Lab 1: Skin and Epithelial Tissue

Question 1

describe H&E stain

Answer 1

hematoxylin and eosin

Question 2

describe hematoxylin

Answer 2

blue-purple
basic

Question 3

what structures does hematoxylin dye

Answer 3

dyes acidic structures which are basophilic
- DNA/nucleus, etc

Question 4

describe eosin

Answer 4

pink
acidic

Question 5

what structures does eosin dye

Answer 5

dyes basic structures which are acidophilic
- cytoplasm, collagen, muscle fibers, etc

Question 6

what are structures dyed by eosin called

Answer 6

eosinophilic

Question 7

name the 4 basic tissues

Answer 7

epithelial
connective
muscular
nervous

Question 8

what are the 3 main types of epithelial tissue

Answer 8

simple (simple)
stratified (compound)
pseudostratified

Question 9

name simple epithelial tissue (types and a location)

Answer 9

squamous - endothelium
cuboidal - thyroid
columnar - GI tract

Question 10

name stratified epithelial tissue (types and a location)

Answer 10

squamous - skin
cuboidal - sweat duct
transitional - urinary bladder

Question 11

where is pseudostratified found

Answer 11

trachea

Question 12

describe characteristics of epithelial tissue

Answer 12

rests on a BM (basement membrane)
epithelial tissue is avascular
may be keratinized or non keratinized

Question 13

what does avascular mean

Answer 13

lacks blood vessels

Question 14

where is keratinized epithelial tissue found

Answer 14

epidermis

Question 15

where is non keratinized epithelial tissue found

Answer 15

esophagus

Question 16

name layers of skin

Answer 16

epidermis
dermis
hypodermis

Question 17

where is site of BM

Answer 17

between epidermis and dermis

Question 18

name layers of the epidermis (top to bottom, 4)

Answer 18

stratum corneum
stratum granulosum
stratum spinosum
stratum germinativum

Question 19

describe stratum granulosum (gen/1 fact)

Answer 19

keratohyalin granules

Question 20

name the main objectives of the microscope

Answer 20

scanning x4
low power x10
high dry x40
oil immersion x100 (dont use tho)

Question 21

describe the condenser

Answer 21

condenses light into parallel beams
diaphragm - make sure numbers match objective

Question 22

how to determine final magnification

Answer 22

multiply objective by 10 (since eyepieces are x10)

Question 23

describe objectives

Answer 23

all are parfocal - once image is focused with low power it is almost in focus and only requires fine focusing

Question 24

what type of epithelium is the epidermis

Answer 24

stratified squamous keratinized epithelium

Question 25

what are the dermis and hypodermis made of

Answer 25

connective tissue

Question 26

nuclei, DNA, RNA appear...

Answer 26

basophilic blue

Question 27

cytoplasm and proteins appear...

Answer 27

red

Question 28

describe BM

Answer 28

not visible in skin - but must know general location in between epidermis and dermis

Question 29

what is epidermis lined by

Answer 29

basement membrane

Question 30

name the first layer of cells resting on BM

Answer 30

stratum germinativum (stratum basale)

Question 31

describe stratum germinativum

Answer 31

single layer of columnar shaped cells

Question 32

what do cells in stratum germinativum do

Answer 32

actively divide responsible for regenerating epidermis

Question 33

what are cells joined to the BM by (stratum germinativum)

Answer 33

hemidesmosomes

Question 34

describe stratum spinosum

Answer 34

several layers of polygonal shaped cells

Question 35

what are cells joined together by (stratum spinosum)

Answer 35

desmosomes

Question 36

why is stratum spinosum referred to as spinosum

Answer 36

because tonofibrils gives cells a spiny appearance

Question 37

what are tonofibrils

Answer 37

visible fibers that insert into the cellular junctions

Question 38

describe stratum granulosum

Answer 38

2-5 layers of cells flattened and contain basophilic (blue) granules called keratohyalin granules

Question 39

what is the surface layer called

Answer 39

stratum corneum

Question 40

describe stratum corneum

Answer 40

non nucleated cells & have cytoplasm filled with keratin

Question 41

what happens in stratum corneum

Answer 41

desmosomes begin to breakdown cells at surface are shed (de-squamation)