Chap 1 Part 2

Question 1

What kind of epithelium is two or more cell layers thick?

Answer 1

stratified epithelium

Question 2

What kind of function is shared by all stratified epithelium>?

Answer 2

protection

Question 3

Stratified Squamous epithelium have multiple layers of cells that tend to flatten out from basal layer to superficial layer. Where can this type of epithelium be found?

Answer 3

esophagus, oral cavity, tongue and vagina

Question 4

Although stratified squamous epithelium protects against abrasion, is protection is limited. Why? What are its limitations?

Answer 4

limited thickness; no protection from drying

Question 5

What is the function of Keratinized Stratified Squamous epithelium?

Answer 5

Protection in a dry environment

Question 6

What are the layers in epithelium of skin?

Answer 6

stratum basale, stratum spinosum, stratum granulosum, stratum lucidum, stratum corneum (Boys Seldom Get Lucky Consistently)

Question 7

Which layer of the keratized stratified squamous is composed of 1-2 layers of keratinocytes which are mitotic and closest to the dermis?

Answer 7

stratum basale (germinativum)

Question 8

Which layer of the keratinized stratified squamous is composed of multiple layers of “spiny shaped” keratinocytes? Thickness of this layer can vary.

Answer 8

Stratum Spinosum

Question 9

Which layer of the keratinized stratified squamous can be described as the uppermost 2-5 layers of flattened living keratinocytes where exocytosis of lipid-filled lamellar granules will occur?

Answer 9

stratum granulosum

Question 10

Which layer of the keratinized stratified squamous is not easy to see, present only in thick skin, and is a thin layer of recently dead or dying keratinocytes?

Answer 10

stratum lucidum (nucleus and organelles are not present)

Question 11

Which layer of the keratinized stratified squamous is composed of dead cells, karatin, and lipids? It also has 3 distinct functions.

Answer 11

stratum corneum

Question 12

What are the 3 functions of the stratum corneum?

Answer 12

prevents water loss, barrier to microbes, and protects against abrasion

Question 13

T/F: thickness varies in the stratum corneum and stratum spinosum.

Answer 13

True

Question 14

What is the the Malpighian layer?

Answer 14

stratum basale and stratum spinosum; a way of grouping layers together where cell division can occur

Question 15

How do epidermal pegs (rete ridges) and dermal papillae contribute to the strength of epithelium?

Answer 15

increase surface area for attachment of the epithelium to the CT below

Question 16

How long do epithelial cells live?

Answer 16

about 28 days

Question 17

Melanocytes do what and are found where?

Answer 17

protect against UV radiation; stratum basale

Question 18

What occurs with increased UV light exposure (with regard to melanocytes)?

Answer 18

skin color greatly influenced; melanocytes increase, increasing melanin

Question 19

T/F: melanocytes are about equal in all humans.

Answer 19

True

Question 20

Which type of cell recognizes external foreign antigens, is an epidermal dendritic cell, a resident APC, and is found in the stratum spinosum?

Answer 20

Langerhans Cells

Question 21

Which type of cell provides touch receptors, is associated with free nerve endings (very numerous in areas of high sensitivity) and is found in the stratum basale layer?

Answer 21

Merkel cells (fingertips and hair follicles)

Question 22

T/F: Melanocyte numbers decrease with repeated UV exposure.

Answer 22

False; this is true of Langerhans cells, melanocyte numbers increase

Question 23

What are the 5 types of stratified epithelium?

Answer 23

stratified squamous, keratinized stratified squamous, stratified cuboidal, stratified columnar, and transitional

Question 24

Which types of stratified epithelium function in protection?

Answer 24

all of them

Question 25

Where can you find stratified cuboidal? how many layers?

Answer 25

larger in ducts in sweat glands and salivary glands; 2 layers (basal layer is flattened and superficial is cuboid

Question 26

Wher can stratified columnar be found?

Answer 26

large ducts in pancreas, parts of male urethra and conjunctiva of the eye

Question 27

T/F: stratified columnar epithelium is very rare, and consists of two layers. The basal layer is flattened and the superficial is columnar in shape.

Answer 27

True

Question 28

Other than protection, what function does stratified columnar perform?

Answer 28

provides a transition between epithelial types

Question 29

What/where is transitional epithelium?

Answer 29

Urinary epithelium or urothelium; found in most of urinary tract

Question 30

Other than protection, what function is transitional epithelium specialized to do?

Answer 30

stretch

Question 31

What part of transitional epithelium is thin and fenestrated? which part is large and rounded? And which part is well developed?

Answer 31

basement membrane, superficial cells, and zonula occludens/tight junctions (respectively)

Question 32

Why is it important that transitional epithelium has a well-developed zonula occludens?

Answer 32

prevents wastes (urine) from seeping out; needed because of fenestrated basement membrane

Question 33

T/F: when transitional epithelium is stretched, distance of diffusion is increased.

Answer 33

False; the distance of diffusion is decreased therefore more oxygen can actually get into the cells

Question 34

Where do cells accumulate during psoriasis vulgaris (patchy skin lesions)?

Answer 34

in stratum corneum

Question 35

T/F: Freckles are an increase in melanin and melanocyte numbers.

Answer 35

False; they are an increase in melanin without an increase in melanocyte numbers

Question 36

What are patches which lack melanocytes called?

Answer 36

vitiligo

Question 37

What is the term for discolorization due to proliferation of melanocytes?

Answer 37

moles

Question 38

What is occuring when melanocytes become mitotically active and invade dermis? This is very invasive and metastic requiring surgery/chemotherapy.

Answer 38

malignant melanoma

Question 39

What condition occurs when melanocytes fail to produce melanin?

Answer 39

albinism

Question 40

What enzyme is missing from melanocytes in the most common form of albinism?

Answer 40

tyrosinase (a catalyst in the conversion of tyrosine to melanin)