Download Cell-Cell Interactions (Lectures 22-23)

Cell-Cell Interactions (Lectures 22-23)
Text Vocabulary:
Primary Cell Wall
Microfibrils
Pectins
Turgor Pressure
Expansins
Secondary Cell Wall
Lignin
Extracellular Matrix (ECM)
Collagen
Proteoglycans
Integrins
Laminins
Epithelium
Selective Adhesion
Tight Junction
Desmosomes
Antibody
Cadherins
Gap Junctions
Plasmodesmata
Symplast
Apoplast
Hormones
Signal Transduction
G Proteins
Protein Kinases
Receptor Tyrosines Kinases
(RTKs)
Phosphorylation Cascade
Mitogen-activated Protein
Kinases (MAPK)
Phosphatases
Crosstalk
Pheromones
Quorum Sensing
Lecture 22 “Cell-Cell Interactions: Communication between Adjacent Cells” PPT Review:
1.) What general forces does the extracellular matrix of cells protect against?
2.) What is the primary cell wall composed of? What type of macromolecule is this? How is it
packaged and arranged in the cell wall? What molecule fills the space between this cell wall
material and what type of macromolecule is this?
3.) What material makes up the “cross-linked filaments” of plant cell ECM? Ground substance?
4.) What is turgor pressure?
5.) In regards to composition, what is the difference between plant ECM and animal ECM? What
makes up the fibrous component of animal ECM? What type of macromolecule is this? What
makes up the matrix that surrounds the fibrous component?
6.) Where are most ECM components synthesized in animal cells? Where are they processed? How
are they secreted from the cell?
7.) What will dictate variation in both the amount of and composition of ECM in animals?
8.) Why are integrins an important protein for cell-cell interaction?
9.) What is the example we discussed that demonstrates one possibility of cells losing their cellECM connection
10.) Describe tight junctions. If a line of cells connected by tight junctions were to come in contact
with a solution, how would the solution cross beyond the barrier of cells?—Why is this
important?
11.) What is selective adhesion? What type of cell adhesion proteins did we discuss in lecture?
Where are these proteins found? What is their significance?
12.) Adjacent cells have specializes proteins that assemble in their membranes which form structures
that allow a channel to form and thus serve as communication portals. What is the name of
these structures in animal cells? What are they in plant cells? What type of molecules would
pass through these channels?
Lecture 23 “How Cells Communicate: Communication between Distant Cells” PPT Review
1.) What is a hormone? Examples of hormones from PPT?
2.) Describe signal receptors and how they respond to their corresponding ligand. How do signal
receptors serve as a control mechanism for determining the functionality of cells?
3.) Explain why there are both intracellular and extracellular receptors.
4.) If the signaling molecular is lipid-insoluble, how is the signal transmitted to the cell? What are
the two types of receptors for lipid-insoluble molecules?
5.) Outline the general steps of a signal transduction pathway.
6.) Outline the steps of the GPCR signaling pathway.
7.) Explain the significance of primary signaling messengers leading to secondary messengers?
8.) Outline the steps of an enzyme-linked receptor signaling pathway (the book uses a receptor
tyrosine kinase (RTK) pathway to describe this.
9.) Keep in mind that signal deactivation is crucial for the cell to continue proper functioning. Based
on the types of enzymes present in the RTK pathway example, what type of enzyme could
interact with the pathway to largely deactivate the signal transduction?