Quiz 7-9

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(1) catalytically, (2) ATP, (3) CTP (1) allosterically, (2) CTP, (3) ATP (1) covalently, (2) ADP, (3) CDP (1) allosterically, (2) ATP, (3) CTP

(1) catalytically, (2) ATP, (3) CTP (1) allosterically, (2) CTP, (3) ATP (1) covalently, (2) ADP, (3) CDP (1) allosterically, (2) ATP, (3) CTP

Decreased fructose-2,6-bisphosphate levels. __1__ AMP is bound to the allosteric effector site and ATP is bound to the catalytic site. __2__ ATP is bound to both the catalytic site and the allosteric effector site. __2__ The conformational equilibrium is shifted toward increased amounts of the T state structure. __1__ Low energy charge in the cell. __1__ Increased fructose-2,6-bisphosphate levels. __2__ High energy charge in the cell. __1__ Increased levels of both ADP and AMP. __1__ The conformational equilibrium is shifted toward increased amounts of the R state structure. __2__ Increased citrate levels in the cell.

1. Liver PFK-1 activity is stimulated. 2. Liver PFK-1 activity is inhibited.

a metabolic pathway. a signal transduction pathway. an allosteric inhibition pathway. homeostasis.

A ligand binds to a transmembrane protein, which causes a conformational change in the protein that is detected by an intracellular protein. The intracellular protein is an enzyme that adds phosphate groups to target proteins. The phosphorylated proteins cause a physiological change within the cell. This process is an example of __________________. a metabolic pathway. a signal transduction pathway. an allosteric inhibition pathway. homeostasis.

recessive. in a tumor suppressor gene. dominant. in a gene coding a kinase. a missense mutation.

A mutation causes a cell to divide uncontrollably. Analysis of the cell shows that both copies of the gene must have the mutation. From this information, it can be determined that the mutation is ______________. Question options: recessive. in a tumor suppressor gene. dominant. in a gene coding a kinase. a missense mutation.

ATP glucose-6-P ADP fructose-6-P fructose-1,6-P

ATP glucose-6-P ADP fructose-6-P fructose-1,6-P

ATP used in the hexokinase reaction. ATP used in the phosphofructokinase reaction. Inorganic phosphate used in the phosphofructokinase reaction. Inorganic phosphate used in the glyceraldehyde-3P dehydrogenase reaction.

ATP used in the hexokinase reaction. ATP used in the phosphofructokinase reaction. Inorganic phosphate used in the phosphofructokinase reaction. Inorganic phosphate used in the glyceraldehyde-3P dehydrogenase reaction.

allosteric activator. allosteric effector. irreversible inhibitor. competitive inhibitor.

Acetylcholinesterase is an important enzyme in the nervous system. Acetylcholinesterase activity is blocked by the nerve agent sarin gas, which forms a covalent bond with a Ser in the active site of the enzyme. Sarin gas is a(n) allosteric activator. allosteric effector. irreversible inhibitor. competitive inhibitor.

allosteric effector. irreversible inhibitor. reversible inhibitor. competitive inhibitor.

Acetylcholinesterase is an important enzyme in the nervous system. Acetylcholinesterase activity is blocked by the nerve agent sarin gas, which forms a covalent bond with a Ser in the active site of the enzyme. Sarin gas is a(n)__________________. allosteric effector. irreversible inhibitor. reversible inhibitor. competitive inhibitor.

