Transcript Cell Junctions - Hudson City School District

Cell
Junctions
anchoring
Types of Cell Junctions
• In plants:
– Plasmodesmata
• In animals:
ECM (Extra-cellular Matrix)– Tight Junctions
– Anchoring Junctions
– Gap Junctions
Extracellular Matrix
• Sticky layer of glycoprotein holding cells
together
• The extracellular matrix (ECM) is the
largest component of normal skin and
gives the skin its unique properties of
elasticity, tensile strength and
compressibility.
Tight Junction
• Seals adjacent cells in a narrow band just
beneath their surface.
• No leaks.
• EX: blood vessels
Cellular
Tight
Junction
• Biomembrane II:
• Membrane Junctions
(click on review and
Then animate)
Anchoring Junctions
• Rivet cells together
with cytoskeleton
structures, but still
allow materials to
pass along the
spaces between
cells
Where found
• Where you need to handle stress
like:
–skin
–Heart
–Intestine
–Concept 4 Review:(desmosomes)
Communicating Junctions
or Gap Junctions
• permit small molecules to shuttle from one
cell to another and thus directly link the
interior of adjacent cells.
Communicating Junctions
“Gap Junctions”
• Where found:
–cardiac muscle for heartbeat
–Hormonal stimulation
–Nerves in brain release a
neurotransmitter
Gap Junctions
• Concept 4 Review: Gap Junctions (click)
Plasmodesmata
• Channels connecting PLANT CELLS
Plasmodesmata
Plasmodesmata
• Allows small
molecules
and water
to pass
between
plant cells
Can you identify the cell junctions?
Can you identify the cell junctions?
Tight junction
Anchoring
junction
Gap junction