Practice Quiz For A&p II (Ans, Senses, And Endocrine)
ANS, Senses, and Endocrine
- 1.
Which of the following is not a parasympathetic ganglion?
- A.
Ciliary ganglion
- B.
Pterygopalatine ganglion
- C.
Submandibular ganglion
- D.
Otic ganglion
- E.
Celiac ganglion
Correct Answer
E. Celiac ganglionExplanation
The celiac ganglion is not a parasympathetic ganglion. Parasympathetic ganglia are located close to or within the target organs and are responsible for transmitting parasympathetic signals. The ciliary ganglion, pterygopalatine ganglion, submandibular ganglion, and otic ganglion are all examples of parasympathetic ganglia that are associated with specific cranial nerves and control various functions in the head and neck region. However, the celiac ganglion is part of the sympathetic nervous system and is involved in the regulation of abdominal organs.Rate this question:
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- 2.
Dual innervation refers to an organ receiving
- A.
Two nerves from the spinal cord
- B.
Both autonomic and somatomotor nerves
- C.
Both sympathetic and parasympathetic innervation
- D.
Nerves from both the brain and the spinal cord
- E.
Two nerves from the spinal cord and both autonomic and somatomotor nerves
Correct Answer
C. Both sympathetic and parasympathetic innervationExplanation
Dual innervation refers to an organ receiving both sympathetic and parasympathetic innervation. This means that the organ is innervated by both the sympathetic nervous system, which prepares the body for fight or flight responses, and the parasympathetic nervous system, which promotes rest and digestion. This dual innervation allows for fine control and regulation of the organ's functions, as the sympathetic and parasympathetic systems often have opposing effects on the organ.Rate this question:
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- 3.
During sympathetic activation, ________ occurs
- A.
Elevated heart rate
- B.
Elevated blood pressure
- C.
Sweating
- D.
Elevated blood glucose
- E.
All of the above
Correct Answer
E. All of the aboveExplanation
During sympathetic activation, the body's fight or flight response is triggered, leading to various physiological changes. These changes include an elevated heart rate, which helps pump more blood to the muscles and organs; elevated blood pressure, which helps facilitate blood flow and oxygen delivery to the body; sweating, which helps regulate body temperature; and elevated blood glucose levels, which provide an immediate energy source for the body. Therefore, all of the above options occur during sympathetic activation.Rate this question:
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- 4.
Preganglionic neurons of the autonomic nervous system are located in
- A.
The brain stem
- B.
The lateral gray horns of the spinal cord
- C.
The posterior gray horns of the spinal cord
- D.
Both the brain stem and the lateral gray horns of the spinal cord
- E.
The anterior gray horns of the spinal cord
Correct Answer
D. Both the brain stem and the lateral gray horns of the spinal cordExplanation
The correct answer is both the brain stem and the lateral gray horns of the spinal cord. Preganglionic neurons of the autonomic nervous system are located in both the brain stem and the lateral gray horns of the spinal cord. The brain stem contains preganglionic neurons that control autonomic functions in the head and neck, while the lateral gray horns of the spinal cord contain preganglionic neurons that control autonomic functions in the rest of the body. Therefore, both regions play a role in regulating the autonomic nervous system.Rate this question:
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- 5.
Postganglionic fibers that innervate targets in the body wall or thoracic cavity originate on neurons within
- A.
Intramural ganglia
- B.
Collateral ganglia
- C.
Sympathetic chain ganglia
- D.
Suprarenal ganglia
- E.
White rami
Correct Answer
C. Sympathetic chain gangliaExplanation
The postganglionic fibers that innervate targets in the body wall or thoracic cavity originate on neurons within the sympathetic chain ganglia. These ganglia are located on either side of the spinal cord and are part of the sympathetic division of the autonomic nervous system. The sympathetic chain ganglia receive preganglionic fibers from the spinal cord via the white rami, and then the postganglionic fibers extend from these ganglia to innervate their target organs or tissues. Therefore, the sympathetic chain ganglia are responsible for transmitting sympathetic signals to the body wall and thoracic cavity.Rate this question:
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- 6.
Which of the following would be an example of higher-level control of autonomic function?
- A.
Gagging on food that does not appeal to you
- B.
A violent coughing attack in response to an irritant
- C.
Increased heart rate when you see a person you fear
- D.
Dilation of the pupils when you enter a dark room
- E.