Ser Phe Thr Ser Tyr Ser Ser Tyr

An enzyme undergoes a mutation that causes it to lose the ability to be regulated via phosphorylation. Which of the following mutations may lead to this loss of regulation? Assume that the overall structure is not altered by the mutation and multiple kinases can phosphorylate the wild-type protein. Ser Phe Thr Ser Tyr Ser Ser Tyr

At equilibrium, Keq = [P]/[R] and delta G = 1, therefore delta Gº' = (1)•RT•ln Keq At equilibrium, Keq = [P]/[R] and delta G = 0, therefore delta Gº' = +RT•ln Keq At equilibrium, Keq = [R]/[P] and delta G = 0, therefore delta Gº' = -RT•ln Keq At equilibrium, Keq = [P]/[R] and delta G = 0, therefore delta Gº' = -RT•ln Keq

At equilibrium, Keq = [P]/[R] and delta G = 1, therefore delta Gº' = (1)•RT•ln Keq At equilibrium, Keq = [P]/[R] and delta G = 0, therefore delta Gº' = +RT•ln Keq At equilibrium, Keq = [R]/[P] and delta G = 0, therefore delta Gº' = -RT•ln Keq At equilibrium, Keq = [P]/[R] and delta G = 0, therefore delta Gº' = -RT•ln Keq

Because F-1P is converted to ethanol rather than being converted to DHAP and glyceraldehyde. Because F-1P cannot be metabolized, so liver cells become phosphate and ATP deficient, which causes cell death. Because F-1P is converted into fructose leading to the formation of sucrose, which is toxic to liver cells. Because F-1P is converted to F-2,6-BP, which blocks flux through the glycolytic pathway and causes cell death.

Because F-1P is converted to ethanol rather than being converted to DHAP and glyceraldehyde. Because F-1P cannot be metabolized, so liver cells become phosphate and ATP deficient, which causes cell death. Because F-1P is converted into fructose leading to the formation of sucrose, which is toxic to liver cells. Because F-1P is converted to F-2,6-BP, which blocks flux through the glycolytic pathway and causes cell death.

Because it has a low Km for glucose, which means its activity is dependent on low [glucose]. Because it has a high Km for glucose, which means its activity is dependent on high [glucose]. Because it has a low Km for glucose, which means its activity is dependent on high [glucose]. Because it is expressed in pancreas cells and not in liver cells.

Because it has a low Km for glucose, which means its activity is dependent on low [glucose]. Because it has a high Km for glucose, which means its activity is dependent on high [glucose]. Because it has a low Km for glucose, which means its activity is dependent on high [glucose]. Because it is expressed in pancreas cells and not in liver cells.

dimerization of GPCRs to form an active receptor complex. stimulation of GTPase activity in the GPCR cytoplasmic tail. activation of tyrosine kinase activity in the GPCR cytoplasmic tail recruitment of heterotrimeric G proteins to the GPCR cytoplasmic tail.

Binding of first messengers to G protein-coupled receptors results in ___________. dimerization of GPCRs to form an active receptor complex. stimulation of GTPase activity in the GPCR cytoplasmic tail. activation of tyrosine kinase activity in the GPCR cytoplasmic tail recruitment of heterotrimeric G proteins to the GPCR cytoplasmic tail.

-12.3 kJ/mol -23.3 kJ/mol +23.3 kJ/mol +11.5 kJ/mol -30 kJ/mol +12.3 kJ/mol

Calculate the actual free energy change (deltaG) for a reaction under physiological conditions (37ºC) in which the standard free energy change deltaGº' is +5.5 kJ/mol and the measured mass action ratio (Q) is 0.001. Choose the correct answer from below. Question options: -12.3 kJ/mol -23.3 kJ/mol +23.3 kJ/mol +11.5 kJ/mol -30 kJ/mol +12.3 kJ/mol

degrading key regulatory molecules. activating caspase 8. phosphorylating Fas. dephosphorylating FasL.

Caspase 3 is responsible for_______________. Question options: degrading key regulatory molecules. activating caspase 8. phosphorylating Fas. dephosphorylating FasL.

