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Histology Exam III Material > Integument II > Flashcards

Flashcards in Integument II Deck (63)
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1

How thick is the dermis

0.5 to 3 mm thick

2

Dermis corresponds to _______ of a mucous membrane

lamina propria

3

Synonyms for Subcutaneous tissue

-Sub Q
- Superficial fascia
- Hydodermis

4

What is directly related to finger prints

Primary dermal ridge

5

Primary dermal ridge is found everywhere except

forehead, external ear, perineum, and scrotum

6

Primary dermal ridges are formed during

3rd to 4th months of fetal life

7

Primary dermal ridges are subdivided into

two secondary ridges by interpapillary peg

8

What is the interpapillary peg

-It is a downward growth along the crest

- subdivides primary dermal ridge into two secondary dermal ridges

9

Secondary dermal ridges occur in ______ rows, Branched

double

10

Composition of the secondary dermal ridges

Thin collagenous, reticular, and elastic fibers

11

What are dermal papillae

upward projections from each secondary dermal ridge

12

Functions of the integument

-protection from mechanical injury

- Prevents desiccation

- Protects against foreign substances and microorganisms

- Protects against UV radiation

- Thermoregulation

- Regulation of blood pressure (via dermal capillary network)

- Excretion of metabolic waste products

- Synthesis of Provitamin D

13

Integument regulates blood pressure via

dermal capillary network

14

Thick and thin skin refers to the _______ only

epidermis

15

Characteristics of thick skin

-Occurs only on palm and soles and is HAIRLESS
- epidermis varies from 0.4 to 0.6 mm thick
- Displays all five epidermal layers

16

Characteristics of thin skin

- Occurs everywhere except for palms and soles
- epidermis varies form 75 to 150umm thick
- Thinnest skin is on the eyelids
- thickest thin skin is on the back
-thicker on extensor surfaces than flexor surfaces
- epidermal layers less distinct and lacking stratum lucidum

17

Where is the thinnest thin skin

eyelids

18

Where is the thickest thin skin

on Back

19

Epidermal layers of thin skin are _____ and lacking _______

less distinct, stratum lucidum

20

Epidermis is derived from

embryonic ectoderm

21

Layers of epidermis (from deepest to most superficial)

-Stratum basal (germinativum)
-Stratum spinosum (Stratum Malpighi)
-Stratum Granulosum
- Stratum lucidum
- Stratum corneum

22

Langerhans cells are found in what epidermal layer

Stratum spinosum (Stratum Malpighi)

23

The stratum lucidum is absent in

thin skin

24

in thin skin the stratum granulosum is represented by

only a few cells

25

Melanocytes originate in the _____ and are visible form the _____ embryonic week

neural crest, 8th

26

Characteristics of stratum Basale (germinativum)

-Deepest
-Columnar to high cuboidal keratinocytes
- Keratins 5 and 14 (low-molecular weight keratins)
- Single layer of cells
- Held together by desmosomes
- Hemidesmosomes hold layer to basal lamina
- High mitotic activity
- mitotic activity produces stem cells differentiating keratinocytes
- Affected by chemotherapeutic and radiation treatments

27

Characteristics of Stratum Spinosum

-Polyhedra-shaped cells (prickle cells)
- Keratins 1 and 10 (high molecular weight keratins)
- Keratohyalin granules develop
- Membrane-coating granules first appear
-Lamellar bodies
- Contain lipid, carbohydrate, and hydrolytic enzymes
-Tonofibrils
- Form intercellular bridges

28

Characteristics of Stratum Granulosum

-Multilayered
-Keratins 2e and 9
- Flattened nucleated keratinocytes
- Keratohyalin aggregates:
- Fillagrin induces cross-linkage of keratin filaments by disulfide bonds
- no limiting membrane
- Membrane-coating granules (lamellar bodies)
- Acylglucosylceramide---> intercellular spaces
- Tonofilaments

29

General Organization of the Integument

-Epidermis
- Basement membrane
- Dermis
- Subcutaneous tissue
- Epidermal Ridges

30

What keratins are in the stratum basal (Germinativum)

Keratins 5 and 14 (low-molecular weight keratins)