Biol 1201 Final – Gregg Test Questions
with Correct/Verified Solutions 2026.
local signaling - Answer animal cells may communicate by direct contact, or cell-cell
recognition (paracrine and synaptic signaling)
cell junctions - Answer Animal and plant cells; directly connect the cytoplasm of adjacent
cells
paracrine signaling - Answer the target cells lie near the secreting cells
synaptic signaling - Answer a nerve cell releases neurotransmitter molecules into a synapse,
stimulating the target cell
endocrine (hormonal) signaling - Answer Specialized endocrine cells secrete hormones into
body fluids, often blood. Hormones reach virtually all body cells, but are bound only by some
cells.
cell-cell recognition - Answer two cells in an animal may communicate by interaction
between molecules protruding from their surfaces
three stages of cell signaling - Answer reception, transduction, response
reception - Answer The target cell's detection of a signal molecule coming from outside the
cell.
transduction - Answer the binding of the signaling molecule alters the receptor and initiates
a signal transduction pathway; occurs in a series of steps
response - Answer the transduced signal triggers a specific response in the target cell
signal transduction pathway - Answer A series of steps linking a mechanical or chemical
stimulus to a specific cellular response
ligand - Answer Signal molecule that binds to the receptor
three main types of membrane receptors - Answer -G protein-coupled receptors
, -Receptor tyrosine kinases
-Ion channel receptors
G protein-coupled receptors (GPCRs) - Answer cell-surface transmembrane receptors that
work with the help of a G protein
Receptor Tyrosine Kinases (RTKs) - Answer membrane receptors that transfer phosphate
groups from ATP to another protein
ligand-gated ion - Answer acts as a gate that opens and closes when the receptor changes
shape
intracellular receptors - Answer receptors located inside the cell rather than on its cell
membrane
phosphorylation - Answer the addition of a phosphate group to a molecule
dephosphorylation - Answer removal of a phosphate group from a molecule
second messengers - Answer Small, non-protein water soluble molecules or ions that send
messages throughout the cells by diffusion.
common second messengers - Answer cyclic AMP and calcium ions
cyclic AMP (cAMP) - Answer A compound formed from ATP that acts as a second messenger;
one of the most commonly used
adenylyl cyclase - Answer an enzyme in the plasma membrane, converts ATP to cAMP in
response to an extracellular signal
phosphorylation cascade - Answer a sequence of events where one enzyme phosphorylates
another, causing a chain reaction leading to the phosphorylation of thousands of proteins
protein phosphates - Answer Enzymes that can rapidly remove phosphate groups from
proteins.
calcium ions (Ca2+) - Answer more widely used as a second messenger than cAMP;
concentration in the cytosol is much lower than the concentration outside the cell
with Correct/Verified Solutions 2026.
local signaling - Answer animal cells may communicate by direct contact, or cell-cell
recognition (paracrine and synaptic signaling)
cell junctions - Answer Animal and plant cells; directly connect the cytoplasm of adjacent
cells
paracrine signaling - Answer the target cells lie near the secreting cells
synaptic signaling - Answer a nerve cell releases neurotransmitter molecules into a synapse,
stimulating the target cell
endocrine (hormonal) signaling - Answer Specialized endocrine cells secrete hormones into
body fluids, often blood. Hormones reach virtually all body cells, but are bound only by some
cells.
cell-cell recognition - Answer two cells in an animal may communicate by interaction
between molecules protruding from their surfaces
three stages of cell signaling - Answer reception, transduction, response
reception - Answer The target cell's detection of a signal molecule coming from outside the
cell.
transduction - Answer the binding of the signaling molecule alters the receptor and initiates
a signal transduction pathway; occurs in a series of steps
response - Answer the transduced signal triggers a specific response in the target cell
signal transduction pathway - Answer A series of steps linking a mechanical or chemical
stimulus to a specific cellular response
ligand - Answer Signal molecule that binds to the receptor
three main types of membrane receptors - Answer -G protein-coupled receptors
, -Receptor tyrosine kinases
-Ion channel receptors
G protein-coupled receptors (GPCRs) - Answer cell-surface transmembrane receptors that
work with the help of a G protein
Receptor Tyrosine Kinases (RTKs) - Answer membrane receptors that transfer phosphate
groups from ATP to another protein
ligand-gated ion - Answer acts as a gate that opens and closes when the receptor changes
shape
intracellular receptors - Answer receptors located inside the cell rather than on its cell
membrane
phosphorylation - Answer the addition of a phosphate group to a molecule
dephosphorylation - Answer removal of a phosphate group from a molecule
second messengers - Answer Small, non-protein water soluble molecules or ions that send
messages throughout the cells by diffusion.
common second messengers - Answer cyclic AMP and calcium ions
cyclic AMP (cAMP) - Answer A compound formed from ATP that acts as a second messenger;
one of the most commonly used
adenylyl cyclase - Answer an enzyme in the plasma membrane, converts ATP to cAMP in
response to an extracellular signal
phosphorylation cascade - Answer a sequence of events where one enzyme phosphorylates
another, causing a chain reaction leading to the phosphorylation of thousands of proteins
protein phosphates - Answer Enzymes that can rapidly remove phosphate groups from
proteins.
calcium ions (Ca2+) - Answer more widely used as a second messenger than cAMP;
concentration in the cytosol is much lower than the concentration outside the cell
