bio chapter 9 Flashcards
Which one of the following is NOT a cell surface-type receptor?
steroid receptor
What determines the specificity of a receptor protein
the ligand-binding site
Many pathologies are the result of a problem with cell signaling. Which of the following pathologies best exemplifies this fact?
Cancer, caused by a truncated receptor that is now stuck in the activated form
What does a ligand-gated channel
It allows for the movement of ions across the plasma membrane
Why dont steroid hormones bind to transmembrane cell-surface receptors?
steroid hormones are nonpolar and will cross the cell’s plasma membrane, binding to receptors inside the cell
A researcher is using a small molecule inhibitor to manipulate a signaling pathway. This inhibitor prevents phosphorylation and most likely targets a :
receptor kinase
Given that most ligands form covalent bonds with their associated receptors, these complexes are more-or-less permanent and can only be broken through the use of ATP
FALSE
Notch and Delta are both transmembrane proteins, involved in cell communication in the developing nervous system of vertebrate animals. What makes Notch different from Delta
Notch is a receptor and Delta is a signaling molecule
Which one of the following initiates signal termination
The release of signal molecules from their receptors
Which of the following is NOT a true statement about receptors that are localized to the nucleus?
They bind polar ligands
How does an “activated” receptor transfer information into the cell
through a conformation change
Why dont steroid hormones bind to transmembrane cell-surface receptors
steroid hormones are nonpolar and will cross the cells plasma membrane, binding to receptors inside the cell
Which one of the following initiates signal termination
the release of signal molecules from their receptors
Which of the following is not a true statement about receptors that are localized to the nucleus
they bind polar ligands
In cell communication, which one of the following is a requirement of the responding cell?
it must have receptor proteins
Where would you expect to find the receptor for a nonpolar ligand?
either in the nucleus of the cell or in the cytosol
To what does the term ligand refer to?
a signaling molecule
Which type of protein adds a phosphate group to another molecule
kinase
signal transduction results in:
A response by the cell
Growth factors such as platelet-derived growth factor function in:
paracrine signaling
Which of the following is NOT an essential element involved in communication between all cells?
transduction element
Which of the following is a cellular response to signal transduction
- *a change in the proteins found in the cytosol
- *the release of more cytosol signal molecules
- *a change in the activity of an enzyme
Which if the correct order for these stages in cell signaling?
receptor activation, signal transduction, response
Endocrine signaling is
Through the bloodstream far away
Autocrine signaling is
Same molecule
Paracrine symboling is
Very close molecules
Juxtacrine signaling is
Connected cells
The oxygen produced in photosynthesis comes from water, not carbon dioxide
.