Increased salivation when you smell food that appeals to you
Correct Answer
C. Increased heart rate when you see a person you fearExplanation
Increased heart rate when you see a person you fear would be an example of higher-level control of autonomic function because it involves the activation of the sympathetic nervous system, which is responsible for the "fight or flight" response. This response is controlled by higher brain centers, such as the amygdala, which processes fear and triggers the release of stress hormones, leading to an increased heart rate. This response is not reflexive and can be influenced by conscious thoughts and emotions.Rate this question:
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- 7.
Nicotinic receptors
- A.
Respond to epinephrine
- B.
Respond to norepinephrine
- C.
Open chemically gated sodium ion channels
- D.
Open chemically gated calcium ion channels
Correct Answer
C. Open chemically gated sodium ion channelsExplanation
Nicotinic receptors are a type of receptor found in the nervous system that respond to the neurotransmitter acetylcholine. When acetylcholine binds to these receptors, they open chemically gated sodium ion channels, allowing sodium ions to enter the cell. This influx of sodium ions depolarizes the cell membrane, leading to the generation of an action potential. Therefore, the correct answer is that nicotinic receptors open chemically gated sodium ion channels.Rate this question:
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- 8.
The ________ division of the autonomic nervous system is known as the "rest and digest" division
- A.
Sympathetic
- B.
Parasympathetic
- C.
Thoracolumbar
- D.
Visceral
- E.
Somatomotor
Correct Answer
B. ParasympatheticExplanation
The parasympathetic division of the autonomic nervous system is known as the "rest and digest" division. It is responsible for conserving energy and promoting relaxation. This division helps in slowing down the heart rate, increasing digestion, and promoting activities that occur during rest and recovery. In contrast, the sympathetic division is responsible for the body's "fight or flight" response, which prepares the body for action and increases heart rate, blood pressure, and alertness.Rate this question:
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- 9.
Stimulation of α1 adrenergic receptors by norepinephrine results in
- A.
An increase in the amount of intracellular cAMP
- B.
A decrease in the amount of intracellular cAMP
- C.
Decreased membrane permeability to sodium ion
- D.
Release of calcium ions from intracellular stores
Correct Answer
D. Release of calcium ions from intracellular storesExplanation
Stimulation of α1 adrenergic receptors by norepinephrine results in the release of calcium ions from intracellular stores. This is because activation of α1 adrenergic receptors leads to the activation of phospholipase C, which in turn cleaves phosphatidylinositol 4,5-bisphosphate (PIP2) into inositol trisphosphate (IP3) and diacylglycerol (DAG). IP3 then binds to receptors on the endoplasmic reticulum, causing the release of calcium ions from intracellular stores. This increase in intracellular calcium ions can have various effects on cellular processes, such as muscle contraction or hormone secretion.Rate this question:
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- 10.
The celiac ganglion innervates the
- A.
Stomach
- B.
Liver
- C.
Pancreas
- D.
All of the above
Correct Answer
D. All of the aboveExplanation
The celiac ganglion is a cluster of nerves located in the abdomen. It is responsible for innervating various organs in the abdominal area, including the stomach, liver, and pancreas. Therefore, the correct answer is "all of the above" because the celiac ganglion innervates all three organs mentioned.Rate this question:
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- 11.
A visceral motor neuron whose cell body is within the CNS is called a(n) ________ neuron
- A.
Upper motor
- B.
Lower motor
- C.
Preganglionic
- D.
Postganglionic
- E.
Somatomotor
Correct Answer
C. PreganglionicExplanation
A visceral motor neuron whose cell body is within the CNS is called a preganglionic neuron. Preganglionic neurons are responsible for transmitting signals from the central nervous system to the autonomic ganglia, where they synapse with postganglionic neurons. These postganglionic neurons then innervate the target organs and carry out the autonomic functions of the body.Rate this question:
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- 12.
Mary accidentally ate poison mushrooms that contain muscarine. What symptoms would you expect to observe?
- A.
Diarrhea
- B.
Salivation
- C.
Very low heart rate
- D.
Sweating
- E.
All of the above
Correct Answer
E. All of the aboveExplanation
If Mary accidentally ate poison mushrooms containing muscarine, she would likely experience symptoms such as diarrhea, salivation, a very low heart rate, and sweating. Muscarine is a toxin that affects the parasympathetic nervous system, leading to increased activity in certain organs and glands. This can result in excessive salivation, increased intestinal motility causing diarrhea, a slowed heart rate, and sweating due to increased activity of sweat glands. Therefore, all of the above symptoms would be expected in this scenario.Rate this question:
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- 13.
Sympathetic nerves
- A.
Provoke feelings of sympathy
- B.
Allow us to relax, rest, and recover
- C.
Are bundles of postganglionic fibers that innervate organs within the thoracic cavity
- D.
