Glial cells generate action potentials and carry nerve impulses between neurons.
Correct Answer
False
False. Glial cells cannot generate action potentials; they support, nourish and protect neurons. Neurons are the cells that carry nerve impulses.
Category: Neurons and Synapses
Question 2
The axon carries electrical impulses away from the neuron's cell body toward other neurons or target cells.
Correct Answer
True
True. The axon is the long extension that conducts impulses away from the cell body, while dendrites bring signals toward it.
Category: Neurons and Synapses
Question 3
The central nervous system is made up of the brain and spinal cord, while the cranial and spinal nerves outside them make up the peripheral nervous system.
Correct Answer
True
True. The CNS is the brain and spinal cord. The PNS is the network of cranial and spinal nerves outside it and is divided into the somatic and autonomic nervous systems.
Category: Nervous System Divisions
Question 4
Activation of the sympathetic nervous system causes the pupils to constrict.
Correct Answer
False
False. Sympathetic activation dilates the pupils (mydriasis) to let in more light during a threat. Pupillary constriction is a parasympathetic effect.
Category: Nervous System Divisions
Question 5
Sympathetic stimulation relaxes the urinary bladder, while parasympathetic stimulation contracts it.
Correct Answer
True
True. The sympathetic system relaxes the bladder wall so urine is held, and the parasympathetic system contracts it to empty the bladder. This is why cholinergic drugs can relieve urinary retention.
Category: Nervous System Divisions
Question 6
During the fight-or-flight response, blood flow is shunted toward skeletal muscle.
Correct Answer
True
True. Sympathetic activation redirects blood to skeletal muscle and raises heart rate and blood pressure, while digestion slows.
Category: Nervous System Divisions
Question 7
Sympathetic activation lowers blood glucose so that energy is conserved.
Correct Answer
False
False. Sympathetic activation raises blood glucose by releasing glucose from stores, providing fuel for a response to a threat.
Category: Nervous System Divisions
Question 8
Stimulation of beta3 receptors increases lipolysis, the breakdown of stored fat.
Correct Answer
True
True. Beta3 adrenergic receptors in fat tissue increase lipolysis when stimulated by norepinephrine or epinephrine.
Category: Autonomic Receptors
Question 9
Stimulation of beta2 receptors contracts bronchial smooth muscle.
Correct Answer
False
False. Beta2 stimulation relaxes bronchial smooth muscle and causes bronchodilation, which is why beta2 agonists treat asthma.
Category: Autonomic Receptors
Question 10
Stimulation of muscarinic receptors in the heart increases the heart rate.
Correct Answer
False
False. Muscarinic stimulation in the heart slows the heart rate and decreases the force of contraction, mirroring the parasympathetic system.
Category: Autonomic Receptors
Question 11
Adrenergic receptors are the receptors that respond to epinephrine and norepinephrine.
Correct Answer
True
True. Adrenergic receptors (alpha1, alpha2, beta1, beta2 and beta3) are activated by epinephrine and norepinephrine. Drugs that stimulate them are sympathomimetics.
Category: Autonomic Receptors
Question 12
Nicotinic and muscarinic receptors are both subtypes of adrenergic receptors.
Correct Answer
False
False. Nicotinic and muscarinic receptors are cholinergic receptors that respond to acetylcholine. Adrenergic receptors are the alpha and beta subtypes.
Category: Autonomic Receptors
Question 13
Postganglionic parasympathetic neurons release norepinephrine at their target organs.
Correct Answer
False
False. Postganglionic parasympathetic neurons release acetylcholine, which acts on muscarinic receptors. Norepinephrine is released by most postganglionic sympathetic neurons.
Category: Autonomic Receptors
Question 14
Acetylcholine in the synapse is broken down by the enzyme monoamine oxidase.
Correct Answer
False
False. Acetylcholine is broken down by acetylcholinesterase. Monoamine oxidase breaks down monoamines such as norepinephrine, dopamine and serotonin.
Category: Neurons and Synapses
Question 15
In a chemical synapse, an electrical signal arriving at the end of the axon triggers release of a chemical messenger into the synaptic gap.
Correct Answer
True
True. In a chemical synapse the impulse causes neurotransmitter release into the cleft, where it binds receptors on the next cell. Electrical synapses instead pass signals through direct physical connections.
Category: Neurons and Synapses
Question 16
Anticholinergic drugs are also called parasympathomimetics.
Correct Answer
False
False. Anticholinergic drugs block acetylcholine and are called parasympatholytics or cholinergic blockers. Parasympathomimetics are cholinergic agonists that mimic the parasympathetic system.
Category: Autonomic Drug Classes
Question 17
Bethanechol is contraindicated when urinary retention is caused by a mechanical obstruction.
Correct Answer
True
True. Bethanechol contracts the bladder, and contracting it against a blockage such as a urethral obstruction could cause rupture. It is used only for nonobstructive retention.
Category: Autonomic Drug Classes
Question 18
Indirect-acting cholinergic drugs work by binding directly to acetylcholine receptors.
Correct Answer
False
False. Indirect-acting cholinergic drugs inhibit acetylcholinesterase, so more acetylcholine stays in the synapse. Direct-acting drugs such as bethanechol and pilocarpine bind the receptors themselves.
Category: Autonomic Drug Classes
Question 19
Anticholinergic drugs can increase heart rate by blocking parasympathetic (vagal) input to the heart.
Correct Answer
True
True. Vagal input slows the heart through muscarinic receptors, so blocking it with a drug such as atropine raises the heart rate. This is why atropine treats symptomatic bradycardia.
Category: Autonomic Drug Classes
Question 20
Sympathomimetic drugs such as dobutamine are used short term to support cardiac output in acute heart failure and cardiogenic shock.
Correct Answer
True
True. Dobutamine stimulates beta1 receptors and increases the force of contraction, so it is used to support cardiac output in acute heart failure and cardiogenic shock. It is given IV for short-term support, not for long-term heart failure management.
Category: Autonomic Drug Classes