Caspases are rapidly produced by the ribosome after the signal for cell death is received. Caspases have longer stability in the cell than most proteins, since they are readily refolded by chaperones. Caspases are enzymes that function catalytically and therefore can do a lot of damage in a very short amount of time Caspases must be activated by proteolytic cleavagge to convert the inactive zymogen to the active form-this provides a means to control caspase activity by initiating the cleavage reaciton. Caspases have preferred substrate recognition sites for cleavage, and therefore can preferentially degrade other proteins

Caspases (cysteine-aspartate proteases) function as "executioners" in the cell death pathway. Choose three reasons why it makes sense that they function in this role rather than some other biomolecule. Select 3 correct answer(s) Question options: Caspases are rapidly produced by the ribosome after the signal for cell death is received. Caspases have longer stability in the cell than most proteins, since they are readily refolded by chaperones. Caspases are enzymes that function catalytically and therefore can do a lot of damage in a very short amount of time Caspases must be activated by proteolytic cleavagge to convert the inactive zymogen to the active form-this provides a means to control caspase activity by initiating the cleavage reaciton. Caspases have preferred substrate recognition sites for cleavage, and therefore can preferentially degrade other proteins

glucagon, glycolysis, gluconeogenesis, efflux glucagon, gluconeogenesis, glycolysis, efflux insulin, gluconeogenesis, glycolysis, influx insulin, glycolysis, gluconeogensis, influx glucagon, gluconeogenesis, glycolysis, influx

Choose the one answer below that contains ALL of the correct words to fill the sequential blanks in the following sentences. When blood glucose levels are high in humans, the hormone ___________ stimulates metabolic flux through the __________ pathway and inhibits flux through the __________ pathway. The net effect of this hormone signaling is to increase ___________ of glucose. glucagon, glycolysis, gluconeogenesis, efflux glucagon, gluconeogenesis, glycolysis, efflux insulin, gluconeogenesis, glycolysis, influx insulin, glycolysis, gluconeogensis, influx glucagon, gluconeogenesis, glycolysis, influx

The direction of the reaction under steady state conditions. The spontaneity of the reaction in the presence of an inhibitor. The temperature of the reaction at 1 atmosphere pressure. The actual change in free energy = 0, so it does not tell you anything. The direction of the reaction at equilibrium. The direction of the reaction at 1M substrate concentration at pH7.

Choose the statement below that best describes what the actual change in free energy (deltaG) tells you about an enzymatic reaction that cannot be determined by the standard free energy (deltaGº') change. Question options: The direction of the reaction under steady state conditions. The spontaneity of the reaction in the presence of an inhibitor. The temperature of the reaction at 1 atmosphere pressure. The actual change in free energy = 0, so it does not tell you anything. The direction of the reaction at equilibrium. The direction of the reaction at 1M substrate concentration at pH7.

formation of Schiff base intermediate substrate phosphorylatin production of endergonic intermediate cleaving of high-energy phosphate bond

Fructose-1,6-bisphosphate is cleaved by aldolase. What is required for the reaction to proceed? Question options: formation of Schiff base intermediate substrate phosphorylatin production of endergonic intermediate cleaving of high-energy phosphate bond

GRB2 is an adaptor protein that binds to EGFR through a SH2 domain and SOS protein through a PIP2 domain. GRB2 is an adaptor protein that binds to SOS protein through two SH2 domains and to Ras protein through a SH4 domain. GRB2 is an adaptor protein that binds to EGFR through a SH2 domain and to SOS protein through two SH3 domains. GRB2 is a tyrosine kinase that phosphorylates EGFR through a SH2 domain that activates the MEK pathway.

GRB2 is an adaptor protein that binds to EGFR through a SH2 domain and SOS protein through a PIP2 domain. GRB2 is an adaptor protein that binds to SOS protein through two SH2 domains and to Ras protein through a SH4 domain. GRB2 is an adaptor protein that binds to EGFR through a SH2 domain and to SOS protein through two SH3 domains. GRB2 is a tyrosine kinase that phosphorylates EGFR through a SH2 domain that activates the MEK pathway.

Fructose is a five-membered ring and glucose is a six-membered ring. Glucose is a five-membered ring and fructose is a six-membered ring. Glucose is found in the boat conformation and fructose is a chair conformation. Glucose is a linear molecule and fructose is a ring.

