Lecture 7- Integument Flashcards Preview

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Flashcards in Lecture 7- Integument Deck (69):
1

A 44 year old female is told that she has skin cancer. Some type of carcinoma! This would be cancer of what part of the skin?

Epidermis

2

What is the outermost epithelial layer?

Epidermis

3

What is the layer of connective tissue under the epidermis?

Dermis

4

What is the layer of connective tissue under the dermis?

Hypodermis

5

Where are keratinocytes found?

In the dead and alive tissue of the stratified squamous epithelial cells.

6

As basal cells divide, they move toward which surface?

the apical surface to slough off

7

Does the thickness of the epidermal layer change?

no, it is a very orderly process

8

What are melanocytes?

Dendritic processes that make melanin. Found in the basement membrane.

9

What are Langerhans cells

Dendritic processes that are immune cells

10

Where are Tacticle (Merkel) cells found?

In the basement membrane connecting to a sensory nerve ending

11

There is thick skin and think skin. How do they differ?

The epidermis is thicker in thicker in skin

12

What characterizes the stratum basale? (5)

- one cell layer thick
- cuboidal or columnar cells
- contains hemidesmosomes
- mitotic cells
- contains desmosomes

13

What characterizes the stratum spinosum? (5)

- does not contain hemidesmosomes
- contains desmosomes
- has some mitotic cells
- thicker in thick skin than in thin skin
- Active cells

14

How are tonofibrils formed?

Keritanocytes in the stratum spinosum produce keratin that forms the intermediate filaments or tonofibrils in the epidermis.

15

Intermediate filaments are involved in intercellular adhesion. Is this via adherent junctions, desmosomes, or tight junctions?

Desmosomes

16

How would you describe the nuclei in keratinocytes in the stratum spinosum?

Euchromatic nucleus producing a lot of protein

17

Describe the outer cell body of the stratum spinosum.

prickly or spiny

18

What characterizes the stratum granulosum? (4)

- squamous
- Only 3-5 layers of cells
- Cells develop a lipid envelope
- Cytoplasm has basophilic masses

19

How does profilaggrin stain?

intensely blue has a lot of phosphate groups that are very acidic, basophilic and stain blue. Exception to proteins staining pink*

20

Where are the lamellar granules produced and what is their function?

Lipids produced in the cells and are exocytosed to form a layer around the plasma membrane to act as part of the water barrier of skin

21

What is the purpose of filaggrin?

Fillagrin brings keratin and tonofilaments together to condense them.

22

What is keratinization?

The process of binding keratin to filaggrin

23

What characterizes the stratum lucidum? (3)

- see only in thick skin
- cells have lost their nuclei and organelles
- have desmosomes

24

How thick is stratum lucidum?

only a couple cell layers

25

What is the stratum corneum?

Nonnucleated, keratinized cells called squames or cornified cells that have lost their desmosomes and will slough off

26

Having fair skin increases your risk of skin cancer because there is:

Less melanin in keratinocytes

27

How do melanocytes stain?

Stains much clearer around the nucleus than other basal cell layers

28

How do melanocytes orient themselves in the keratinocyte?

In the supranuclear cap to protect DNA from UV radiation

29

Where are Langerhans cells and how do they stain?

Stratum spinosum and stain brown

30

What do langerhans cells do?

They are immune cells that phagocytize antigens. They exit the skin and move to lymph nodes.

31

What can you find in the dermis of the skin? (6)

- blood vessels
- connective tissue
- hair
- sebaceous and sweat glands
- sensory receptors

32

What is the purpose of the epidermal ridges and dermal papilla?

Strength- to reinforce the dermal- epidermal junction. The dermal layer provides nutrients for the epidermis.

33

What are the two layers of the dermis?

- papillary layer (top)
- reticular layer

34

What type of collagen is found in the derms?

Type 1- lots in the reticular layer

35

How does the papillary and reticular layers differ?

-More fine collagen, elastin fibers, and more cells in papillary layer.
- Course collagen, elastin, less cells in reticular

36

a 34 year old female is stung by a bee, she develops hives and itchiness. What is going on in the skin to cause this reaction?

Mast cells degranulate and release histamine

37

What will cause the itching?

Free nerve endings

38

What do the free nerve endings sense?

Itch, light touch, temperature

39

What is the merkel disc?

The end of the process of an axon.

40

What do merkel discs sense?

light touch

41

What does the root hair plexus sense?

movement of hair

42

What type of structures are the merkel discs, free nerve endings and root hair plexuses?

Simple nerve endings without a cover

43

What is a meissner corpuscle?

Unmyelinated nerve ending surrounded by modified schwann cells and capsule that is adjacent to epithelial cells.

44

Where are Meissner corpuscles found?

Concentrated in the finger tips, hands, soles of feet, lips, and tongue. No hair on this skin. Senses light touch.

45

What is a Pacinian corpuscle?

An axon surrounded by layers of modified Schwann cells and outer CT capsule that may be near adipocytes.

46

Where are Pacinian corpuscle's found?

Either deep in the dermis or the hypodermis

47

What type of touch would Pacinian corpuscles sense?

Course touch, pressure and vibrations

48

What is the shaft of hair?

The portion you can see

49

What is the root of hair?

The portion within the skin

50

What is the hair bulb?

The base of the hair follicle

51

That kind of tissue is hair?

epithelial tissue, located in the dermis but comes from epithelial origin.

52

What makes up the invagination of the epidermis for the hair follicle?

The external root sheath surrounded by the Matrix

53

What muscle attaches to hair?

Arrector pilli muscle

54

What is the dermal papilla?

CT with blood vessels. Damage to the dermal papilla that impairs flood supply can prevent hair growth.

55

What makes up the matrix?

Dividing epithelial cells and melanocytes which give hair its color.

56

How does cells move in hair cells?

Cells move up and are keratinzed to form hair root and then shaft

57

Where do the hair and internal root sheath come from?

Matrix cells

58

What does the external root sheath come from?

Invaginated epidermal cells

59

What is the glassy membrane?

Similar to the basement membrane

60

What surrounds the glassy membrane?

The connective tissue sheath

61

What cells are found in sebaceous glands?

sebocytes

62

Why are the sebocytes not stained?

- Cytoplasm is filled with fat droplets
- sebum is a waxy mix of cholesterol and fats that coat the skin and hair

63

Where do you not find sebaceous glands?

- palms of hands
- soles of feet

64

How is sebum secreted into the hair follicle?

Holocrine secretion

65

Where are eccrine sweat glands found?

All over

66

Where are apocrine sweat glands found?

axillary and perineal regions

67

What are the main characteristics of eccrine sweat glands?

- small lumen
- stratified cuboidal epithelium
- duct

68

What are the main characteristics of an apocrine sweat gland?

- large lumen
- cuboidal epithelium with underlying myoepithelial cells
- lumens are fuller and more empty

69

A 14 year old male presents to the emergency department after consuming some jimson weed. His body temperature is elevated and his skin, in general, appears hot and dry. Which is not functioning properly because of the jimsom weed?

Eccrine glands