Control swallowing
Correct Answer
C. Are bundles of postganglionic fibers that innervate organs within the thoracic cavityExplanation
Sympathetic nerves are bundles of postganglionic fibers that innervate organs within the thoracic cavity. This means that they are responsible for transmitting signals from the central nervous system to the organs in the chest region. These nerves play a crucial role in regulating various bodily functions such as heart rate, blood pressure, and breathing. They are part of the autonomic nervous system and work in conjunction with the parasympathetic nerves to maintain overall balance and homeostasis in the body.Rate this question:
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- 14.
Preganglionic fibers of parasympathetic neurons are present in all of the following cranial nerves, except N
- A.
III
- B.
VII
- C.
IX
- D.
X
- E.
I
Correct Answer
E. IExplanation
The explanation for the given correct answer is that cranial nerve I, also known as the olfactory nerve, is responsible for the sense of smell and does not have any parasympathetic function. On the other hand, cranial nerves III, VII, IX, and X all have preganglionic fibers of parasympathetic neurons that innervate various organs and glands in the head and neck region. Therefore, the correct answer is I.Rate this question:
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- 15.
A person is confronted by a dangerous dog. His heart begins to race and beat strongly, his pupils dilate, and his hairs stand up. These signs are the result of
- A.
Sympathetic activation
- B.
Increased levels of epinephrine in the blood
- C.
Increased activity of autonomic centers in the hypothalamus
- D.
All of the above
Correct Answer
D. All of the aboveExplanation
The person's physiological responses of increased heart rate, dilated pupils, and raised hairs are all signs of sympathetic activation. Sympathetic activation is the body's automatic response to a perceived threat or danger. This response is controlled by the autonomic centers in the hypothalamus, which increase activity to prepare the body for fight or flight. Additionally, this sympathetic activation triggers the release of epinephrine (also known as adrenaline) into the bloodstream, which further enhances the physiological responses. Therefore, all of the given options are correct explanations for the person's signs.Rate this question:
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- 16.
Preganglionic neurons of the sympathetic nervous system are located in the
- A.
Lateral gray horns of the cervical cord
- B.
Anterior gray horns of the cervical and thoracic spinal cord
- C.
Lateral gray horns of segments T1 to L2 of the spinal cord
- D.
Anterior gray horns of segments T1 to L2 of the spinal cord
- E.
Lateral gray horns of T1 to S2 of the spinal cord
Correct Answer
C. Lateral gray horns of segments T1 to L2 of the spinal cordExplanation
Preganglionic neurons of the sympathetic nervous system are located in the lateral gray horns of segments T1 to L2 of the spinal cord. This is because the sympathetic nervous system is responsible for the "fight or flight" response, which involves activating the body for action. The lateral gray horns of the spinal cord contain the cell bodies of preganglionic neurons that send signals to the sympathetic ganglia, which then relay the signals to the target organs. Segments T1 to L2 of the spinal cord correspond to the thoracic and upper lumbar regions, where the sympathetic ganglia are located.Rate this question:
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- 17.
The statement "its ganglia are usually near or within the end organ" is
- A.
True only for the parasympathetic nervous system
- B.
True only for the sympathetic nervous system
- C.
True for both the parasympathetic and sympathetic nervous systems
- D.
Not true for either the parasympathetic or sympathetic nervous systems
Correct Answer
A. True only for the parasympathetic nervous systemExplanation
The statement "its ganglia are usually near or within the end organ" is true only for the parasympathetic nervous system. This is because the parasympathetic nervous system has ganglia located near or within the target organs, allowing for a more localized and specific control of the organ's function. In contrast, the sympathetic nervous system has ganglia located closer to the spinal cord, which allows for a more widespread and generalized response throughout the body. Therefore, the statement is not true for the sympathetic nervous system.Rate this question:
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- 18.
Which of these provides preganglionic parasympathetic innervation to structures in the neck and in the thoracic and abdominopelvic cavities?
- A.
Vagus nerves
- B.
Sciatic nerves
- C.
Glossopharyngeal nerves
- D.
Pelvic nerves
- E.
Cervicothoracocabdominopelvic nerves
Correct Answer
A. Vagus nervesExplanation
The vagus nerves provide preganglionic parasympathetic innervation to structures in the neck and in the thoracic and abdominopelvic cavities.Rate this question:
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- 19.
Postganglionic sympathetic axons release the neurotransmitter ________ at their effector junctions
- A.
Acetylcholine
- B.
Nitric oxide
- C.
Norepinephrine
- D.