Glucose and fructose are both C6H12O6. What is the structural difference between them? Question options: Fructose is a five-membered ring and glucose is a six-membered ring. Glucose is a five-membered ring and fructose is a six-membered ring. Glucose is found in the boat conformation and fructose is a chair conformation. Glucose is a linear molecule and fructose is a ring.

Glucose and galactose are epimers of each other. Glucose and galactose are tetroses. Glucose and galactose are ketoses. Glucose and galactose are anomers of each other.

Glucose and galactose are epimers of each other. Glucose and galactose are tetroses. Glucose and galactose are ketoses. Glucose and galactose are anomers of each other.

His and Cys Glu and Lys Asp and His His and Lys

His and Cys Glu and Lys Asp and His His and Lys

It results in a reaction is endergonic. It produces 2 ATP along with 3-phosphoglycerate. It results in a reaction at equilibrium. It uses ATP to produce 3-phosphoglycerate. It results in a reaction at equilibrium.

How does phosphoglycerate kinase make glycolysis energy neutral at this step? Question options: It results in a reaction is endergonic. It produces 2 ATP along with 3-phosphoglycerate. It results in a reaction at equilibrium. It uses ATP to produce 3-phosphoglycerate. It results in a reaction at equilibrium.

proline-rich sequence of the SOS protein. phosphorylated Tyr of the SOS protein. protein-rich sequence of the RTK substrate. phosphorylated Tyr of the RTK substrate.

If GRB2 were truncated so that the N-terminal domain was missing, the truncated protein would be unable to bind the_________________. Question options: proline-rich sequence of the SOS protein. phosphorylated Tyr of the SOS protein. protein-rich sequence of the RTK substrate. phosphorylated Tyr of the RTK substrate.

bind CASP 8 directly. bind NFκB, even in the absence of TNF-. no longer form a trimer. bind TRADD, even in the absence of TNF- no longer be able to release TNF-.

If a mutation occurred in SODD that prohibited its interaction with the DD of TNF receptor, the TNF receptor would___________________. Question options: bind CASP 8 directly. bind NFκB, even in the absence of TNF-. no longer form a trimer. bind TRADD, even in the absence of TNF-. no longer be able to release TNF-.

Glycogen synthesis will be turned on. Glucose synthesis will be turned off. Glycogen degradation will be turned on. GLUT1 expression will be upregulated.

If protein kinase A is activated in a liver cell in response to epinephrine binding to the 2-adrenergic receptor, which of the following will result? Glycogen synthesis will be turned on. Glucose synthesis will be turned off. Glycogen degradation will be turned on. GLUT1 expression will be upregulated.

Decrease the cellular concentrations of A until the actual free energy change is now negative. The reaction cannot proceed in the forward direction under any circumstances since the standard free energy change is positive. Couple the reaction to an exergonic reaction such as ATP hydrolysis. Decrease the cellular concentration of B until the actual free energy change is now negative

If the standard free energy change for the reaction converting A to B is unfavorable, how can this reaction proceed in the forward direction under cellular conditions? Select TWO correct answers. Select 2 correct answer(s) Question options: Decrease the cellular concentrations of A until the actual free energy change is now negative. The reaction cannot proceed in the forward direction under any circumstances since the standard free energy change is positive. Couple the reaction to an exergonic reaction such as ATP hydrolysis. Decrease the cellular concentration of B until the actual free energy change is now negative

regulation of glucokinase, regulation of PFK-1, and concentration of glucose regulation of glucokinase, regulation of PFK-1, and supply and demand of intermediates regulation of glucokinase, regulation of fructokinase, and number of intermediates regulation of aldolase, regulation of PFK-1, and supply and demand of intermediates

List three ways in which flux is controlled through glycolysis. Question options: regulation of glucokinase, regulation of PFK-1, and concentration of glucose regulation of glucokinase, regulation of PFK-1, and supply and demand of intermediates regulation of glucokinase, regulation of fructokinase, and number of intermediates regulation of aldolase, regulation of PFK-1, and supply and demand of intermediates

