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Flashcards in Epithelia and skin Deck (18)
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1

What are the diameters of FOV for each objective lense?

x 4 = 4.5mm

x 10 = 1.8mm

x 40 = 0.45mm

2

What are the different arrangements of epithelium?

1. Simple epithelium

2. Stratified epithelium

3

What are the different types of simple epithelium?

1. Squamous (diffusion surfaces, e.g. alveoli, endothelium)

2. Cuboidal (absorption/secretion, e.g. small exocrine ducts, nephron)

3. Columnar (absorption/secretion, e.g. intestines, large exocrine ducts)

4. Pseudostratified (airway, e.g. trachea)

4

What are the characteristics of transitional epithelium?

- Surface (umbrella) cells are large, dome-shaped and often overlap 2 or more cells beneath.

- Basal/intermediate cells are polygonal in shape and change size depending on distension.

5

Where is transitional epithelium found?

- Bladder

- Ureters

- Parts of urethra

6

How can cilia be distinguished from microvilli in EM?

Cilia contain microtubules while villi don't

7

What are the structures present in junctional complex?

1. Tight junction (zonula occludens)

2. Intermediate junction (zonula adherens)

3. Desmosome (macula adherens)

4. Gap junction

8

What are the layers of skin?

1. Epidermis

2. Dermis

3. Hypodermis

9

What are the layers of the epidermis?

1. Stratum corneum: Dead, flattened, innulceated cells full of keratin.

(2. Stratum lucidum: Thick skin only)

3. Stratum granulosum: Cells containing dense cytoplasmic granules contributing to keratin formation.

4. Stratum spinosum: Cells containing cytoplasmic spines.

5. Stratum germinativum (stratum basale): Cuboidal cells anchored to the basement membrane that carry out active cell division.

10

What type of epithelium is skin?

Stratified keratinised squamous epithelium

11

What do the spines in the stratum spinosum represent?

Punctate desmosomes binding each adjacent cell

12

What are the layers of the hair follicle?

1. External root sheath: Downward epidermal extension

2. Cuticle

3. Cortex

4. Medulla

5. Inner root sheath

13

What structures are associated with the hair follicles?

- Sebaceous glands

- Arrector pili muscles

14

What are the types of sweat glands?

1. Eccrine

2. Apocrine

15

What is the function and location of Pacinian corpuscules?

Function: Detect deep pressure and vibration

Location: Hypodermis

16

What type of epithelium is found in sweat glands?

- Secretory portion: Simple cuboidal epithelium

- Duct: Stratified (2 layers) cuboidal epithelium

17

What are the places in the body that don't have sweat glands?

- Lips

- External genitalia

18

What is the function of the terminal web?

To allow for limited movement of cell apex and microvilli