Week Two Flashcards
Neurons conduct an action potential down the axon and transmit information across the synapse to the post-synaptic cell. This information is received by:
A) The cell body
B) Dendrites
C) Receptors
D) Axons
Correct Answer: C) Receptors
Rationale: The post-synaptic cell receives signals through receptors that bind neurotransmitters released into the synaptic cleft.
Drugs can influence neuronal activity by impacting either:
A) Axonal conduction or synaptic transmission
B) Synapse reuptake or synapse breakdown
C) Dendritic growth or axonal shrinkage
D) Myelination or synaptic pruning
Answer: A) Axonal conduction or synaptic transmission
Rationale: Drugs may affect how action potentials are conducted down the axon (axonal conduction) or how neurotransmitters are transmitted across the synapse (synaptic transmission).
When a drug increases activation of a receptor, it likely:
A) Blocks the neurotransmitter
B) Decreases receptor sensitivity
C) Mimics or enhances the neurotransmitter
D) Inhibits neurotransmitter release
Answer: C) Mimics or enhances the neurotransmitter
Rationale: Drugs that increase receptor activation either mimic the neurotransmitter or enhance its action, leading to increased receptor activity.
A drug that decreases activation of a receptor might work by:
A) Inhibiting receptor binding
B) Increasing neurotransmitter production
C) Mimicking a decrease in neurotransmitter activity
D) Facilitating synaptic transmission
Answer: C) Mimicking a decrease in neurotransmitter activity
Rationale: Drugs that decrease receptor activation often act as antagonists, either blocking the receptor or mimicking a reduction in neurotransmitter availability or activity.
Receptor selectivity refers to the ability of drugs to:
A) Affect all biological processes equally
B) Target specific disease processes while leaving others unaffected
C) Increase the number of available receptors
D) Completely inhibit all receptor activity
Answer: B) Target specific disease processes while leaving others unaffected
Rationale: Receptor selectivity allows drugs to manipulate specific biological processes without affecting others, reducing side effects and increasing therapeutic effectiveness.
If drugs acted on the same receptor type for all processes, what would be the likely outcome?
A) Improved efficacy for all diseases
B) Targeted therapy for specific conditions
C) Widespread effects on multiple processes
D) Reduced drug interactions
Answer: C) Widespread effects on multiple processes
Rationale: If drugs did not have different receptor types to target, they would indiscriminately affect all processes mediated by that receptor, leading to unwanted side effects.
The presence of different receptors can:
A) Increase the dosage of drugs
B) Create drugs that can cure all diseases
C) Selectively manipulate specific processes
D) Avoid the use of any medications
Answer: C) Selectively manipulate specific processes
Rationale: Different receptors enable the design of drugs that can specifically target and alter certain physiological processes without impacting others, improving treatment precision.
Which of the following statements about receptor selectivity is true?
A) All drugs work on every type of receptor in the body.
B) Receptor selectivity enhances the therapeutic index of a drug.
C) Lack of receptor selectivity results in fewer side effects.
D) Receptor selectivity is irrelevant to drug design.
Answer: B) Receptor selectivity enhances the therapeutic index of a drug.
Rationale: Receptor selectivity improves the therapeutic index by allowing drugs to effectively treat specific conditions while minimizing adverse effects on other processes.
Most structures in the body receive innervation from both the sympathetic nervous system (SNS) and the parasympathetic nervous system (PSNS), except for which of the following?
A) Heart
B) Digestive organs
C) Adrenal medulla
D) Sweat glands
Answer: C) Adrenal medulla
Rationale: The adrenal medulla is innervated solely by the sympathetic nervous system, which stimulates the release of hormones like adrenaline.
The sympathetic nervous system (SNS) and parasympathetic nervous system (PSNS) often have what type of relationship?
A) They work in harmony to enhance the same processes.
B) They independently regulate all bodily functions.
C) They oppose each other to maintain homeostasis.
D) They exclusively enhance physiological processes.
