BIOL 3204 EXAM 2 QUESTIONS & ANSWERS
Cells that respond to signals are usually called
A) responders.
B) receivers.
C) targets.
D) contacts.
E) junctions. - Answer -C
Which is NOT a basic method of cell-to-cell communication?
A) cytoplasmic transfer of signals
B) contact-dependent signals
C) diffused chemical signals
D) nerve and blood-transported signals
E) mechanical signals - Answer -E
The most significant difference between a paracrine and an autocrine is
A) the cell that releases it.
B) the cell that responds to it.
C) the method of transport.
D) the route of transport.
E) There are no differences—they are the same. - Answer -B
Neurotransmitters and neurohormones both
A) are released by neurons.
B) affect only cells with a specific receptor.
C) travel in the blood to their target cell.
D) are released by neurons and affect only cells with specific receptors.
E) are produced by all cells. - Answer -D
Why do some normal cells fail to respond to a chemical signal?
A) Chemical signals are only delivered to specific cells.
B) Some cells lack the necessary receptors.
C) Some cells are completely without receptors.
D) Some cells are completely without ligands.
E) Signal chemicals often break down before reaching a distant target. - Answer -B
Receptor molecules on the surface of a cell
A) determine that cell's response.
B) may allow a particular ligand to bind.
C) bind to all ligands.
D) determine that cell's response and may allow a particular ligand to bind.
E) determine that cell's response and bind to all ligands. - Answer -D
Receptor molecules are located
,A) only in the outer cell membrane.
B) only in the cytosol.
C) only in the nucleus.
D) only on the cell surface.
E) in all of these places. - Answer -E
Down-regulation may allow a target cell to
A) only increase its number of receptors for a ligand.
B) only decrease its number of receptors for a ligand.
C) only increase its binding affinity for a ligand.
D) decrease the receptors' binding affinity and increase its number of receptors. -
Answer -B
Inositol triphosphate
A) is a water-insoluble messenger molecule.
B) binds to the calcium channel of the endoplasmic recticulum.
C) is involved in the release of calcium into the cytosol.
D) is a second messenger that is involved in the release of calcium into the cytosol.
E) uses all of the mechanisms. - Answer -D
Lipophilic hormones
A) bind to receptors on the surface of the cell.
B) function by way of a second messenger system.
C) cannot diffuse through the cell membrane.
D) bind to receptors inside the cytoplasm or nucleus.
E) function by activating cAMP. - Answer -D
When adenylyl cyclase is activated,
A) calcium ions are released from intracellular stores.
B) cAMP is formed.
C) cAMP is broken down.
D) protein kinases are metabolized.
E) steroids are produced. - Answer -B
Second messenger molecules directly
A) change the regulation of ion channels.
B) increase intracellular calcium concentration.
C) change enzyme activity.
D) change regulation of gene expression.
E) All of the answers are correct. - Answer -E
Cyclic AMP activates
A) a G protein.
B) adenylyl cyclase.
C) protein hormones.
D) protein kinase A.
,E) hormone receptors. - Answer -D
Diacylglycerol is produced from
A) cyclic AMP.
B) phospholipase C.
C) a G protein.
D) protein kinase A.
E) phosphatidylinositol bisphosphate. - Answer -E
Usually, cytokine binding activates
A) JAK kinase.
B) tyrosine kinase.
C) intrinsic transducers.
D) calmodulin kinase.
E) citrulline kinase. - Answer -A
What by-product results during the production of nitric oxide?
A) arginine
B) citrulline
C) nitric oxide synthase
D) carbon monoxide
E) carbon dioxide - Answer -B
An integrating center
A) is the disturbance or change that sets the pathway in motion.
B) is an electrical and/or chemical signal that travels to the effector.
C) evaluates incoming signals and compares it with the setpoint.
D) is the minimum stimulus that must be achieved to set the reflect response in motion.
- Answer -C
Which of the following are considered differences between endocrine and neural control
systems?
A) specificity
B) nature of the signal
C) speed
D) duration of action
E) All of the answers are correct. - Answer -E
Match the term with its description:
A. threshold
B. effector
C. integrating center
D. setpoint
E. sensory receptor
, the desired target value for a parameter - Answer -D
Match the term with its description:
A. threshold
B. effector
C. integrating center
D. setpoint
E. sensory receptor
receives information about the regulated variable and initiates a response - Answer -C
Match the term with its description:
A. threshold
B. effector
C. integrating center
D. setpoint
E. sensory receptor
the minimum stimulus to trigger a response - Answer -A
Match the term with its description:
A. threshold
B. effector
C. integrating center
D. setpoint
E. sensory receptor
the organ or gland that performs the change - Answer -B
Match the term with its description:
A. threshold
B. effector
C. integrating center
D. setpoint
E. sensory receptor
continuously monitors its environment for a specific variable - Answer -E
Peripheral cells sensitive to the presence of hormones are called ________. - Answer -
targets
Cells that respond to signals are usually called
A) responders.
