BMB 252 Exam 1 Questions and
Answers 100% Solved | Latest Update
what binds to an extracellular signal - ✔✔receptor
some signal transduction proteins are similar/homologous in yeast and
humans - ✔✔true
what are signaling molecule examples - ✔✔CO, nucleotide, steriod,
neurotransmitter
some signaling molecules can travel through the cellular membrane and
bind to their targets inside the cell - ✔✔true
what signaling types can be used to guide cell movement - ✔✔paracrine
and contact dependent
lymphocytes have receptors for their own signals that result in their self
activation as well; this type of signaling is called - ✔✔autocrine
neurotransmitters have higher affinity to their receptors than hormones -
✔✔false
if a cell recieves no signal, it will die - ✔✔true
,which signal is transduced faster - ✔✔the one that changes the protein
modification state
acetylcholine always causes muscles to contract - ✔✔false
acetylcholines binds to only one kind of receptor - ✔✔false
ion pumps pump signals back into what to clear the synapse - ✔✔the
presynaptic cell
what is irreversible: receptor sequestration or down-regulation? -
✔✔sequestration
which feedback loop can result in oscillation? - ✔✔negative
which of the following can diffuse freely through the plasma membrane and
does not require channels? CO2, H20, K+ - ✔✔CO2
autocrine signaling is analagous to - ✔✔talking to yourself
which of the receptors have the lowest affinity to their signaling molecules -
✔✔acetylcholine receptors in the synapse
maintaining constant protein expression throughout the lifetime is based on
what - ✔✔positive feedback loops
ion channel linked receptors are mostly located on - ✔✔at synapses on
postsynaptic neurons
, phosphorylation of an enzyme always turns it on - ✔✔false
GPCR is a GEF for G protein - ✔✔true
what happens to a cell in the absence of a signal - ✔✔apoptosis-
programmed cell death
What keeps the signal localized in paracrine signaling? - ✔✔they can
quickly be absorbed by other cells, get degraded by extracellular enzymes,
and get trapped in extracellular matrix
what kinds of molecules can act as signals - ✔✔proteins, small peptides,
amino acids, nucleotides, steroids, retinoids, fatty acid derivatives,
dissolved gases (CO, NO)
difference between signaling molecules that bind to intracellular and cell-
surface receptors? - ✔✔cell surface signals= hydrophillic; intracellular=
hydrophobic (must pass through lipid bilayer)
four forms of intercellular signaling - ✔✔contact-dependent, paracrine,
endocrine, synaptic
synaptic vs. endocrine signaling - ✔✔endocrine= slow signal
delivery/diffusion, low concentration of signal (hormones are in low
concentration in the blood), high affinity for receptors; synaptic= fast signal
delivery/diffusion, high concentration of signal (lots of neurotransmitters at
Answers 100% Solved | Latest Update
what binds to an extracellular signal - ✔✔receptor
some signal transduction proteins are similar/homologous in yeast and
humans - ✔✔true
what are signaling molecule examples - ✔✔CO, nucleotide, steriod,
neurotransmitter
some signaling molecules can travel through the cellular membrane and
bind to their targets inside the cell - ✔✔true
what signaling types can be used to guide cell movement - ✔✔paracrine
and contact dependent
lymphocytes have receptors for their own signals that result in their self
activation as well; this type of signaling is called - ✔✔autocrine
neurotransmitters have higher affinity to their receptors than hormones -
✔✔false
if a cell recieves no signal, it will die - ✔✔true
,which signal is transduced faster - ✔✔the one that changes the protein
modification state
acetylcholine always causes muscles to contract - ✔✔false
acetylcholines binds to only one kind of receptor - ✔✔false
ion pumps pump signals back into what to clear the synapse - ✔✔the
presynaptic cell
what is irreversible: receptor sequestration or down-regulation? -
✔✔sequestration
which feedback loop can result in oscillation? - ✔✔negative
which of the following can diffuse freely through the plasma membrane and
does not require channels? CO2, H20, K+ - ✔✔CO2
autocrine signaling is analagous to - ✔✔talking to yourself
which of the receptors have the lowest affinity to their signaling molecules -
✔✔acetylcholine receptors in the synapse
maintaining constant protein expression throughout the lifetime is based on
what - ✔✔positive feedback loops
ion channel linked receptors are mostly located on - ✔✔at synapses on
postsynaptic neurons
, phosphorylation of an enzyme always turns it on - ✔✔false
GPCR is a GEF for G protein - ✔✔true
what happens to a cell in the absence of a signal - ✔✔apoptosis-
programmed cell death
What keeps the signal localized in paracrine signaling? - ✔✔they can
quickly be absorbed by other cells, get degraded by extracellular enzymes,
and get trapped in extracellular matrix
what kinds of molecules can act as signals - ✔✔proteins, small peptides,
amino acids, nucleotides, steroids, retinoids, fatty acid derivatives,
dissolved gases (CO, NO)
difference between signaling molecules that bind to intracellular and cell-
surface receptors? - ✔✔cell surface signals= hydrophillic; intracellular=
hydrophobic (must pass through lipid bilayer)
four forms of intercellular signaling - ✔✔contact-dependent, paracrine,
endocrine, synaptic
synaptic vs. endocrine signaling - ✔✔endocrine= slow signal
delivery/diffusion, low concentration of signal (hormones are in low
concentration in the blood), high affinity for receptors; synaptic= fast signal
delivery/diffusion, high concentration of signal (lots of neurotransmitters at
