LECTURE 1 epithelial tissue Flashcards Preview

anatomy lecture exam 1 > LECTURE 1 epithelial tissue > Flashcards

Flashcards in LECTURE 1 epithelial tissue Deck (34):
1

functions of epithelial tissue (4)

protection, secretion (release molecules to surface), absorption (taking molecules into tissue), ion transport

2

characteristics of epithelium (7)

cellularity, specialized contacts, polarity, supported by connective tissue, avascular, innervated, highly regenerative

3

classification of epithelium: layers of cells (3)

simple, stratified, pseudostratified

4

classification of epithelium: shape of cells (3)

squamous, cuboidal, columnar

5

endothelium

(special epithelium) simple squamous epithelium that lines vessels (lymphatic and blood vessels, chambers of heart)

6

mesothelium

(special epithelium) simple squamous epithelium that forms the lining of body cavities (thoracic, abdominal, pleura, pericardium, peritoneum)

7

microvilli

(feature of apical surface) finger-like extensions of the plasma membrane of apical epithelial cell that increases surface area for absorption (in small intestine)

8

cilia

(feature of apical surface) whip-like, motile extension of plasma membrane that moves mucus (etc.) over epithelial surface one way (in respiratory tubes)

9

features of apical surface (2)

microvilli, cilia

10

cellularity (characteristic of epithelium)

many cells packed close together, small amount of extracellualr material around them

11

specialized contacts (characteristic of epithelium)

cells are joined by varying types of cell junctions (can be proteins, can change permiability)

12

polarity (characteristic of epithelium)

apical vs. basal surfaces differ (two distinct ends/surfaces), apical is free and unattached and next to lumen, basal is attatched to connective tissue - supported by CT because that's where it gets nutrients from blood (since epithelium is avascular)

13

highly regenerative (characteristic of epithelium)

mitosis frequently and rapidly, epithelial cell lifespan usually two days

14

classification of epithelium

based on number of layers and cell shape

15

layers of epithelium

simple (one layer), stratified (multiple layers, characterized by shape of apical layer), pseudostratified (looks like multiple layers but only one, cells of different height that all touch basal surface)

16

shapes of epithelial cells

squamous (wider than tall, distance between apical and basal), cuboidal (even height to width, not perfect cube), columnar (taller than wide)

17

structure of epithelium

forms sheets of cells that cover a surface or line a cavity

18

simple squamous found in

lungs, blood vessels, ventral body cavity

19

simple cuboidal found in

kidney tubules, glands

20

simple columnar found in

stomach, intestines

21

pseudostratified columnar found in

respiratory passages (ciliated version)

22

stratified squamous found in

epidermis, mouth, vagina, esophagus

23

features of lateral surface

contour of cells (looks wavy as it fits together), cell junctions

24

desmosome

(lateral cell junction) proteins hold cells together to maintain integrity

25

tight junction

(lateral cell junction) plasma membrane of adjacent cells fuse, nothing passes

26

gap junction

(lateral cell junction) proteins allow small molecules to pass through

27

features of basal surface

basement membrane

28

basement membrane

(feature of basal surface) sheet between epithelium and connective tissue layers, attaches epithelium to connective tissue

29

basal lamina

(basement membrane) thin, non-cellular, supportive sheet made of proteins, superficial layer of basement membrane, acts as a selective filter, assists epithelial cell regeneration by moving new cells

30

reticular fiber layer

(basement membrane) deeper, supportive layer

31

glands

epithelial cells that make and secrete a product, products are water-based and usually contain proteins

32

gland classification

unicellular vs. multicellular, exocrine vs. endocrine

33

exocrine glands

secrete substance onto body surface or into body cavity, produce a variety of types of products, activity is local, have ducts, unicellular or multicellular, ex: goblet cells, salivary, mammary, pancreas, liver

34

endocrine glands

secrete product into blood stream, either stored in secretory cells or in follicle surrounded by secretory cells, always produce hormones, no ducts, unicellular or multicellular, activity is widespread, ex: pancreas, adrenal, pituitary, thyroid