Answer: C) They oppose each other to maintain homeostasis.
Rationale: The SNS and PSNS often have opposing effects on the same organs, which helps regulate physiological processes and maintain homeostasis.
Regulation of physiological processes is often achieved through:
A) Continuous electrical stimulation
B) Hormonal feedback loops only
C) Feedback loops involving receptors like baroreceptors
D) Sole reliance on the endocrine system
Regulation of physiological processes is often achieved through:
A) Continuous electrical stimulation
B) Hormonal feedback loops only
C) Feedback loops involving receptors like baroreceptors
D) Sole reliance on the endocrine system
Autonomic tone refers to the “baseline” level of activity in the autonomic nervous system. Which branch is primarily responsible for managing this tone?
A) Sympathetic nervous system
B) Central nervous system
C) Parasympathetic nervous system
D) Somatic nervous system
Answer: C) Parasympathetic nervous system
Rationale: The PSNS often manages the autonomic tone, maintaining a baseline level of activity that promotes restful and restorative functions in the body.
Which of the following is NOT maintained by the parasympathetic nervous system (PSNS)?
A) Heart rate reduction
B) Gastrointestinal motility enhancement
C) Blood vessel constriction
D) Salivation
Answer: C) Blood vessel constriction
Rationale: Blood vessel constriction is primarily mediated by the sympathetic nervous system (SNS), while the PSNS generally promotes vasodilation and relaxation of blood vessels.
In the parasympathetic nervous system (PSNS), how many neurons are typically involved in the pathway from the spinal cord to the target organs?
A) One neuron
B) Two neurons
C) Three neurons
D) Four neurons
Answer: B) Two neurons
Rationale: The PSNS utilizes a two-neuron pathway, consisting of a preganglionic neuron and a postganglionic neuron, with a synapse occurring at a ganglion.
he junction between the two neurons in the parasympathetic nervous system pathway is known as:
A) Synapse
B) Dendrite
C) Soma
D) Axon
Answer: A) Synapse
Rationale: The junction where the preganglionic and postganglionic neurons meet is called a synapse, specifically at a ganglion in the PSNS.
In the sympathetic nervous system (SNS), what unique pathway is present that is not found in the parasympathetic nervous system?
A) Direct connection to the spinal cord
B) A pathway involving the adrenal medulla
C) Multiple synapses in the ganglia
D) One-neuron pathway
Answer: B) A pathway involving the adrenal medulla
Rationale: The SNS has a unique pathway that includes the adrenal medulla, which acts as a postganglionic neuron, releasing hormones like epinephrine and norepinephrine into the bloodstream.
Which of the following statements is true regarding the somatic nervous system?
A) It utilizes two neurons to communicate with organs.
B) It involves a ganglion between the spinal cord and target organs.
C) It only has one neuron in its pathway.
D) It can have multiple sites of action for drugs.
Correct Answer: C) It only has one neuron in its pathway.
Rationale: The somatic nervous system consists of a single neuron that directly innervates skeletal muscle, unlike the ANS, which involves multiple neurons and ganglia.
When discussing drug action in the somatic nervous system, what is true regarding the sites of action?
A) Drugs have multiple sites of action.
B) Drugs have a single site of action.
C) Drugs can act on both preganglionic and postganglionic neurons.
D) Drug action is not relevant in the somatic nervous system.
Answer: B) Drugs have a single site of action.
Rationale: In the somatic nervous system, drugs typically have one site of action, as they interact with the motor neurons that directly control muscle contractions.
Which neurotransmitter is released by all preganglionic and postganglionic neurons of the parasympathetic nervous system (PSNS)?
A) Norepinephrine (NE)
B) Epinephrine (EPI)
C) Acetylcholine (ACh)
D) Dopamine
Answer: C) Acetylcholine (ACh)
Rationale: Acetylcholine (ACh) is the neurotransmitter released by all preganglionic and postganglionic neurons of the PSNS.
What neurotransmitter do all preganglionic neurons of the sympathetic nervous system (SNS) release?
