Test Bank Chapter 12 Biochemistry
Written by Lehninger.
Which of the following is not involved in the specificity of signal transduction?
A) Interactions between receptor and signal molecules
B) Location of receptor molecules
C) Structure of receptor molecules
D) Structure of signal molecules
E) Transmembrane transport of signal molecules by receptor molecules - Answer
Transmembrane transport of signal molecules by receptor molecules
Which of the following is not a feature of signal transduction?
A) Integration of multiple pathways toward the same downstream response
B) Signal amplification
C) Covalent binding between the ligand and the receptor
D) Desensitization or adaptation of the receptor
E) Variable affinity for different signaling components - Answer C) Covalent binding between
the ligand and the receptor
Scatchard analysis can provide information on:
A) enzyme cascades.
B) enzyme mechanisms.
C) gated ion channels.
D) protein phosphorylation.
E) receptor-ligand interactions. - Answer E) receptor-ligand interactions.
Which of the following statements concerning receptor enzymes is correct?
, E) They have an active site on the extracellular side of the membrane. - Answer B) They
contain an enzyme activity that acts on a cytosolic substrate.
Which of the following is not one of the general types of signaling mechanisms found in
multicellular organisms?
A) Gated ion channels
B) Receptor tyrosine kinases
C) G protein-coupled receptors
D) Receptor cAMP cyclases
E) Adhesion receptors - Answer D) Receptor cAMP cyclases
Which of the following is not true for G protein-coupled receptors (GPCRs)?
A) Agonists mimic the effect of the natural ligand.
B) Antagonists block the normal effect of the natural ligand.
C) GPCRs interact with heterodimeric G proteins.
D) GPCRs are have seven transmembrane helices.
E) There exist >100 orphan GPCRs in the human genome with no known ligand. - Answer C)
GPCRs interact with heterodimeric G proteins.
Cholera and pertussis toxins are:
A) enzyme inhibitors.
B) enzyme modifiers.
C) enzymes.
D) G protein signal transduction disrupters.
E) All of the above - Answer E) All of the above
Protein kinase A (PKA) is:
A) activated by covalent binding of cyclic AMP.
Written by Lehninger.
Which of the following is not involved in the specificity of signal transduction?
A) Interactions between receptor and signal molecules
B) Location of receptor molecules
C) Structure of receptor molecules
D) Structure of signal molecules
E) Transmembrane transport of signal molecules by receptor molecules - Answer
Transmembrane transport of signal molecules by receptor molecules
Which of the following is not a feature of signal transduction?
A) Integration of multiple pathways toward the same downstream response
B) Signal amplification
C) Covalent binding between the ligand and the receptor
D) Desensitization or adaptation of the receptor
E) Variable affinity for different signaling components - Answer C) Covalent binding between
the ligand and the receptor
Scatchard analysis can provide information on:
A) enzyme cascades.
B) enzyme mechanisms.
C) gated ion channels.
D) protein phosphorylation.
E) receptor-ligand interactions. - Answer E) receptor-ligand interactions.
Which of the following statements concerning receptor enzymes is correct?
, E) They have an active site on the extracellular side of the membrane. - Answer B) They
contain an enzyme activity that acts on a cytosolic substrate.
Which of the following is not one of the general types of signaling mechanisms found in
multicellular organisms?
A) Gated ion channels
B) Receptor tyrosine kinases
C) G protein-coupled receptors
D) Receptor cAMP cyclases
E) Adhesion receptors - Answer D) Receptor cAMP cyclases
Which of the following is not true for G protein-coupled receptors (GPCRs)?
A) Agonists mimic the effect of the natural ligand.
B) Antagonists block the normal effect of the natural ligand.
C) GPCRs interact with heterodimeric G proteins.
D) GPCRs are have seven transmembrane helices.
E) There exist >100 orphan GPCRs in the human genome with no known ligand. - Answer C)
GPCRs interact with heterodimeric G proteins.
Cholera and pertussis toxins are:
A) enzyme inhibitors.
B) enzyme modifiers.
C) enzymes.
D) G protein signal transduction disrupters.
E) All of the above - Answer E) All of the above
Protein kinase A (PKA) is:
A) activated by covalent binding of cyclic AMP.
