Extracellular Matrix
What does "extracellular" mean?
Outside the cell.
What are cell junctions?
Connections between neighboring cells.
What is the main purpose of adhesion junctions?
To hold cells together.
What is the main function of tight junctions?
Create an impermeable barrier between cells.
What is the main function of gap junctions?
Allow communication between cells.
What is the extracellular matrix (ECM)?
A network of molecules outside animal cells that provides support and helps cells interact with their environment.
Why do cells form junctions?
To attach cells together, create barriers, and allow communication.
Are adhesion junctions rigid or flexible?
Sturdy but flexible.
What structures are joined in tight junctions?
Adjacent plasma membranes.
How do gap junctions connect cells?
Channels in adjacent plasma membranes join together.
What is one major function of the extracellular matrix?
It provides structural support and helps cells attach to each other.
Name the three major types of cell junctions.
What do adhesion junctions create between cells?
A sturdy sheet of connected cells.
Why are tight junctions important in the intestinal wall?
They prevent unwanted substances from leaking between cells.
Why do cells need gap junctions?
To exchange signals and coordinate activities
Why is the extracellular matrix important in animal tissues?
It helps organize and support cells, allowing them to form tissues.
Which type of junction allows cells to communicate?
Gap junctions.
What structures are involved in adhesion junctions?
Internal cytoplasmic plaques joined by intercellular filaments.
What would happen if tight junctions were damaged?
Substances could pass between cells when they should not.
Which junction would a group of cells use to communicate quickly?
Gap junctions.
How does the extracellular matrix help cells survive?
It provides support and helps cells communicate with and respond to their surroundings.
Which type of junction prevents substances from passing between cells?
Tight junctions.
Why are adhesion junctions important in tissues?
They allow cells to stay connected while still allowing flexibility and movement.
Compare tight junctions and adhesion junctions.
Compare all three cell junctions.