BIO 411 EXAM 4 QUESTIONS AND ANSWERS
LATEST UPDATE 2026/2027 | 100% VERIFIED |
GRADED A+.
What does Cell signaling require? - ANSWER Signaling Cell,
Signaling
molecule, responding cell, and
receptor.
Four Steps of Cell Signaling - ANSWER receptor
activation, signal
transduction, cellular response, and signal
termination.
Autocrine Signaling - ANSWER occurs when the same cell
makes and
responds to the
signal
Contact-Dependent Signaling - ANSWER signaling between two
touching
cells
Signaling Molecule - ANSWER ligand; receptor binding site =
ligand-binding
site
Receptors - ANSWER Exist as either 'on' or 'off'
Intracellular Receptors - ANSWER reside inside the cell and bind
ligands that can pass through the plasma membrane. Some are in the
nucleus and regulate transcription.
, Cell Surface Receptors - ANSWER typically bind polar molecules
since they
can't pass through the plasma
membrane
An Indivdual Cell - ANSWER Can have thousands of different
receptors
Endocrine Signaling - ANSWER long distance, uses the circulatory
system
Paracrine Signaling - ANSWER close distance
Surface Receptor Categories - ANSWER G-protein coupled receptors,
receptor
kinases, and ligand-gated ion
channels.
G-Protein Coupled Receptors - ANSWER receptor that: interacts
with g proteins on the membrane, has three subunits (Alpha, Beta and
Gamma), are active with GTP bound and inactive with GDP bound,
subunits join together when GDP is bound ect.
Ligand-Gated Ion Channels - ANSWER a channel that allows ions
through the
plasma membrane remain closed until a ligand binds and opens the
channel.
Some are activated by voltage changes across
membranes
Ras Mutations - ANSWER account for ~30% of all human cancers
G Protein - ANSWER Bind the guanine nucleotides GDP and GTP.
LATEST UPDATE 2026/2027 | 100% VERIFIED |
GRADED A+.
What does Cell signaling require? - ANSWER Signaling Cell,
Signaling
molecule, responding cell, and
receptor.
Four Steps of Cell Signaling - ANSWER receptor
activation, signal
transduction, cellular response, and signal
termination.
Autocrine Signaling - ANSWER occurs when the same cell
makes and
responds to the
signal
Contact-Dependent Signaling - ANSWER signaling between two
touching
cells
Signaling Molecule - ANSWER ligand; receptor binding site =
ligand-binding
site
Receptors - ANSWER Exist as either 'on' or 'off'
Intracellular Receptors - ANSWER reside inside the cell and bind
ligands that can pass through the plasma membrane. Some are in the
nucleus and regulate transcription.
, Cell Surface Receptors - ANSWER typically bind polar molecules
since they
can't pass through the plasma
membrane
An Indivdual Cell - ANSWER Can have thousands of different
receptors
Endocrine Signaling - ANSWER long distance, uses the circulatory
system
Paracrine Signaling - ANSWER close distance
Surface Receptor Categories - ANSWER G-protein coupled receptors,
receptor
kinases, and ligand-gated ion
channels.
G-Protein Coupled Receptors - ANSWER receptor that: interacts
with g proteins on the membrane, has three subunits (Alpha, Beta and
Gamma), are active with GTP bound and inactive with GDP bound,
subunits join together when GDP is bound ect.
Ligand-Gated Ion Channels - ANSWER a channel that allows ions
through the
plasma membrane remain closed until a ligand binds and opens the
channel.
Some are activated by voltage changes across
membranes
Ras Mutations - ANSWER account for ~30% of all human cancers
G Protein - ANSWER Bind the guanine nucleotides GDP and GTP.
