Epithelium

Question 1

Four types of tissue

Answer 1

Nervous
Epithelial
Muscle
Connective

Question 2

Steps for preparing tissue for light microscopy

Answer 2

1-Fixation- preserve tissue
2-Dehydration in graded concentrated ethyl alcohol- replace tissue water
3-Clearing in benzene, xylene or toluene- impregnate tissues with solvent
4-Embedding- paraffin @ 60c or plastic resin @ RT
-tissue more resistant to sectioning

Question 3

3 basic steps for prep

Answer 3

Fixation
Sectioning
Staining

Question 4

Stains

Answer 4

Eosin- stains +

Hematoxylin- stains -

Question 5

Eosin

Answer 5

Stains cytoplasm, cytoplasmic filaments, collagen fibers, and basement membrane

Question 6

Hematoxylin

Answer 6

Stains heterochromatin, nucleolus, the Rough ER, sulfated GAGs

Question 7

H&E

Answer 7

used to distinguish nucleus from cytoplasm

Question 8

Simple squamous distribution

Answer 8

• Lining of vessels
• Serous lining of cavities
• Pericardium
• Pleura
• Peritoneum

Question 9

Simple squamous function

Answer 9

Facilitates movement
secretion
active transport- pinocytosis

Question 10

Simple cuboidal distribution

Answer 10

Covering the ovary and thyroid

Question 11

Simple cuboidal function

Answer 11

Covering and secretion

Question 12

Simple columnar distribution

Answer 12

Lining of intestine and gallbladder

Question 13

Simple columnar function

Answer 13

Protection, lubrication, absorption, secretion

Question 14

Pseudostratified distribution

Answer 14

Lining of trachea, bronchi, nasal cavity

Question 15

Pseudostratified function

Answer 15

Protection, secretion, cilia-mediated transport of particles trapped in mucus

Question 16

Stratified squamous keratinized distribution

Answer 16

Epidermis

Question 17

Stratified squamous keratinized function

Answer 17

Protection and prevent water loss

Question 18

Stratified squamous nonkeratinized distribution

Answer 18

Mouth, esophagus, larynx, vagina, anal canal

Question 19

Stratified squamous nonkeratinized function

Answer 19

Protection, secretion, prevent water loss

Question 20

Stratified cuboidal distribution

Answer 20

Sweat glands, developing ovarian follicles

Question 21

Stratified cuboidal function

Answer 21

Protection, secretion

Question 22

Pseudostratified Transitional distribution

Answer 22

Bladder, ureters, renal calyces

Question 23

Pseudostratified transitional function

Answer 23

Protection, distensibility

Question 24

Stratified Columnar distribution

Answer 24

Conjunctiva

Question 25

Stratified Columnar function

Answer 25

Protection

Question 26

Epithelial cells in the digestive/respiratory/urinary system rest on

Answer 26

layer of connective tissue calls lamina propria

Question 27

Basal lamina and basement membrane

Answer 27

Separation of epithelium from connective tissue

Question 28

Basal lamina made up of

Answer 28

Type IV collagen Laminin Entactin Proteoglycans Can only be seen under EM

Question 29

Basement membrane

Answer 29

Reticular fibers- type III collagen Can be seen under light microscope

Question 30

Hemidesmosomes

Answer 30

Help bind epithelial cells to the basal lamina

Question 31

Striated border

Answer 31

Microvilli and glycocalyx found in small intestine

Question 32

Brush border

Answer 32

Longer complex of microvilli found on proximal renal tubule

Question 33

Sterocilia

Answer 33

Long | Nonmotile extensions of the apical suface

Question 34

Cilia

Answer 34

Found on the apical surface of respiratory system | 9+2 arrangement of microtubules

Question 35

Myoepithelial cells

Answer 35

Found in secretory units of - mammary - sweat - salivary glands

Question 36

Endothelium

Answer 36

Simple squamous epithelium | -ling blood vessels and lymphatic vessels

Question 37

Mesothelium

Answer 37

Simple squamous epithelium lining body cavities | -peritoneum

Question 38

Epitheioid

Answer 38

Tissues that contain cells that are closely associated | -resembling an epithelium

Question 39

Stem cells of the skin

Answer 39

Basal layer of the epidermis

Question 40

Atrophy

Answer 40

death

Question 41

Hypertrophy

Answer 41

increase in size

Question 42

hyperplasia

Answer 42

increase in number

Question 43

Dysplasia

Answer 43

change in orginization

Question 44

metaplasia

Answer 44

transformation into another cell type | -respiratory cells can be transformed into stratified squamous epithelium

Question 45

Thin and thick skin are distinguished by

Answer 45

the thickness of the epidermal layer

Question 46

Thick skin

Answer 46

Found on the palms and soles | -lacks epidermal appendages-- such as hair follicles and sebaceous glands

Question 47

Stratum basale

Answer 47

Single layer of stem cells | -closest layer to connective tissue

Question 48

Stratum spinosum

Answer 48

Mitotically active prickle cell layer

Question 49

Stratum granulosum

Answer 49

Non-proliferating cells with stained granules

Question 50

Stratum lucidum

Answer 50

clear layer seen only in thick skin!!

Question 51

Stratum corneum

Answer 51

Keratinized cell ghosts | -top layer

Question 52

Keratinocytes

Answer 52

Contain a lipid mix that is discharged to form the epidermal water layer

Question 53

Melanocytes

Answer 53

Derived from neural crest cells in stratum basale # is the same in all races- skin color due to # and distribution of melanin granules in keratinocytes

Question 54

Langerhans cells

Answer 54

Antigen-presenting cells -derived from bone marrow Component of SALT- skin associated lymphoid tissue

Question 55

Merkel cells

Answer 55

epithelial tactile cells - Mainly found in stratum basal - More numerous in thick skin - sensitive mechanoreceptor in areas such as fingertips