A) Norepinephrine (NE)
B) Epinephrine (EPI)
C) Acetylcholine (ACh)
D) Serotonin
Answer: C) Acetylcholine (ACh)
Rationale: All preganglionic neurons of the SNS release acetylcholine (ACh) before synapsing with postganglionic neurons.
Most postganglionic neurons of the sympathetic nervous system (SNS) release which of the following neurotransmitters?
A) Acetylcholine (ACh)
B) Dopamine
C) Epinephrine (EPI)
D) Norepinephrine (NE)
Answer: D) Norepinephrine (NE)
Rationale: Most postganglionic neurons of the SNS release norepinephrine (NE), except those that innervate sweat glands.
Which neurotransmitter is specifically released by the adrenal medulla into the bloodstream?
A) Acetylcholine (ACh)
B) Norepinephrine (NE)
C) Epinephrine (EPI)
D) Gamma-aminobutyric acid (GABA)
Answer: C) Epinephrine (EPI)
Rationale: The adrenal medulla releases epinephrine (EPI), which acts as a hormone and neurotransmitter in the body.
Which of the following statements is true regarding the neurotransmitters of the sympathetic nervous system (SNS)?
A) All postganglionic neurons release acetylcholine (ACh).
B) Postganglionic neurons that innervate sweat glands release norepinephrine (NE).
C) Preganglionic neurons release epinephrine (EPI).
D) Most postganglionic neurons release norepinephrine (NE), except those for sweat glands.
Answer: D) Most postganglionic neurons release norepinephrine (NE), except those for sweat glands.
Rationale: Most postganglionic neurons in the SNS release norepinephrine (NE), while postganglionic neurons that target sweat glands release acetylcholine (ACh).
Where are Nicotinic N receptors primarily located?
A) On the surface of skeletal muscle cells
B) In the cell bodies of post-ganglionic neurons in both the sympathetic nervous system (SNS) and parasympathetic nervous system (PSNS)
C) In the brain only
D) On the adrenal cortex
Answer: B) In the cell bodies of post-ganglionic neurons in both the sympathetic nervous system (SNS) and parasympathetic nervous system (PSNS)
Rationale: Nicotinic N receptors are found on the cell bodies of post-ganglionic neurons in both the SNS and PSNS, facilitating ganglionic transmission.
What is one of the primary functions of Nicotinic N receptors?
A) Inhibit neurotransmitter release
B) Promote ganglionic transmission in all ganglia of the SNS and PSNS
C) Decrease heart rate
D) Cause bronchoconstriction
Answer: B) Promote ganglionic transmission in all ganglia of the SNS and PSNS
Rationale: Nicotinic N receptors facilitate ganglionic transmission in both the SNS and PSNS, ensuring effective communication between pre- and post-ganglionic neurons.
Nicotinic N receptors also promote the release of which neurotransmitter from the adrenal medulla?
A) Acetylcholine (ACh)
B) Norepinephrine (NE)
C) Epinephrine (EPI)
D) Serotonin
Answer: C) Epinephrine (EPI)
Rationale: Activation of Nicotinic N receptors promotes the release of epinephrine (EPI) from the adrenal medulla into the bloodstream.
The stimulation of Nicotinic N receptors can lead to which of the following outcomes?
A) Decreased sympathetic activity
B) Enhanced ganglionic transmission and increased adrenal hormone release
C) Blockade of parasympathetic activity
D) Inhibition of skeletal muscle contraction
Answer: B) Enhanced ganglionic transmission and increased adrenal hormone release
Rationale: The activation of Nicotinic N receptors enhances ganglionic transmission and promotes the release of adrenal hormones like epinephrine.
Which of the following best describes the role of Nicotinic N receptors in the autonomic nervous system?
A) They inhibit neuronal communication.
B) They facilitate communication between pre- and post-ganglionic neurons.
C) They only affect the sympathetic nervous system.
D) They are primarily located in the peripheral nervous system.
