front 19

Simple

Back 19

- Single Layer

- Every cell in tissue touches the basement membrane

Front 20

Stratified

Back 20

- More than 1 layer

- Some cells never touch the basement membrane

Front 21

Pseudostratified

Back 21

- Every cell touches the basement membrane even if it doesn't look like it.

Front 22

Pseudo-

Back 22

False

Front 23

Cell Shape (epithelial)

Back 23

- Squamous (cells are squished/flat)

- Cuboidal

- Columnar

Front 24

Glandular Epithelium

Back 24

A gland is a single cell or a mass of epithelial cells adapted for secretion

- Exocrine and Endocrine glands

Front 25

Endocrine Glands

Back 25

- Group of epithelial cells that make hormones→boodstream

- No ducts

Front 26

Epithelial - Forms Slippery Surface (Example)

Back 26

- Epithelial tissue in serous membrane allows for organs to slide easily

Front 27

Basement Membrane

Back 27

non-cellular structure that holds epithelial and connective tissue together (the glue)

Front 28

Simple

Back 28

only one layer

Front 29

Cuboidal

Back 29

Cells are roughly square shaped with centrally located nuclei

Front 30

Squamous

Back 30

Cells are flat and squashed

Front 31

Columnar

Back 31

Cells are long and thin(column shaped) with nuclei that are near the basal surface

Front 32

Pseudostratified

Back 32

Tissues appears to be stratified, but is simple.

Front 33

Transitional Epithelium

Back 33

Always stratified, and cells on the apical surface can change from a dome-like cuboidal shape to a squamous shape. Only found in urinary tract

Front 34

What two stratified cells do we never do in lab/lecture?

Back 34

Stratified Cuboidal and Stratified Columnar

Front 35

Properties of Stratified Epithelial Tissues

Back 35

- Contain 2 or more layers of cells

- Regenerate from below (basal layer)

- Older cells push up towards apical side

Front 36

Transitional Epithelium has characteristics of...

Back 36

... stratified cuboidal and stratified squamous

Front 37

Transitional epithelium has ____cells

Back 37

superficial cells (scalloped edge)

Front 38

______- ______ when bladder is relaxed and ________ when full

Back 38

dome shaped when bladder is relaxed and squamous when full

Front 39

How do you structurally classify glandular epithelium (exocrine)

Back 39

Unicellular, Multicellular

Front 40

Unicellular

Back 40

- Single cells

- Goblet cells - mucus carried to outside surface of mucous membrane

Front 41

Multicellular

Back 41

- Composed of many cells that form a distinctive microscopic structure or macroscopic organ (sweat,oil,salivary glands)

Front 42

Exocrine Glands

Back 42

- has ducts

- sweat,oil,salivary glands

Front 43

Methods of Secretion

Back 43

- Merocrine glands

- Holocrine glands

- Apocrine glands

Front 44

Merocrine glands (eccrine glands)

Back 44

- Product secreted out of cells (exocytosis)

- Tear glands, pancreas, gastric glands, salivary glands

- Make it→put into ducts→exits

Front 45

Holocrine glands

Back 45

- Entire cell and its product eventually secreted

- Sebaceous glands in scalp (sebum)

- Ceruminous glands in auditory canal (cerumen)

- Make wax→into duct→whole cell into duct= product cell made and cell itself=thicker/sticky

Front 46

Apocrine glands

Back 46

- Mainly merocrine in secretion

- Bacteria may feed off of secretions, or portions of cell may be secreted

- Mammary and axillary glands (scent glands)

- Bacteria causes smell

Front 47

Apocrine glands aren't activated until...

Back 47

...puberty

- Merocrine→Appocrine

- Shows that you are fertile

- Axillary and Groin region

Front 48

Unicellular Exocrine Gland (The Goblet Cell)

Back 48

- Goblet cells produce mucin

- Mucin + Water → Mucus

- Protects and lubricates many internal body surfaces

Front 49

Pseudostratified Ciliated Columnar Epithelium

Back 49

- Looks like multiple layers but simple

- Found in some of the mucous membranes of the respiratory tract like the lining of the trachea