L8: Epithelial tissue

Question 1

Epithelium plays an important role in

Answer 1

Diffusion
Absorption
Secretion

Question 2

Tissue is:

Answer 2

• A diverse group of cells
• With an ordered structure
• Working together for a common function

Question 3

4 types of tissue:

Answer 3

• Epithelial
• Connective
• Muscle
• Nervous

Question 4

The basic characteristic of epithelial tissue:

Answer 4

• Covers body surface, lines body cavities
• form glands (skin, airways, digestive lining, and urinary tract lining)
• Closely packed cells
• little extracellular materials
• Basement membrane
• Avascular
• Highly regenerative (using stem cells) (high mitotic activity)

Question 5

cells in epithelial tissue are joined by….

Answer 5

by Specialized cell-to-cell junctions

Question 6

describe the Basement membrane:

Answer 6

• It’s a non-cellular membrane

- Compromised of polysaccharide-rich membrane

Question 7

The function of basement membrane:

Answer 7

• Separates epithelium from underlying connective tissue

- Acts as a sieve to prevent materials from entering the body

Question 8

The key characteristic of epithelial tissue?

Answer 8

Avascular

Question 9

why is the epithelial cell highly regenerative

Answer 9

Cells completely lack bloody supply (that’s why they’re highly regenerative)

Question 10

which is side is the Free surface

Answer 10

• Is the apical side

- Bound to the basolateral side

Question 11

The function of epithelial tissue:

Answer 11

• Secretion
• Selective absorption
• Protection
• Transcellular transport
• Detection of sensation

Question 12

Examples of secretion:

Answer 12

• Digestive tract

- Involved in high secretion activity

Question 13

Selective absorption:

Answer 13

• First contact with the material

- And allows them to be absorbed

Question 14

selective absorption is associated with a structure known as

Answer 14

microvilli (inc surface area)

Question 15

the function of Transcellular transport:

Answer 15

• aid the movement of substances from cell-to-cell through a certain distance
• Ex: mucus

Question 16

What structure does transcellular transport:

Answer 16

cilia

Question 17

Detection of sensation:

Answer 17

• 1st layer with the outer environment

- To detect sensation along with nerve cells

Question 18

types/identifications of epithelial tissues:

Answer 18

• 1st through cell shape

- Then layers

Question 19

Cell shape types:

Answer 19

• Squamous (flat)
• Cuboidal (rectangle)
• Columnar (very elongated)

Question 20

Surface specialization:

Answer 20

• Keratin
• Microvilli
• Cilia

Question 21

Keratin:

Answer 21

• Its a protein for hair

- Composes a thick layer of dead cells as protection around the epidermis

Question 22

Microvilli:

Answer 22

• Inc surface area
• Absorption
• Found in intestine

Question 23

Cilia:

Answer 23

Involved in motility of substances in the human body

Question 24

type of layers identification of epithelium

Answer 24

• Simple
• Stratified (multilayer)
• Pseudostratified
• Transitional

Question 25

Pseudostratified:

Answer 25

Disorganized layering of epithelial tissue that is not simple or stratified

Question 26

Transitional:

Answer 26

A huge number of disorganized, disproportionate number of epithelia

Question 27

Transitional is typically found in:

Answer 27

- Urinary bladder | - Why: bc this structure allows the extension & distention of the organ itself

Question 28

Simple squamous make up the:

Answer 28

- Alveoli (air sacs of the lung) - The lining of all blood vessels & capillaries (endothelium) - Various membranes within the body (peritoneum = area where there's a lot of exchange) - Glomerulus of kidney

Question 29

Does it make sense that simple squamous make up The lining of all blood vessels & capillaries (endothelium)

Answer 29

- Yes - Why: bcs the flatter the surface = the simpler & lesser the layers - = the more likely it is going to play an important role in facilitating gas exchange

Question 30

Simple cuboidal makes up the:

Answer 30

- Collecting tubules of the - kidney - Liver - Pancreas - Thyroid - & other glands of the body (synthesis of hormones)

Question 31

Simple columnar epithelium ciliated makes up:

Answer 31

The lining of the ovary ducts (fallopian tubes)

Question 32

Simple columnar microvilli epithelium with goblet cells makes up:

Answer 32

- The lining of the intestine | - Secretes mucus

Question 33

Stratified squamous epithelium:

Answer 33

- Located in areas of body subjected to abrasion

Question 34

what are the 2 types of Stratified squamous epithelium

Answer 34

Keratinizing stratified squamous non-Keratinizing stratified squamous:

Question 35

where can you find Keratinizing stratified squamous:

Answer 35

Skin

Question 36

where can you find non-Keratinizing stratified squamous:

Answer 36

- Tongue - Oral mucosa - Esophagus - Vagina

Question 37

Stratified cuboidal epithelium found in:

Answer 37

- Sweat glands - Salivary glands - Ovarian follicles - Seminiferous tubules

Question 38

Stratified cuboidal epithelium secretes:

Answer 38

- Sweat - Ovarian hormones - Sperm

Question 39

Stratified columnar epithelium are:

Answer 39

- Rare | - Located in the largest ducts of salivary glands (parotid, submandibular)

Question 40

The basal layer in stratified columnar are:

Answer 40

- Cuboidal cells - & the layer nearest the apical surface includes columnar cells - The large droplets are mucus in goblet cells

Question 41

Epithelia are classified according to

Answer 41

- Cells nearest the lumen | - In stratified columnar case its = columnar

Question 42

Pseudostratified columnar ciliated epithelium with goblet cells:

Answer 42

- Makes up = lining of the respiratory tract | - Secretes mucus moves mucus, trap foreign particles

Question 43

Transitional epithelium: (makes up what)

Answer 43

- Makes up: the lining of the urinary bladder & the ureter | - Stratified tissue becomes stretched as the urinary bladder becomes filled with urine (distention)