LECTURE 1 epithelial tissue

Question 1

functions of epithelial tissue (4)

Answer 1

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

Question 2

characteristics of epithelium (7)

Answer 2

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

Question 3

classification of epithelium: layers of cells (3)

Answer 3

simple, stratified, pseudostratified

Question 4

classification of epithelium: shape of cells (3)

Answer 4

squamous, cuboidal, columnar

Question 5

endothelium

Answer 5

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

Question 6

mesothelium

Answer 6

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

Question 7

microvilli

Answer 7

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

Question 8

cilia

Answer 8

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

Question 9

features of apical surface (2)

Answer 9

microvilli, cilia

Question 10

cellularity (characteristic of epithelium)

Answer 10

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

Question 11

specialized contacts (characteristic of epithelium)

Answer 11

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

Question 12

polarity (characteristic of epithelium)

Answer 12

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)

Question 13

highly regenerative (characteristic of epithelium)

Answer 13

mitosis frequently and rapidly, epithelial cell lifespan usually two days

Question 14

classification of epithelium

Answer 14

based on number of layers and cell shape

Question 15

layers of epithelium

Answer 15

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)

Question 16

shapes of epithelial cells

Answer 16

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

Question 17

structure of epithelium

Answer 17

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

Question 18

simple squamous found in

Answer 18

lungs, blood vessels, ventral body cavity

Question 19

simple cuboidal found in

Answer 19

kidney tubules, glands

Question 20

simple columnar found in

Answer 20

stomach, intestines

Question 21

pseudostratified columnar found in

Answer 21

respiratory passages (ciliated version)

Question 22

stratified squamous found in

Answer 22

epidermis, mouth, vagina, esophagus

Question 23

features of lateral surface

Answer 23

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

Question 24

desmosome

Answer 24

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

Question 25

tight junction

Answer 25

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

Question 26

gap junction

Answer 26

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

Question 27

features of basal surface

Answer 27

basement membrane

Question 28

basement membrane

Answer 28

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

Question 29

basal lamina

Answer 29

(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

Question 30

reticular fiber layer

Answer 30

(basement membrane) deeper, supportive layer

Question 31

glands

Answer 31

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

Question 32

gland classification

Answer 32

unicellular vs. multicellular, exocrine vs. endocrine

Question 33

exocrine glands

Answer 33

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

Question 34

endocrine glands

Answer 34

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