All of the above
Correct Answer
D. All of the aboveExplanation
Postganglionic sympathetic axons release the neurotransmitter acetylcholine at their effector junctions, as well as nitric oxide and norepinephrine. Acetylcholine is released at the synapses of the parasympathetic nervous system, but it also plays a role in the sympathetic system. Nitric oxide is a vasodilator that is released by sympathetic neurons to relax smooth muscle in blood vessels. Norepinephrine is the primary neurotransmitter released by sympathetic neurons, which activates adrenergic receptors to elicit a response in the target organ. Therefore, all of the above neurotransmitters are released by postganglionic sympathetic axons at their effector junctions.Rate this question:
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- 20.
Control of the diameter of the respiratory passages depends upon
- A.
Sympathetic stimulation only
- B.
Parasympathetic stimulation only
- C.
Somatomotor stimulation only
- D.
Both parasympathetic and sympathetic levels of stimulation
- E.
Sensory receptors sensitive to changes in lung ventilation
Correct Answer
D. Both parasympathetic and sympathetic levels of stimulationExplanation
The control of the diameter of the respiratory passages depends on both parasympathetic and sympathetic levels of stimulation. The parasympathetic nervous system causes bronchoconstriction, which narrows the airways, while the sympathetic nervous system causes bronchodilation, which widens the airways. Both systems work together to regulate the diameter of the respiratory passages and maintain proper airflow in the lungs.Rate this question:
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- 21.
In general, sympathetic preganglionic fibers are ________ and postganglionic fibers are ________.
- A.
Long; short
- B.
Short; long
Correct Answer
B. Short; longExplanation
Sympathetic preganglionic fibers are short because they originate from the spinal cord and synapse with ganglionic neurons in the sympathetic ganglia, which are located close to the spinal cord. On the other hand, sympathetic postganglionic fibers are long because they extend from the ganglia to innervate target organs or tissues located throughout the body. This allows for a widespread and coordinated response to stress or danger, which is characteristic of the sympathetic nervous system.Rate this question:
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- 22.
Parasympathetic stimulation
- A.
Increases heart rate.
- B.
Increases gastric motility.
- C.
Causes sweat glands to secrete.
- D.
Causes blood vessels in the skin to dilate.
- E.
Causes the pupils to dilate.
Correct Answer
B. Increases gastric motility.Explanation
Parasympathetic stimulation refers to the activation of the parasympathetic nervous system, which is responsible for rest and digestion. When the parasympathetic nervous system is stimulated, it increases gastric motility, meaning it promotes the movement and contraction of the muscles in the stomach and intestines, aiding in digestion and the absorption of nutrients. This response helps to break down food and move it through the digestive tract efficiently.Rate this question:
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- 23.
The statement "It controls the diameter of the pupil." is
- A.
True only for the parasympathetic nervous system.
- B.
True only for the sympathetic nervous system.
- C.
True for both the parasympathetic and sympathetic nervous systems.
- D.
Not true for either the parasympathetic or sympathetic nervous systems
Correct Answer
C. True for both the parasympathetic and sympathetic nervous systems.Explanation
The statement "It controls the diameter of the pupil" is true for both the parasympathetic and sympathetic nervous systems. The parasympathetic nervous system causes the pupil to constrict or become smaller, while the sympathetic nervous system causes the pupil to dilate or become larger. Therefore, both systems play a role in controlling the diameter of the pupil.Rate this question:
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- 24.
Preganglionic fibers leave the CNS and then synapse on
- A.
Visceral reflex responses.
- B.
Motor neurons.
- C.
Ganglionic neurons.
- D.
Sensory neuron neurons.
Correct Answer
C. Ganglionic neurons.Explanation
Preganglionic fibers leave the central nervous system (CNS) and then synapse on ganglionic neurons. Ganglionic neurons are located in peripheral ganglia and are responsible for relaying signals from the CNS to the target organs or tissues. This synapse allows for the transmission of information and coordination of visceral reflex responses, such as regulating heart rate or digestion. Motor neurons, on the other hand, are responsible for transmitting signals from the CNS to the muscles, while sensory neurons transmit signals from sensory organs to the CNS.Rate this question:
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- 25.
Clusters of ganglionic sympathetic neurons that innervate organs in the abdominopelvic region are called ________ ganglia.
- A.
Intramural
- B.
Collateral
- C.
Chain
- D.
Paravertebral
- E.
Suprarenal
Correct Answer
B. CollateralExplanation
Clusters of ganglionic sympathetic neurons that innervate organs in the abdominopelvic region are called collateral ganglia. Collateral ganglia are located outside the paravertebral chain and are situated close to the target organs they innervate. These ganglia receive preganglionic fibers from the sympathetic chain and provide postganglionic fibers to the organs in the abdominopelvic region.Rate this question:
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- 26.