Answer: B) They facilitate communication between pre- and post-ganglionic neurons.
Rationale: Nicotinic N receptors are crucial for promoting ganglionic transmission in both the SNS and PSNS, facilitating effective neuronal communication.
What are the Cholinergic receptor subtypes?
Nicotinic M
Nicotinic N
Muscarinic
What can activate all three subtypes of cholinergic receptors?
Acetylcholine ACh
Where are Nicotinic M receptors primarily located?
A) Heart tissue
B) Smooth muscle
C) Skeletal muscle
D) Neurons in the brain
Answer: C) Skeletal muscle
Rationale: Nicotinic M receptors are specifically located at the neuromuscular junction in skeletal muscle, where they mediate muscle contraction.
What is the primary function of Nicotinic M receptors?
A) Inhibition of skeletal muscle contraction
B) Stimulation of cardiac output
C) Contraction of skeletal muscle
D) Regulation of smooth muscle tone
Answer: C) Contraction of skeletal muscle
Rationale: The primary function of Nicotinic M receptors is to mediate the contraction of skeletal muscle upon activation by acetylcholine.
Activation of Nicotinic M receptors leads to which of the following outcomes?
A) Relaxation of skeletal muscle
B) Increased secretion of epinephrine
C) Initiation of skeletal muscle contraction
D) Inhibition of ganglionic transmission
Answer: C) Initiation of skeletal muscle contraction
Rationale: When Nicotinic M receptors are activated by acetylcholine, they cause the contraction of skeletal muscle fibers.
What type of neurotransmitter primarily activates Nicotinic M receptors?
A) Norepinephrine
B) Epinephrine
C) Acetylcholine
D) Dopamine
Answer: C) Acetylcholine
Rationale: Nicotinic M receptors are activated by acetylcholine, which is released from motor neurons at the neuromuscular junction.
Which of the following best describes the role of Nicotinic M receptors in muscle physiology?
A) They inhibit muscle contraction to allow for relaxation.
B) They facilitate voluntary muscle contractions by responding to neural signals.
C) They primarily mediate involuntary muscle contractions.
D) They are involved in the release of hormones from the adrenal gland.
Answer: B) They facilitate voluntary muscle contractions by responding to neural signals.
Rationale: Nicotinic M receptors are essential for the contraction of skeletal muscle, enabling voluntary movements by responding to signals from motor neurons.
What are the adrenergic receptor subtypes?
Alpha 1
Alpha 2
Beta 1
Beta 2
Dopamine
Where are Alpha 1 receptors primarily located?
A) Heart, lungs, and brain
B) Eyes, blood vessels, male sex organs, prostate capsule, and bladder
C) Adrenal glands and pancreas
D) Skeletal muscle and liver
Answer: B) Eyes, blood vessels, male sex organs, prostate capsule, and bladder
Rationale: Alpha 1 receptors are primarily found in these tissues, where they play a key role in various physiological responses.
Which of the following is a function of Alpha 1 receptors?
A) Decrease heart rate
B) Dilation of blood vessels
C) Vasoconstriction and increased blood pressure
D) Relaxation of the bladder
Answer: C) Vasoconstriction and increased blood pressure
Rationale: Activation of Alpha 1 receptors causes vasoconstriction, which leads to increased blood pressure
What effect does the activation of Alpha 1 receptors have on the pupil?
A) Constriction of the pupil
B) Dilation of the pupil
C) No effect on the pupil
D) Blurred vision
Answer: B) Dilation of the pupil
Rationale: Activation of Alpha 1 receptors causes dilation of the pupil (mydriasis) as part of the body’s response to various stimuli.
Which physiological response is associated with Alpha 1 receptor activation in male sex organs?
A) Erection
B) Ejaculation
C) Inhibition of sexual function
D) Dilation of blood vessels
Answer: B) Ejaculation
Rationale: Activation of Alpha 1 receptors in male sex organs leads to ejaculation as part of the physiological sexual response.
