Extracellular Structures,
Cell Adhesion & Cell
Junctions
Introduction
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What do we mean when we use the
term extracellular structures?
From where do extracellular
structures come?
Of what do extracellular structures
consist?
Extracellular Matrix – Animal Cells
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What are the three types of
macromolecules found in the ECM of
animal cells?
What leads to the variety of the
ECM?
Extracellular Matrix – Animal Cells
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Besides providing stability to the
physical structure of tissues, why
else is the ECM important to cell
function?
The ECM is usually associated with
connective tissue. What are some
examples of connective tissue?
Extracellular Matrix – Animal Cells
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What is the most abundant component of
the ECM?
What do we know about the makeup of
collagen?
Extracellular Matrix – Animal Cells
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How is the collagen fiber assembled?
Extracellular Matrix – Animal Cells
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Different α chains exist (coded by different
genes)
Form different types of collagen
Extracellular Matrix – Animal Cells
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What do collagens have in common
with skeletal muscle?
How are elastins different from
collagens?
What kinds of tissues contain
elastins?
Extracellular Matrix – Animal Cells
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Structurally how do
elastins compare
with collagen?
Extracellular Matrix – Animal Cells
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What are
proteoglycans?
What are
glycosaminoglycans?
Extracellular Matrix – Animal Cells
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How are
proteoglycans
related to the
structure of
cartilage?
Extracellular Matrix – Animal Cells
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What distinguishes hyaluronate from
the other GAG’s?
What connection exists between
proteoglycans and signaling
molecules?
Extracellular Matrix – Animal Cells
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What other functions do
proteoglycans serve?
Adhesive glycoproteins (i.e.
fibronectin & laminins) also bind cells
to ECM.
Extracellular Matrix – Animal Cells
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What do we know
about fibronectins?
What does
fibronectin
structure look like?
Extracellular Matrix – Animal Cells
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What are some of the functions of
fibronectins?
Where are laminins found?
What function does the basal lamina
serve?
Extracellular Matrix – Animal Cells
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What do we know
about the structure
of laminin?
Extracellular Matrix – Animal Cells
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What are integrins?
Extracellular Matrix – Animal Cells
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What is the glycocalyx?
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What is its function?
Cell-Cell Recognition and Adhesion
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What are the
different categories
of adhesion
receptors?
What is the
difference between
homophilic and
heterophilic
interactions?
Cell-Cell Recognition and Adhesion
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What characteristics do all CAMs
share?
In what kinds of adhesion events do
the CAMs participate?
Cell-Cell Recognition and Adhesion
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How are cadherins different from
CAMs?
What types of cadherins are there?
What part of the CAM & cadherin
affects the specificity and strength of
the binding?
Cadherin Structure
Cell-Cell Recognition and Adhesion
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What are lectins?
What is the connection between red
blood cell types and carbohydrate
side chains?
How does the presence of sialic acid
groups affect the destruction of old
rbcs?
Cell Junctions
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What are cell
junctions?
What are the three
most common
types of cell
junctions?
Cell Junctions
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What do all adhesive junctions have
in common?
Where are adhesive junctions most
commonly found?
Cell Junctions
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What kinds of
proteins do all
adhesive junctions
contain?
What are
desmosomes?
Cell Junctions
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What are hemidesmosomes?
How are adherens junctions different
from desmosomes?
What is a focal contact?
Cell Junctions
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What distinguishes
a tight junction?
Where are tight
junctions found?
Cell Junctions
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What effects do these junctions have on
movement of membrane lipids and
proteins?
Cell Junctions
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What is special
about gap
junctions?
Plant Cell Surface
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What do we presently know about
the function of the cell wall?
Plant Cell Surface
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In what way is the
plant cell wall
similar to the ECM
of animal cells?
Plant Cell Surface
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How is hemicellulose different from
cellulose?
What are pectins?
Plant Cell Surface
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What makes extensins different from
pectins?
What are lignins?
Plant Cell Surface
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How is the cell wall made by the plant
cell?
Plant Cell Surface
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What are plasmodesmata?