A decrease in the autonomic tone of the smooth muscle in a blood vessel would result in
- A.
An increase in vessel diameter.
- B.
A decrease in vessel diameter.
- C.
Oscillation in vessel diameter.
- D.
An increase in blood flow through the vessel.
- E.
Both an increase in vessel diameter and an increase in blood flow through the vessel.
Correct Answer
E. Both an increase in vessel diameter and an increase in blood flow through the vessel.Explanation
A decrease in the autonomic tone of the smooth muscle in a blood vessel would result in an increase in vessel diameter. This is because the autonomic nervous system regulates the constriction and relaxation of smooth muscle in blood vessels. When the autonomic tone decreases, the smooth muscle relaxes, leading to vasodilation and an increase in vessel diameter. This, in turn, allows for an increase in blood flow through the vessel, as the larger diameter provides less resistance to the flow of blood. Therefore, both an increase in vessel diameter and an increase in blood flow through the vessel would occur.Rate this question:
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- 27.
Sympathetic innervation of the urinary bladder is by way of the
- A.
Celiac ganglion.
- B.
Superior mesenteric ganglion.
- C.
Inferior mesenteric ganglion.
- D.
Pudendal ganglion.
- E.
Pelvic ganglion.
Correct Answer
C. Inferior mesenteric ganglion.Explanation
The sympathetic innervation of the urinary bladder is provided by the inferior mesenteric ganglion. This ganglion is responsible for transmitting signals from the sympathetic nervous system to the bladder, helping to regulate its function. The other ganglia mentioned in the options are not specifically involved in the sympathetic innervation of the bladder.Rate this question:
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- 28.
The statement "Preganglionic axon terminals release acetylcholine." is
- A.
True only for the parasympathetic nervous system.
- B.
True only for the sympathetic nervous system.
- C.
True for both the parasympathetic and sympathetic nervous systems.
- D.
Not true for either the parasympathetic or sympathetic nervous systems.
Correct Answer
C. True for both the parasympathetic and sympathetic nervous systems.Explanation
The statement "Preganglionic axon terminals release acetylcholine" is true for both the parasympathetic and sympathetic nervous systems. In both systems, the preganglionic neurons release acetylcholine as their neurotransmitter. This acetylcholine then binds to nicotinic receptors on the postganglionic neurons, leading to the transmission of the nerve impulse to the target organ or tissue. This is a key characteristic of the autonomic nervous system, which is responsible for regulating involuntary bodily functions.Rate this question:
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- 29.
A pigment synthesized from vitamin A is
- A.
Retinal.
- B.
Opsin.
- C.
Rhodopsin.
- D.
Transducin.
Correct Answer
A. Retinal.Explanation
Retinal is a pigment synthesized from vitamin A. It is a key component of rhodopsin, a photosensitive pigment found in the rods of the retina. When light hits rhodopsin, it causes retinal to undergo a conformational change, triggering a cascade of events that ultimately leads to the generation of electrical signals in the retina and the perception of light. Opsin is a protein that combines with retinal to form rhodopsin, and transducin is a protein involved in the signal transduction pathway of rhodopsin.Rate this question:
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- 30.
Which of the following is not one of the six primary taste sensations?
- A.
Sweet
- B.
Peppery
- C.
Sour
- D.
Salty
- E.
Umami
Correct Answer
B. PepperyExplanation
The taste sensation "peppery" is not one of the six primary taste sensations. The six primary taste sensations are sweet, sour, salty, umami, bitter, and metallic. Peppery taste is often associated with the sensation of heat or spiciness, which is a different sensory experience than the primary taste sensations.Rate this question:
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- 31.
The quantity of neurotransmitter that is released by a hair cell
- A.
Responds to almost any mechanical stimulation of the hair cell.
- B.
Is sensitive to which way stereocilia are bent with respect to the kinocilium.
- C.
Determines if a sensory neuron will be excited.
- D.
All of the above
Correct Answer
D. All of the aboveExplanation
The correct answer is "all of the above." This means that the quantity of neurotransmitter released by a hair cell can respond to almost any mechanical stimulation of the hair cell, it is sensitive to the way stereocilia are bent with respect to the kinocilium, and it determines if a sensory neuron will be excited. In other words, all of these factors play a role in determining the quantity of neurotransmitter released by a hair cell.Rate this question:
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- 32.
The sensory receptors of the semicircular canals are located in the
- A.
Saccules.
- B.
Ampullae.
- C.
