Communication at the Cellular Level Flashcards
when one cell sends a signal to a neighboring cell, the signaling mechanism is called
paracrine
which of the following components is the most influential factor in transmitting information from one cell to another
ligand-receptor complex
what is endocrine signaling?
cell communication by chemical signals produced by a hormone-producing gland and secreted into the bloodstream
what is paracrine signaling?
cell communication by diffusion of chemical signals from neighboring cells
what is autocrine signaling?
cell communication by diffusion of chemical signals produced and received by the same cell
which type of receptor is located inside the cell rather than in the cell membrane?
nuclear receptor
when a ligand binds to an ion-channel receptor, the channel protein opens and what is allowed to enter the cell?
ions
what is an example of a nuclear receptor ligand?
testosterone
what are 5 different effects that signal transduction can lead to?
- changes in enzyme activity
- changes in cell shape or cytoskeletal organization
- changes in ion permeability
- replication activation
- transcription activation
- controlling gene expression
Many signaling molecules are too large or otherwise unable to cross the cell membrane. Some of those molecules transmit their signal through a receptor which transmits the signal into the cell via a second messenger. The second messenger carries the information brought by the extracellular signal into the cytoplasm of the cell to generate a response. If the messenger inside the cell is the second messenger, what is the “first messenger” in a signal transduction pathway?
the signal molecules (ligand)
which term best describes the process by which an extracellular signal that does not cross the plasma membrane leads to an intracellular response?
signal transduction
GPCRs activate
G proteins
what are the 2 mechanisms that regulate the action of cAMP?
enzyme breakdown of cAMP by phosphodiesterase; inhibition of cAMP production via activation of inhibitory Ga proteins
which type of receptor requires second messengers for signal transduction?
GPCRs
what is the role of the JAK-STAT pathway
inflammation and immune responses
What is the role of the Ras-MAP pathway
cell proliferation
Imagine it is a busy Saturday morning in the clinic. Amongst your full-booked vaccination and well-check schedule, another patient is squeezed in after the customer service representative saw her rather impressive looking face. Jodi, a 3-year-old female spayed mixed breed dog was stung by a bee while out on a walk. Jodi’s face is swelling, red and itchy. You decide to give her an injection of a glucocorticoid medication, dexamethasone, for immediate relief in the hospital. What type of receptor pathway do glucocorticoid medications bind to?
nuclear receptors
The impressive sniffing ability of dogs is a result of the fact that they have almost double the number of olfactory (smelling) receptors than humans. What type of receptor do odor molecules bind to?
GPCRs
Mast cell tumors are a common skin cancer in dogs. A drug that is used to treat mast cell tumors is Palladia (toceranib). Palladia is an inhibitor class of antineoplastic (anti-cancer) drug. What kind of receptor pathway do you think is inhibited by Palladia?
enzyme-associated receptors
describe the role of a ligand in cell communication
binds to receptors and functions as a signaling molecule
what component is the most influential factor in transmitting information from one cell to another?
ligand-receptor complex
what is a characteristic of ion-channel receptors that best distinguishes them from enzyme-associated receptors?
allows passage of molecule into the cell
what molecule can serve as a second messenger?
calcium ion
what term best describes the process by which an extracellular signal that does not cross the plasma membrane leads to an intracellular response?
signal transduction
what best describes the action of opioids in regulating cAMP?
inhibition if cAMP production
