Lecture 7- Integument Flashcards Preview

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Flashcards in Lecture 7- Integument Deck (69)
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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.