Perilymph.
- D.
Utricles.
- E.
Cupulae.
Correct Answer
B. Ampullae.Explanation
The sensory receptors of the semicircular canals are located in the ampullae. The ampullae are enlarged regions at the base of each semicircular canal, where the sensory hair cells are located. These hair cells detect the movement of fluid within the canals, which helps in maintaining balance and detecting changes in head position and movement. The ampullae contain the cupulae, which are gelatinous structures that deflect in response to fluid movement, stimulating the hair cells and sending signals to the brain about the body's orientation in space.Rate this question:
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- 33.
Which of the following is a component of the lamina propria of the olfactory organ?
- A.
Areolar tissue
- B.
Blood vessels
- C.
Nerves
- D.
Olfactory glands
- E.
All of the above
Correct Answer
E. All of the aboveExplanation
The lamina propria of the olfactory organ is a connective tissue layer that supports the olfactory epithelium. It contains various components such as areolar tissue, blood vessels, nerves, and olfactory glands. Areolar tissue provides structural support, blood vessels supply oxygen and nutrients, nerves transmit olfactory signals to the brain, and olfactory glands secrete mucus that helps in odor detection. Therefore, all of the options mentioned are components of the lamina propria of the olfactory organ.Rate this question:
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- 34.
The external ear ends at the
- A.
Vestibule.
- B.
Cochlea.
- C.
Ossicles.
- D.
Tympanic membrane.
- E.
Pinna.
Correct Answer
D. Tympanic membrane.Explanation
The external ear consists of the pinna, ear canal, and tympanic membrane. The pinna is the visible part of the ear, while the ear canal leads to the tympanic membrane, also known as the eardrum. The tympanic membrane marks the end of the external ear and separates it from the middle ear. It vibrates in response to sound waves and transmits them to the middle ear. Therefore, the correct answer is the tympanic membrane.Rate this question:
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- 35.
Taste buds are monitored by cranial nerves
- A.
IX, X, and XI.
- B.
VII, VIII, and IX.
- C.
VII, IX, and X.
- D.
V, VII, and IX.
Correct Answer
C. VII, IX, and X.Explanation
The taste buds, which are responsible for detecting different flavors, are monitored by cranial nerves VII, IX, and X. Cranial nerve VII, also known as the facial nerve, innervates the taste buds on the anterior two-thirds of the tongue. Cranial nerve IX, the glossopharyngeal nerve, innervates the taste buds on the posterior one-third of the tongue. Cranial nerve X, the vagus nerve, innervates the taste buds in the epiglottis and the back of the throat. Therefore, these three cranial nerves collectively monitor the taste buds throughout the tongue and throat.Rate this question:
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- 36.
All of the following are true of the fibrous tunic of the eye, except that it
- A.
Consists of the sclera, limbus, and cornea.
- B.
Provides mechanical support and some protection for the eye.
- C.
Produces aqueous humor.
- D.
Contributes substantial focusing power.
- E.
Is where extrinsic eye muscles insert.
Correct Answer
C. Produces aqueous humor.Explanation
The fibrous tunic of the eye consists of the sclera, limbus, and cornea, providing mechanical support and some protection for the eye. It also serves as the site where extrinsic eye muscles insert, allowing for eye movement and control. However, it does not produce aqueous humor. Aqueous humor is produced by the ciliary body, which is part of the vascular tunic of the eye.Rate this question:
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- 37.
The sensory neurons within the olfactory organ are stimulated by ________ in the air.
- A.
Pressure
- B.
Chemicals
- C.
Proteins
- D.
Water
- E.
Dust
Correct Answer
B. ChemicalsExplanation
The sensory neurons within the olfactory organ are stimulated by chemicals in the air. This is because the olfactory system is responsible for our sense of smell, and it detects and interprets different chemical compounds present in the air. These chemicals bind to receptors on the sensory neurons, triggering nerve impulses that are then transmitted to the brain, allowing us to perceive and distinguish various smells.Rate this question:
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- 38.
Pupillary muscle groups are controlled by the ANS. Parasympathetic activation causes pupillary ________, and sympathetic activation causes ________.
- A.
Dilation; constriction
- B.
Dilation; dilation
- C.
Constriction; dilation
- D.
Constriction; constriction
- E.
Vasoconstriction; vasoconstriction
Correct Answer
C. Constriction; dilationExplanation
The pupillary muscle groups are controlled by the autonomic nervous system (ANS). Parasympathetic activation causes pupillary constriction, which means the pupils become smaller. On the other hand, sympathetic activation causes pupillary dilation, which means the pupils become larger.Rate this question:
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- 39.