B) receivers.
C) targets.
D) contacts.
E) junctions. - Answer -C
Which is NOT a basic method of cell-to-cell communication?
A) cytoplasmic transfer of signals
B) contact-dependent signals
C) diffused chemical signals
D) nerve and blood-transported signals
E) mechanical signals - Answer -E
The most significant difference between a paracrine and an autocrine is
A) the cell that releases it.
B) the cell that responds to it.
C) the method of transport.
D) the route of transport.
E) There are no differences—they are the same. - Answer -B
Neurotransmitters and neurohormones both
A) are released by neurons.
B) affect only cells with a specific receptor.
C) travel in the blood to their target cell.
D) are released by neurons and affect only cells with specific receptors.
E) are produced by all cells. - Answer -D
Why do some normal cells fail to respond to a chemical signal?
A) Chemical signals are only delivered to specific cells.
B) Some cells lack the necessary receptors.
C) Some cells are completely without receptors.
D) Some cells are completely without ligands.
E) Signal chemicals often break down before reaching a distant target. - Answer -B
Receptor molecules on the surface of a cell
A) determine that cell's response.
B) may allow a particular ligand to bind.
C) bind to all ligands.
D) determine that cell's response and may allow a particular ligand to bind.
E) determine that cell's response and bind to all ligands. - Answer -D
Receptor molecules are located
,A) only in the outer cell membrane.
B) only in the cytosol.
C) only in the nucleus.
D) only on the cell surface.
E) in all of these places. - Answer -E
Down-regulation may allow a target cell to
A) only increase its number of receptors for a ligand.
B) only decrease its number of receptors for a ligand.
C) only increase its binding affinity for a ligand.
D) decrease the receptors' binding affinity and increase its number of receptors. -
Answer -B
Inositol triphosphate
A) is a water-insoluble messenger molecule.
B) binds to the calcium channel of the endoplasmic recticulum.
C) is involved in the release of calcium into the cytosol.
D) is a second messenger that is involved in the release of calcium into the cytosol.
E) uses all of the mechanisms. - Answer -D
Lipophilic hormones
A) bind to receptors on the surface of the cell.
B) function by way of a second messenger system.
C) cannot diffuse through the cell membrane.
D) bind to receptors inside the cytoplasm or nucleus.
E) function by activating cAMP. - Answer -D
When adenylyl cyclase is activated,
A) calcium ions are released from intracellular stores.
B) cAMP is formed.
C) cAMP is broken down.
D) protein kinases are metabolized.
E) steroids are produced. - Answer -B
Second messenger molecules directly
A) change the regulation of ion channels.
B) increase intracellular calcium concentration.
C) change enzyme activity.
D) change regulation of gene expression.
E) All of the answers are correct. - Answer -E
Cyclic AMP activates
A) a G protein.
B) adenylyl cyclase.
C) protein hormones.
D) protein kinase A.
,E) hormone receptors. - Answer -D
Diacylglycerol is produced from
A) cyclic AMP.
B) phospholipase C.
C) a G protein.
D) protein kinase A.
E) phosphatidylinositol bisphosphate. - Answer -E
Usually, cytokine binding activates
A) JAK kinase.
B) tyrosine kinase.
C) intrinsic transducers.
D) calmodulin kinase.
E) citrulline kinase. - Answer -A
What by-product results during the production of nitric oxide?
A) arginine
B) citrulline
C) nitric oxide synthase
D) carbon monoxide
E) carbon dioxide - Answer -B
An integrating center
A) is the disturbance or change that sets the pathway in motion.
B) is an electrical and/or chemical signal that travels to the effector.
C) evaluates incoming signals and compares it with the setpoint.
D) is the minimum stimulus that must be achieved to set the reflect response in motion.
- Answer -C
Which of the following are considered differences between endocrine and neural control
systems?
A) specificity
B) nature of the signal
C) speed
D) duration of action
E) All of the answers are correct. - Answer -E
Match the term with its description:
A. threshold
B. effector
C. integrating center
D. setpoint
E. sensory receptor
, the desired target value for a parameter - Answer -D
Match the term with its description:
A. threshold
B. effector
C. integrating center
D. setpoint
E. sensory receptor
receives information about the regulated variable and initiates a response - Answer -C
Match the term with its description:
A. threshold
B. effector
C. integrating center
D. setpoint
E. sensory receptor
the minimum stimulus to trigger a response - Answer -A
Match the term with its description:
A. threshold
B. effector
C. integrating center
D. setpoint
E. sensory receptor
the organ or gland that performs the change - Answer -B
Match the term with its description:
A. threshold
B. effector
C. integrating center
D. setpoint
E. sensory receptor
continuously monitors its environment for a specific variable - Answer -E
Peripheral cells sensitive to the presence of hormones are called ________. - Answer -
targets
