Cell Physiology
Thought Questions for Exam 2
1. Why are there
so many types of cell-to-cell and cell-to-matrix interaction? What is the function of each type? What would happen if one or two types were
missing? Are these interactions specific
for different types of cell or are they found in all eukaryotic cells?
2. What two
families of proteins are absolutely essential for cell-cell and cell-matrix
interactions? What are specific examples
of each family that are involved with the various types of interactions? Which example is an integral membrane protein
and which is a peripheral membrane protein?
3. For cells in culture, how does focal contact affect
cell proliferation?
4. What is the
advantage of having one kinase receptor being able to
activate multiple pathways?
5. How are cell
in culture induced to grow? Discuss all
pathways that are involved (that are discussed in class so far).
6. What are the
functions of: Ion-channel receptor,
G-protein-linked receptor, Kinase receptor, and Kinase-linked receptor?
What is/are the ultimate goal of pathways that activated by these
receptors? How are these receptors
controlled/activated? How do these
various pathways interact with one another?
7. Why are there so many steps and regulations
during the MAP kinase signal transduction
pathway? What is the function of each
protein or enzyme? What might happen if one were missing? What is the function of GAP? Why is this function necessary? What might happen to the cell if GAP were
missing?
8. What
processes or pathways are affected if all G proteins (or GTPase)
are rendered nonfunctional? Why? Is there any way to get around this
problem? What is the difference between
phosphorylation and an exchange of GDP for GTP?
9. How
does a cell know when to perform a particular function?
10. How
do the various signal transduction pathways interact with one another? Why do they interact with one another?
11. What is the function these processes: dimerization of a
membrane receptor, hydrolysis of GTP, and autophosphorylation
of the EGF receptor dimer.
12. What are the different ways that one cell can
communicate with another cell? What are
the different types of molecule required for the communication? How does a target
cell process information received from a signaling cell? What do these target cells actually do after
receiving these signals?