Download Chapter 11: Cell-Cell Interactions (Lectures 16-18)

Chapter 11: Cell-Cell Interactions (Lectures 16-18)
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 16 “Cell Communication I” Review:
1.) In regards to slide 5 on Dr. Hinton lecture—Which signal molecule is lipid soluble? What would
be the properties of each molecule causing their current positioning/interaction?
2.) If a signal molecule was sent out from brain cells to all other cells in the body with the
“message” of signaling for dehydration and therefore to conserve water in cells, would all cells
in the body respond to this “message”? Make sure you can explain (not just yes or no).
3.) What are two outcomes of receptors responding to intensive hormonal stimulation for a
prolonged period of time? (p. 210 in text) What property of receptors is demonstrated by the
action of a beta-blocker or caffeine (only the property here is important not ex. Unless you’re
premed!)
4.) What happens to a signal receptor when a signal molecule binds to it?
5.) What is signal transduction? What is a second messenger?
6.) How does signal processing differ for lipid-soluble signals versus lipid-insoluble signals?
7.) What occurs with signal amplification?
8.) Compare and contrast the two signaling mechanisms on slide 10 of Hinton lecture. Make sure
you can distinguish between a kinase and a phosphatase at this point (fully understand this—it’s
a building block for cell signaling)
9.) What does RTK stand for? What type of signal transduction occurs in the RTK pathway?
10.) Outline the steps of the RTK signaling pathway. Include the point at which the receptor becomes
active.
11.) What type of protein inactivates the phosphorylation cascade occurring in the RTK-MAPK
pathway (signal deactivation)?
12.) How does the GPCR (G-protein coupled receptor) pathway differ from the RTK pathway? (text p.
212)
I spoke with Dr. Allison and she’s informed me that it’s unlikely that information about MK-STYX will be
on the exam
Lecture 17 “Cell Communication II” 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 18 “Cell Communication III” Review:
There wasn’t too much new material here. The only thing I would review is quorum sensing since we
spent the most time on it (p. 216 in text). Watch the video from lecture again about quorum sensing.
Other than that, review lecture 16, since we reviewed the steps involved in signal transduction in this
lecture as well. The in-class assignment for cell communication would be effective—the yeast example
came from section 11.4 in the text.