C, B, A, D C, A, D, B C, D, A, B B, C, A, D A, B, C, D

Place the following steps in proper order: A. phosphorylation of RTK cytoplasmic tails B. activation of downstream signaling pathways C. ligand binding, receptor dimerization, and kinase activation D. protein binding to RTK phosphotyrosines and phosphorylation of target proteins Question options: C, B, A, D C, A, D, B C, D, A, B B, C, A, D A, B, C, D

__1__Phosphorylation reaction generating a hexose sugar. __8__A substrate level phosphorylation reaction generating the ATP needed to replace the ATP investment in stage 1. __7__A dehydration reaction generating a high energy phosphorylated compound. __4__Cleavage reaction converting a diphosphate sugar into two monophosphate metabolites. __3__Phosphorylation reaction converting a hexose monophosphate into a hexose bisphosphate. __6__Substrate level phosphorylation reaction generating a net yield in ATP for the glycolytic pathway. __2__An isomerization reaction converting an aldose sugar into a ketose sugar. __5__A redox reaction utilizing inorganic phosphate and a coenzyme.

Put the following glycolytic reactions in the correct order. Only 8 of the 10 reactions in the glycolytic pathway are listed, so the answer should be the relative order of the 8 reactions listed. ____Phosphorylation reaction generating a hexose sugar. ____A substrate level phosphorylation reaction generating the ATP needed to replace the ATP investment in stage 1. ____A dehydration reaction generating a high energy phosphorylated compound. ____Cleavage reaction converting a diphosphate sugar into two monophosphate metabolites. ____Phosphorylation reaction converting a hexose monophosphate into a hexose bisphosphate. ____Substrate level phosphorylation reaction generating a net yield in ATP for the glycolytic pathway. ____An isomerization reaction converting an aldose sugar into a ketose sugar. ____A redox reaction utilizing inorganic phosphate and a coenzyme.

Put the following steps of the G protein cycle into the correct order. __3__GAPs stimulate the GTPase activity of G-alpha__2__Dissociation of G-alpha and G-beta/gamma from a GPCR__1__Ligand stimulation of the GEF function of a GPCR__4__Reassociation of the heterotrimeric G complex with a GPCR

Put the following steps of the G protein cycle into the correct order. ____GAPs stimulate the GTPase activity of G-alpha____Dissociation of G-alpha and G-beta/gamma from a GPCR____Ligand stimulation of the GEF function of a GPCR____Reassociation of the heterotrimeric G complex with a GPCR

insulin; glycogen; gluconeogenesis; glucagon; glycolysis; glycogen glucagon; glycogen; gluconeogenesis; insulin; glycolysis; glycogen insulin; glycogen; glycolysis; glucagon; gluconeogenesis; glycogen glucagon; glycogen; glycolysis; insulin; gluconeogenesis; glycogen

Question options: insulin; glycogen; gluconeogenesis; glucagon; glycolysis; glycogen glucagon; glycogen; gluconeogenesis; insulin; glycolysis; glycogen insulin; glycogen; glycolysis; glucagon; gluconeogenesis; glycogen glucagon; glycogen; glycolysis; insulin; gluconeogenesis; glycogen

GAPs inhibit G proteins by stimulating GDP-GTP exchange; GEFs activate G proteins by stimulating GTP hydrolysis. GAPs stimulate G proteins by blocking GTP hydrolysis; GEFs inhibit G proteins by stimulating GTP-GDP exchange. GEFs inhibit G proteins by stimulating GTP hydrolysis; GAPs activate G proteins by stimulating GDP-GTP exchange. GAPs inhibit G proteins by stimulating GTP hydrolysis; GEFs activate G proteins by stimulating GDP-GTP exchange.

