Cell Junctions

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Cell Junctions
anchoring
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Types of Cell Junctions

• In plants
• Plasmodesmata
• In animalsECM (Extra-cellular Matrix)-
• Tight Junctions
• Anchoring Junctions
• Gap Junctions

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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.

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Tight Junction

• Seals adjacent cells in a narrow band just
  beneath their surface.
• No leaks.
• EX blood vessels

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Cellular Tight Junction

• Biomembrane II
• Membrane Junctions
• (click on review and
• Then animate)

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Anchoring Junctions

• Rivet cells together with cytoskeleton
  structures, but still allow materials to pass
  along the spaces between cells

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Where found

• Where you need to handle stress like
• skin
• Heart
• Intestine
• Concept 4 Review(desmosomes)

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Communicating Junctionsor Gap Junctions

• permit small molecules to shuttle from one cell
  to another and thus directly link the interior of
  adjacent cells.

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Communicating JunctionsGap Junctions

• Where found
• cardiac muscle for heartbeat
• Hormonal stimulation
• Nerves in brain release a neurotransmitter

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Gap Junctions

• Concept 4 Review Gap Junctions (click)

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Plasmodesmata

• Channels connecting PLANT CELLS

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Plasmodesmata
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Plasmodesmata

• Allows small molecules and water to pass between
  plant cells

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Can you identify the cell junctions?
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Can you identify the cell junctions?
Tight junction Anchoring junction Gap junction