The first step in the process of photoreception is
- A.
The bleaching of rods.
- B.
The bleaching of cones.
- C.
Absorption of a photon by a visual pigment.
- D.
Inhibition of the sodium pumps.
- E.
Release of neurotransmitter.
Correct Answer
C. Absorption of a pHoton by a visual pigment.Explanation
The correct answer is absorption of a photon by a visual pigment. Photoreception is the process by which light is detected and converted into electrical signals in the retina of the eye. This process begins with the absorption of a photon, which is a particle of light, by a visual pigment. This absorption causes a chemical change in the pigment, triggering a series of events that ultimately lead to the generation of an electrical signal that can be transmitted to the brain for further processing and interpretation.Rate this question:
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- 40.
Movement of the endolymph in the semicircular canals
- A.
Produces a rushing sound.
- B.
Allows us to hear low tones.
- C.
Signals rotational movements.
- D.
Signals body position with respect to gravity.
- E.
Signals linear acceleration.
Correct Answer
C. Signals rotational movements.Explanation
The movement of the endolymph in the semicircular canals is responsible for signaling rotational movements. The semicircular canals are fluid-filled structures in the inner ear that detect changes in head rotation. When the head moves, the endolymph inside the canals also moves, stimulating hair cells that send signals to the brain. This allows us to sense and perceive rotational movements, such as turning our head or spinning around. Therefore, the correct answer is that the movement of the endolymph in the semicircular canals signals rotational movements.Rate this question:
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- 41.
Which of the following descriptions best matches the term aqueous humor?
- A.
Gelatinous fluid that fills posterior chamber
- B.
Secreted in bright light
- C.
Constantly produced and recycled
- D.
Converts to vitreous humor with age
Correct Answer
C. Constantly produced and recycledExplanation
The term "aqueous humor" refers to a gelatinous fluid that is constantly produced and recycled. This fluid fills the posterior chamber of the eye and helps maintain its shape and nourish the surrounding tissues. It also plays a role in regulating intraocular pressure.Rate this question:
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- 42.
In the retina, the correct sequence of neural wiring is
- A.
Rod - bipolar cell — ganglion cell - thalamus
- B.
Cone - bipolar cell — pigmented cell - inferior colliculus
- C.
Cone - bipolar cell - horizontal cell — pigmented cell
- D.
Rod - bipolar cell — pigmented cell - thalamus
- E.
Rod - bipolar cell - amacrine cell — pigmented cell
Correct Answer
A. Rod - bipolar cell — ganglion cell - thalamusExplanation
The correct sequence of neural wiring in the retina starts with the rod cells, which transmit signals to bipolar cells. The bipolar cells then relay the signals to ganglion cells, which send the information to the brain via the optic nerve. From the optic nerve, the signals are sent to the thalamus, which acts as a relay station for sensory information before it reaches the visual cortex for processing.Rate this question:
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- 43.
The ciliary muscle contracts to
- A.
Control the amount of light reaching the retina.
- B.
Adjust the shape of the lens for distant vision.
- C.
Adjust the shape of the lens for close vision.
- D.
Control the production of aqueous humor.
- E.
Adjust the shape of the cornea and vitreous.
Correct Answer
C. Adjust the shape of the lens for close vision.Explanation
The ciliary muscle contracts to adjust the shape of the lens for close vision. When the ciliary muscle contracts, it causes the lens to become thicker and more rounded, allowing the eye to focus on nearby objects. This process is known as accommodation and is necessary for clear vision at close distances.Rate this question:
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- 44.
Autonomic tone is an important aspect of ANS function because it
- A.
Allows ANS neurons to be silent under normal conditions.
- B.
Allows ANS neurons to increase activity on demand but not decrease their activity.
- C.
Allows ANS neurons to decrease their activity on demand but not increase their activity.
- D.
Allows ANS neurons to increase or decrease their activity, providing a range of control options.
Correct Answer
D. Allows ANS neurons to increase or decrease their activity, providing a range of control options.Explanation
Autonomic tone is important for ANS function because it allows ANS neurons to increase or decrease their activity, providing a range of control options. This means that the ANS can respond to changing conditions and maintain homeostasis by either increasing or decreasing its activity as needed. It allows for flexibility and adaptability in regulating various bodily functions such as heart rate, blood pressure, digestion, and respiratory rate.Rate this question:
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- 45.
Muscarinic receptors
- A.
Are normally activated by acetylcholine.
- B.
Are found mostly in autonomic ganglia.
- C.
Always produce an excitatory response.
- D.
Control sodium channels in the affected membrane.
- E.