Signaling activity of G proteins is controlled by GTPase activating proteins (GAPs) and Guanine exchange factors (GEFs). What are the mechanisms by which GAPs and GEFs control G proteins? GAPs inhibit G proteins by stimulating GDP-GTP exchange; GEFs activate G proteins by stimulating GTP hydrolysis. GAPs stimulate G proteins by blocking GTP hydrolysis; GEFs inhibit G proteins by stimulating GTP-GDP exchange. GEFs inhibit G proteins by stimulating GTP hydrolysis; GAPs activate G proteins by stimulating GDP-GTP exchange. GAPs inhibit G proteins by stimulating GTP hydrolysis; GEFs activate G proteins by stimulating GDP-GTP exchange.

direct transfer of a Pi to an ADP. removal of a Pi from ATP. indirect transfer of a Pi to glucose. indirect transfer of a Pi to an ATP.

The best description of substrate-level phosphorylation is _______________. Question options: direct transfer of a Pi to an ADP. removal of a Pi from ATP. indirect transfer of a Pi to glucose. indirect transfer of a Pi to an ATP.

are only active when pairs of receptors dimerize. have a kinase domain on the intracellular side of the plasma membrane. are transmembrane proteins. contain seven transmembrane helices.

The common structural pattern that is a distinguishing characteristic specific to all G-protein-coupled receptors is that they __________________. are only active when pairs of receptors dimerize. have a kinase domain on the intracellular side of the plasma membrane. are transmembrane proteins. contain seven transmembrane helices.

__2__Insulin receptor autophosphorylates tyrosine residues in the cytoplasmic tail. __5__PI-3K binds to phosphotyrosines on IRS proteins via SH2 domains __1__Insulin binds to the insulin receptor and activates its intrinsic kinase activity. __3__IRS proteins bind to phosphotyrosines in the insulin receptor via PTB domains. _8__Akt is phosphorylated and activated by the PDK1 serine/threonine kinase activity. _7__ PDK1 and Akt bind to PIP3 in the plasma membrane via PH domains. __9__Akt dissociates from PIP3 and phosphorylates downstream target proteins. __10__Increased rates of glucose uptake and glycogen synthesis lower blood glucose. __6__PI-3K phosphorylates PIP2 to generate PIP3. __4__Insulin receptor phosphorylates IRS proteins on tyrosine residues.

The phosphoinositide-3 kinase (PI-3K) pathway is activated by insulin signaling in liver cells. Number the following statements 1-10 to order the sequence of events that lead to glucose uptake and glycogen synthesis in response to insulin signaling. The abbreviations for each signaling component of the pathway are defined in Section 8.3 of the textbook. ____Insulin receptor autophosphorylates tyrosine residues in the cytoplasmic tail. ____PI-3K binds to phosphotyrosines on IRS proteins via SH2 domains ____Insulin binds to the insulin receptor and activates its intrinsic kinase activity. ____IRS proteins bind to phosphotyrosines in the insulin receptor via PTB domains. ____Akt is phosphorylated and activated by the PDK1 serine/threonine kinase activity. ____PDK1 and Akt bind to PIP3 in the plasma membrane via PH domains. ____Akt dissociates from PIP3 and phosphorylates downstream target proteins. ____Increased rates of glucose uptake and glycogen synthesis lower blood glucose. ____PI-3K phosphorylates PIP2 to generate PIP3. ____Insulin receptor phosphorylates IRS proteins on tyrosine residues.

__3__The regulatory subunits move out of the active sites of the catalytic subunits, and the R2C2 complex dissociates.__5__Each regulatory subunit is activated as the two cAMP molecules are released.__4__The free catalytic subunits interact with proteins to phosphorylate Ser or Thr residues.__1__Cytosolic cAMP concentration increases.__2__Two cAMP molecules bind to each PKA regulatory subunit.

