Csf - Epithelial Cells

Front 1

Functions of epithelia?

Back 1

1. protect
2. selective barrier
3. transport (absorb, secrete, concentrate and store)
4. synthesis (mucus, hormones)

Front 2

Why are epithelial cells polarized?

What makes them polar?

Back 2

Polarizing them makes them efficient for transport.

THE BASEMENT MEMBRANE establishes polarity

Front 3

Do epithelial cells contain vasculature?

Do all epithelial cells have a basement membrane?

Back 3

NO. All epithelia are avascular.

yes - all epithelia have a basement membrane.

Front 4

Where do you make the ID on stratified epithelia?

Back 4

at the top-most surface near the lumen. This tells you if you have squamous, cuboidal or columnar.

***always look at the most simple area on the slide to make the ID

Front 5

Stereocilia are only found in two tissues - which?

Goblet cells are only found where?

Back 5

Stereocilia -ears and testis

Goblet cells are only found on simple epithelia.

Front 6

What is metaplasia?

ex?

Back 6

Change in cells from chronic stress -

smoker's respiratory epithelia

Front 7

What guides repair of epithelia?

Back 7

Basement membrane guides repair of epithelia

Front 8

What is the basement membrane made out of?

Back 8

Basement membrane is made out of PROTEINS AND SUGARS! (not lipids)

Front 9

What are two types of specialized simple squamous epithelia?

Where are they found?

Back 9

Endothelium - simple squamous, found lining heart chambers and blood vessels.

Mesothelium - simple squamous, found in pleural and peritoneal spaces.

Front 10

Is the external lamina unique to epithelia?

Are the cells polarized in the external lamina?

What is the external lamina?

Back 10

Not unique to epithelia.

Cells are NOT polarized.

External lamina is when 2 different kinds of tissues contact each other.
ex) interfaces bt muscle fibers and adipose.

Front 11

Describe the process of epithelial repair.

Back 11

1. cells lose polarity and cells collapse.
2. cells repolarize along horizontal axis
3. mitosis signals sent
4. cells migrate across the membrane
5. when cells meet - polarity reestablished.

Front 12

What is the function of lateral interdigitations between cells?

What kinds of cells are these common in?

Back 12

this increases surface area FOR ION TRANSPORT

Lateral interdigitations are common in cells that absorb fluid from the lumen.

Front 13

What drives passive transport?

What kinds of transporters are always passive?

Back 13

Passive transport is driven by concentration or electrochemical gradient.

CHANNELS are always passive

Front 14

What is active transport?

What is an example of this?

Back 14

needs ATP usually.

it's when particles are transported AGAINST their concentration or electrochemical gradient.

ex) carrier proteins (antiport/symport)

Front 15

What makes up a junctional complex?

Back 15

Tight junctions - adhesion belts - desomsomes (from top to bottom).

Front 16

What are the parts of the basement membrane?

What mag. can you see these?

Back 16

from inside to outside:

lamina rara
lamina densa (type IV collagen)
lamina reticularis (type III collagen)

can only be seen in EM

Front 17

Which parts of the basement membrane are secreted by the epithelial cell?

Which is secreted by the fibroblasts?

Back 17

lamina rara and lamina densa = secreted by epithelia

lamina reticularis = secreted by the fibroblasts.

Front 18

What cytoskeletal elements anchor the adhesion belt?

What holds adhesion belts together laterally?

Back 18

Actin filaments connect adhesion belts to cytoplasm and terminal web.

Cadherins

Front 19

What links desmosomes into the cytoplam?

Where are hemidesmosomes vs desmosomes found?

Back 19

keratin filaments link desmosomes together

Desmosomes are found on lateral surfaces.

Hemidesomsomes are found on the basal surface.

Front 20

What makes up gap junctions?

Back 20

6 IMP structure called a connexon

Front 21

What apical modification do all epithelia have?

What cytoskeletal structure makes these?

Back 21

microvilli made of actin.

Front 22

What are cilia made of? What is their function?

What special features do cilia have?

Back 22

cilia are made of microtubules.

function is movement

have basal bodies near the centriole.

Front 23

What is the function of basal infolding?

Why are a lot of mitochondria found here?

Back 23

increase surface area FOR ION TRANSPORT (kind of like lateral interdigitations but at the BASAL side)

Mitochondria hang out near basal infoldings because ion transport is ACTIVE and requires ATP.

Front 24

What uses cadherins?

Back 24

Desmosomes use cadherins..

HEMIDESMOSOMES DO NOT. They use INTEGRIN PROTEINS.

Front 25

what is an example of a unicellular exocrine gland?

Back 25

goblet cell

Front 26

How can you tell serous from mucous acinus?

Back 26

mucus acinus is clear looking with the nuclei pushed flat against basal side of circle.

Front 27

What kind of exocrine glands release product by exocytosis - both constitutive and regulated?

Back 27

merocrine exocrine glands

Front 28

What kind of exocrine glands pinch off the entire apex when they secrete?

Back 28

Apocrine. A for Apex pinches off.

Front 29

Which kind of exocrine cell is the whole cell secreted?

What is the only example of these.

Back 29

Holocrine. Sounds like "whole".

Sebaceous glands are the only of this kind.