________ is the process through which cells can detect and respond to signals in their extracellular environment.
Cell communication
Which of the following types of molecules is LEAST involved in cell communication?
carbohydrates
A substrate binds an enzyme as a signal molecule binds a
receptor
During exposure to elevated glucose, a yeast cell's membrane glucose transporters will rapidly increase so the cell can import glucose. Which would represent the yeast cell response?
both increased membrane glucose transporters and glucose transport into the cell
During exposure to elevated glucose, a yeast cell's membrane glucose transporters will rapidly increase so the cell can import glucose. Which would represent the signal for the yeast cell?
glucose
What type of cell communication is said to occur if a cell secretes a growth factor that then acts on neighboring cells to cause them to proliferate?
paracrine signaling
What type of signaling occurs when insulin is secreted from the pancreas and acts on muscle cells to increase glucose uptake?
endocrine signaling
What do we call molecules involved in long-distance signaling?
hormones
Which of the following represents a long-distance signaling mechanism?
endocrine signaling
What do synaptic signaling and paracrine signaling have in common?
Cells release a signal that affects neighboring cells.
Which of the following is not a common way signals are relayed between cells?
A. Contact-dependent signaling
B. Autocrine signaling
C. Direct intercellular signaling
D. Paracrine signaling
The KD or dissociation constant between a receptor and its hormone/ligand is
both a measure of the binding affinity the receptor has for the hormone and the hormone concentration where half the receptors are bound to hormone.
What do G-protein coupled, enzyme-linked, and ligand-gated ion channel receptors have in common?
A. They are all linked to protein kinase activation.
B. They associate with protein bound to guanidine phosphates.
C. They open ion channels.
D. They bind similar hormones.
A key is placed into a keyhole then turned and the door opens. Which of the following components of cell signaling would best correspond to turning the key?
conformational change in the receptor once bound to the hormone
A key is placed into a keyhole then turned and the door opens. Which of the following components of cell signaling would best correspond to the keyhole?
the receptor
Once bound to a hormone, this receptor becomes active and catalyzes the transfer of a phosphate group to itself or intracellular proteins.
enzyme-linked receptor
Which of the following order of events is most accurate for activation of G-protein coupled receptor (GPCR) signaling pathways?
Hormone binds GPCR, GPCR binds with G protein, G protein loses GDP and gains GTP, G-protein alpha subunit activates intracellular proteins.
Following its initial activation, how does a G protein become inactivated?
The G-protein a subunit GTP is hydrolyzed to GDP allowing reassociation of the G-protein asubunit and bgdimer.
A G-protein coupled receptor associates with a G protein that contains how many subunits?
3
Which of the following is TRUE of ligand-gated ion channels?
They open upon binding the ligand to allow specific ions to pass through them.