The second messenger cyclic AMP (cAMP) is synthesized from ATP by the activity of the enzyme adenylate cyclase. Cyclic AMP, in turn, activates proteins kinase A (PKA), which is responsible for most of the effects of cAMP within the cell. Determine the correct steps in the activation of PKA, and then number them in the correct order (1-5), starting after the adenylyl cyclase reaction. ____The regulatory subunits move out of the active sites of the catalytic subunits, and the R2C2 complex dissociates.____Each regulatory subunit is activated as the two cAMP molecules are released.____The free catalytic subunits interact with proteins to phosphorylate Ser or Thr residues.____Cytosolic cAMP concentration increases.____Two cAMP molecules bind to each PKA regulatory subunit.

Transcriptional repression of CASP8 and CASP3 gene expression to block enzyme synthesis. Inhibition of CASP3 activity by activation of CASP8 procatalytic activation. Transcriptional activation of genes encoding inhibitors of caspase enzyme activation. Activation of phosphorylation cascades that phosphorylate CASP8 to block its methylation activity.

Transcriptional repression of CASP8 and CASP3 gene expression to block enzyme synthesis. Inhibition of CASP3 activity by activation of CASP8 procatalytic activation. Transcriptional activation of genes encoding inhibitors of caspase enzyme activation. Activation of phosphorylation cascades that phosphorylate CASP8 to block its methylation activity.

Changing of the configuration of the enzyme makes the reaction exergonic. It forces covalent binding of the substrate to the enzyme active site. The induced-fit mechanism maximizes accessibility of active site without sacrificing hydrophobic environment. It allows water to be trapped in the active site along with the substrate.

What advantage is there to phosphoglycerate kinase having an open and closed configuration? Question options: Changing of the configuration of the enzyme makes the reaction exergonic. It forces covalent binding of the substrate to the enzyme active site. The induced-fit mechanism maximizes accessibility of active site without sacrificing hydrophobic environment. It allows water to be trapped in the active site along with the substrate.

Increase the affinity of PFK-1 for fructose-6-P and increase the rate of the pathway. Decrease the affinity of PFK-1 for fructose-6-P and slow rate of the pathway. Increase the concentration of glucose entering glycolysis. Increase the concentration of PFK-1 in the R-state.

What effect do elevated levels of ATP have on glycolysis? Question options: Increase the affinity of PFK-1 for fructose-6-P and increase the rate of the pathway. Decrease the affinity of PFK-1 for fructose-6-P and slow rate of the pathway. Increase the concentration of glucose entering glycolysis. Increase the concentration of PFK-1 in the R-state.

It is an adaptor protein that binds to G proteins like Ras and GSa and also to MAPK, Raf, and ERK. It is an adaptor protein that binds to phosphoserine residues in IRSs and to GEF proteins like PI-3K. It is a tyrosine kinase protein that phosphorylates arginine residues in PI-3K and in phospholipase C. It is an adaptor protein that binds to phosphotyrosine residues in RTKs and also binds to GEF proteins.

What is the function of growth factor receptor-bound 2 (GRB2) protein in RTK signaling? Question options: It is an adaptor protein that binds to G proteins like Ras and GSa and also to MAPK, Raf, and ERK. It is an adaptor protein that binds to phosphoserine residues in IRSs and to GEF proteins like PI-3K. It is a tyrosine kinase protein that phosphorylates arginine residues in PI-3K and in phospholipase C. It is an adaptor protein that binds to phosphotyrosine residues in RTKs and also binds to GEF proteins.

The GTPase synthesize cyclic GMP to regulate downstream signals. The GTPase cleaves GTP to generate GDP and activate signaling. The GTPase stimulates GDP to GTP exchange to activate signaling. The GTPase cleaves GTP to generate GDP and inactivate signaling.

What is the function of the GTPase activity in G proteins? The GTPase synthesize cyclic GMP to regulate downstream signals. The GTPase cleaves GTP to generate GDP and activate signaling. The GTPase stimulates GDP to GTP exchange to activate signaling. The GTPase cleaves GTP to generate GDP and inactivate signaling.

