007 Cell Differentiation- Epithelium

Question 1

4 basic types of tissue

Answer 1

1. epithelia
2. connective tissue
3. muscle
4. nervous tissue

Question 2

mesothelium

Answer 2

epithelium that lines serous body cavities (like inside thorax or the abdomen. aka the serosa that produces serous fluid so that it can rub against each other)

Question 3

endothelium

Answer 3

epithelium that lines blood and lymph vessels

Question 4

epithelium derived from

Answer 4

all three germ layers

Question 5

metaplasia

Answer 5

epithelial cells can change from one type to another due to chronic changes in environmental conditions

Question 6

features of epithelia

Answer 6

little ECM, closely packed
avascular
innervated

Question 7

apical=

basal=

Answer 7

top part
bottom part (basement membrane)

Question 8

four types of apical specializations

Answer 8

1. cilia
2. microvilli
3. stereocilia
4. flagella

Question 9

axoneme

Answer 9

part of the cilia that has a 9+2 arrangement

Question 10

basal body of the cilia attached to the cytoplasm by

Answer 10

striated rootlets

Question 11

components of the cilium

Answer 11

dyne in arm connecting the doublets
doublets made of tubulin
nexin linking protein

Question 12

Primary ciliary dyskinesia/ immotile ciliary syndrome/kartagener syndrome

Answer 12

genetic defect results in uncoordinated or absent cilia
during embryogenesis, cell layers are not moved correctly and the organs are abnormally positioned (situs inversus)
recurrent/severe chest infections due to lack of mucus removal
infertility

Question 13

microvilli

Answer 13

core of cross linked actin microfilaments
not motile
apical side- glycocalyx

Question 14

stereocilia

Answer 14

very long nonmotile microvilli
actin core of microfilaments
absorption and secretion
epididymis and inner ear
branched

Question 15

flagellum

Answer 15

similar to cilia

only form the tail of the spermatozoan

Question 16

tight junction (zonula occludens)

Answer 16

lies near cell apex

form belt like fluid tight seals for isolation

Question 17

paracellular pathway

Answer 17

between adjacent epithelial cells

Question 18

transcellular pathway

Answer 18

through the cell

Question 19

zonula adherens (adhering junctions)

Answer 19

beneath tight junction
cadherins and afadin-nectin complex
terminal web actin microfilaments insert to provide additional stability (connect to a plaque)

Question 20

macula adherens (desmosomes)

Answer 20

link intermediate filaments of the cell cytoskeleton

cadherins span space between the plaques

Question 21

gap junctions

Answer 21

exhibit regulation by being open or closed

imp in cellular communication and embryonic development

Question 22

basement membrane =

Answer 22

basal lamina + reticular lamina(connective tissue)

Question 23

basal lamina =

Answer 23

lamina lucida(farthest in) + lamina densa

Question 24

basement membrane is visible in

Answer 24

light microscopy

Question 25

lamina lucida

Answer 25

extracellular glycoproteins (enactin, integrins and laminin)

Question 26

lamina densa

Answer 26

meshwork of collagen IV fibrils

Question 27

reticular lamina (lamina reticularis)

Answer 27

produced by fibroblasts

composed of collagen I and III

Question 28

hemidemosomes

Answer 28

anchored by keratin intermediate filaments intracellularly

anchored by integrin filaments extracellularly (integrins bind to laminin and collagen IV in basal lamina)

Question 29

two classifications of glands

Answer 29

endocrine- no ducts and secretions delivered to vascular system
exocrine- have ducts and reach the epithelium

Question 30

types of simple exocrine glands

Answer 30

1. simple tubular
2. simple coiled tubular
3. simple tubular branched
4. simple acinar or alveolar

Question 31

types of branched exocrine glands

Answer 31

1. branched tubular
2. branched alveolar/alveolar
3. branched tubuloacinar

Question 32

exocrine- merocrine secretion

Answer 32

the secretory vesicle approaches the apical domain and the vesicular membrane fuses with the plasma membrane to release its contents into the extracellular space

Question 33

exocrine- apocrine secretion

Answer 33

some of the atypical cytoplasm is pinched off with the contained secretions

Question 34

exocrine- holocrine secretion

Answer 34

the cell produces and accumulates a secretory product in the cytoplasm,, such as sebum and then disintegrates to release the secretory material