Are blocked by norepinephrine.
Correct Answer
A. Are normally activated by acetylcholine.Explanation
Muscarinic receptors are a type of receptor that are typically activated by the neurotransmitter acetylcholine. These receptors are found in various parts of the body, including smooth muscle, cardiac muscle, and certain glands. Activation of muscarinic receptors can lead to a variety of responses, including both excitatory and inhibitory effects depending on the specific tissue and receptor subtype involved. Norepinephrine, on the other hand, typically acts on adrenergic receptors and does not directly block muscarinic receptors.Rate this question:
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- 46.
Which of the following statements about adrenergic receptors is true?
- A.
They are proteins in the plasma membrane.
- B.
Epinephrine activates both alpha and beta types.
- C.
Norepinephrine activates mainly the alpha type.
- D.
All of the above
Correct Answer
D. All of the aboveExplanation
The correct answer is "all of the above." This means that all of the statements given about adrenergic receptors are true. Adrenergic receptors are indeed proteins located in the plasma membrane. Additionally, both epinephrine and norepinephrine can activate alpha and beta types of adrenergic receptors, although norepinephrine mainly activates the alpha type.Rate this question:
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- 47.
Parasympathetic functions include all of the following, except
- A.
Decrease in the rate of cardiac contraction.
- B.
Constriction of the pupils
- C.
Dilation of the airways.
- D.
Stimulation of urination.
- E.
Stimulation of defecation.
Correct Answer
C. Dilation of the airways.Explanation
Parasympathetic functions are responsible for conserving energy and promoting rest and digest activities in the body. These functions include decreasing the rate of cardiac contraction, constriction of the pupils, stimulation of urination, and stimulation of defecation. However, dilation of the airways is not a parasympathetic function. Instead, it is a sympathetic function, which is responsible for the fight or flight response and increases the diameter of the airways to facilitate increased airflow during times of stress or exercise.Rate this question:
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- 48.
Which of the following statements concerning the parasympathetic division of the autonomic nervous system is false?
- A.
Preganglionic neurons are located in the brainstem and sacral region of the spinal cord.
- B.
Ganglionic neurons are located in ganglia within or near to effectors.
- C.
Preganglionic fibers are relatively short and postganglionic fibers are relatively long.
- D.
The actions of the parasympathetic division are more localized than those of the sympathetic division.
- E.
The ganglionic neurons always release acetylcholine.
Correct Answer
C. Preganglionic fibers are relatively short and postganglionic fibers are relatively long.Explanation
The correct answer is that the statement "Preganglionic fibers are relatively short and postganglionic fibers are relatively long" is false. In the parasympathetic division of the autonomic nervous system, the preganglionic fibers are relatively long, while the postganglionic fibers are relatively short. This is the opposite of what is stated in the false statement.Rate this question:
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- 49.
All of the following are true of olfactory pathways, except
- A.
They project first to the mamillary bodies and then to the thalamus.
- B.
The first synapse is in the olfactory bulb.
- C.
Information flows to the olfactory cortex, hypothalamus, and limbic system.
- D.
They reach the forebrain without first synapsing in the thalamus.
- E.
They exhibit a considerable amount of convergence.
Correct Answer
A. They project first to the mamillary bodies and then to the thalamus.Explanation
Olfactory pathways do not project first to the mamillary bodies and then to the thalamus. Instead, they reach the forebrain without first synapsing in the thalamus. The olfactory bulb is the site of the first synapse in the olfactory pathways. Information then flows to the olfactory cortex, hypothalamus, and limbic system. Olfactory pathways also exhibit a considerable amount of convergence, meaning that multiple olfactory receptor neurons can synapse onto a single mitral cell in the olfactory bulb.Rate this question:
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- 50.
Before an olfactory receptor can detect an odorant, it has to
- A.
Contact a specialized olfactory cell.
- B.
Bind to receptors in olfactory cilia.
- C.
Gate open ion channels.
- D.
Respond to applied pressure.
- E.
Be transported to the olfactory bulbs.
Correct Answer
B. Bind to receptors in olfactory cilia.Explanation
Olfactory receptors are located in specialized olfactory cilia, which are tiny hair-like structures in the nose. These receptors are responsible for detecting odorants. When an odorant molecule binds to the receptors in the olfactory cilia, it triggers a series of biochemical reactions that generate electrical signals, which are then transmitted to the brain for interpretation. Therefore, for an olfactory receptor to detect an odorant, it must first bind to receptors in the olfactory cilia.Rate this question:
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Mar 21, 2023Quiz Edited by
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Sep 07, 2012Quiz Created by
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