1st messengers bind to receptors; 2nd messengers are activated by downstream signaling events 1st messengers bind to upstream receptors; 2nd messengers bind to downstream receptors 1st messengers bind to membranes; 2nd messengers are activated by upstream signaling events 1st messengers bind to receptors; 2nd messengers are activated by upstream signaling events

What is the functional difference between a first messenger and a second messenger in cell signaling pathways? 1st messengers bind to receptors; 2nd messengers are activated by downstream signaling events 1st messengers bind to upstream receptors; 2nd messengers bind to downstream receptors 1st messengers bind to membranes; 2nd messengers are activated by upstream signaling events 1st messengers bind to receptors; 2nd messengers are activated by upstream signaling events

buildup of O2 deficiency of pyruvate buildup of glucose deficiency of ATP buildup of CO2

What would be the effect in muscle cells of a deficiency in lactate dehydrogenase? Question options: buildup of O2 deficiency of pyruvate buildup of glucose deficiency of ATP buildup of CO2

the catalytic subunit is active. it cannot bind to ATP. the catalytic subunit is inactive. the pseudosubstrate is phosphorylated. it forms a heterotrimeric complex.

When the regulatory subunit of PKA is bound to the catalytic subunit of PKA_____________. Question options: the catalytic subunit is active. it cannot bind to ATP. the catalytic subunit is inactive. the pseudosubstrate is phosphorylated. it forms a heterotrimeric complex.

cortisol, insulin, prostaglandins insulin, glucagon, glucose nitric oxide, estradiol, heme Ca2+, testosterone, protein kinase A cytochrome c, insulin, estrogen receptor

Which of the following choices below includes only first messenger signaling molecules? cortisol, insulin, prostaglandins insulin, glucagon, glucose nitric oxide, estradiol, heme Ca2+, testosterone, protein kinase A cytochrome c, insulin, estrogen receptor

The intracellular domain has phosphatase domains. The receptor contains seven alpha helices that span the membrane. A ligand binds to the extracellular domain. Ligand binding is required for autophosphorylation (cross-phosphorylation). RTKs are dimeric in the presence of ligand.

Which of the following statements accurately describe receptor tyrosine kinases (RTKs)? Select the three true statements. Select 3 correct answer(s) Question options: The intracellular domain has phosphatase domains. The receptor contains seven alpha helices that span the membrane. A ligand binds to the extracellular domain. Ligand binding is required for autophosphorylation (cross-phosphorylation). RTKs are dimeric in the presence of ligand.

adenylate cyclase cyclic UMP G-alpha subunit magnesium calcium

Which one of the following molecules can function as a second messenger? adenylate cyclase cyclic UMP G-alpha subunit magnesium calcium

insulin receptor (IR) insulin receptor substrate (IRS) phosphatase and tensin homolog (PTEN) phosphatidylinositide 3-kinase (PI-3K)

Which protein in the insulin receptor signaling pathway is capable of autophosphorylation? Question options: insulin receptor (IR) insulin receptor substrate (IRS) phosphatase and tensin homolog (PTEN) phosphatidylinositide 3-kinase (PI-3K)

2-phosphoglycerate phosphoenolpyruvate fructose-6-P fructose-1,6-BP glucose glucose-6-P glyceraldehyde-3-P 1,3-bisphosphoglycerate

Which reaction in glycolysis is a redox reaction? Question options: 2-phosphoglycerate phosphoenolpyruvate fructose-6-P fructose-1,6-BP glucose glucose-6-P glyceraldehyde-3-P 1,3-bisphosphoglycerate

combined to decrease the value of the mass action ratio Q. quickly channel from one enzyme to the next in coupled reactions. result in coupled reactions that have a positive delta Gº' value. diffuse through the membrane to increase concentration gradient.

combined to decrease the value of the mass action ratio Q. quickly channel from one enzyme to the next in coupled reactions. result in coupled reactions that have a positive delta Gº' value. diffuse through the membrane to increase concentration gradient.

protein kinase A phosphorylated GPCR ARK dephosphorylated GPCR GTP-bound

protein kinase A phosphorylated GPCR ARK dephosphorylated GPCR GTP-bound


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