400 item
1. The impulse-conducting cells of the nervous system are called?
Answer: Cranial Nerve V
2. What is the blood-brain barrier?
Answer: C. It’s a semi-permeable membrane that permits small molecules like oxygen and carbon dioxide to diffuse across to the brain but blocks larger molecules.
3. Which neurons detect sensations such as touch or heat and then relay information about the stimuli to the central nervous system?
Answer: C. Afferent neurons
4. The sympathetic division of the autonomic nervous system
Answer: B. decreases heart rate and digestive activity.
5. When the action potential begins, Na+ gates open, allowing Na to cross the membrane. The charge difference across the axon membrane changes to
Answer: B. positive outside and negative inside.
6. Transmission of a nerve impulse across a synapse is accomplished by the
Answer: C. release of a neurotransmitter by an axon.
7. Which statement regarding spinal nerves is true?
Answer: A. Spinal nerves are mixed nerves, containing both sensory and motor fibers, making it capable of transmitting impulses in two directions.
8. Which key nerve is part of the sacral plexus?
Answer: C. Sciatic nerve
9. Which portion of the brain contains centers responsible for such vital functions as heart rate, breathing, and blood pressure?
Answer: B. Medulla oblongata
10. Which of the following is a characteristic of the somatic nervous system?
Answer: D. It operates under voluntary control.
11. The impulse-conducting cells of the nervous system are called:
Answer: B. Neurons
12. What is the blood-brain barrier?
Answer: C. It’s a semi-permeable membrane that permits small molecules like oxygen and carbon dioxide to diffuse across to the brain but blocks larger molecules.
13. Which neurons detect sensations such as touch or heat and then relay information about the stimuli to the central nervous system?
Answer: C. Afferent neurons
14. A nerve cell in which phase cannot respond to a new stimulus?
Answer: D. Refractory period
15. Which statement regarding spinal nerves is true?
Answer: A. Spinal nerves are mixed nerves, containing both sensory and motor fibers, making it capable of transmitting impulses in two directions.
16. Which key nerve is part of the sacral plexus?
Answer: C. Sciatic nerve
17. Which statement about cerebrospinal fluid (CSF) is true?
Answer: C. CSF furnishes the brain with glucose and protein.
18. Which portion of the brain contains centers responsible for such vital functions as heart rate, breathing, and blood pressure?
Answer: B. Medulla oblongata
19. Which brain structure influences nearly every organ and exerts control over the autonomic nervous system and pituitary gland?
Answer: D. Hypothalamus
20. An injury to which part of the brain may result in a severe personality disorder and cause socially inappropriate behavior?
Answer: A. Frontal lobe
21. Which area of the brain receives impulses of heat, cold, and touch from receptors all over the body and is, therefore, known as the primary somatic sensory area?
Answer: D. Postcentral gyrus
22. Which cranial nerve supplies most of the organs in the thoracic and abdominal cavities as well as those in the head and neck?
Answer: C. Vagus
23. Brain swelling from a head injury can compress this nerve and interfere with the ability of the pupils to react to light.
Answer: A. Oculomotor
24. Which of the following is a characteristic of the somatic nervous system?
Answer: D. It operates under voluntary control.
25. Which of the following is one of the actions of the parasympathetic division of the autonomic nervous system?
Answer: B. Constricts bronchial tubes
26. Which of the following statements correctly describes cholinergic fibers?
Answer: C. Cholinergic fibers secrete acetylcholine.
27. The effect produced by a neurotransmitter (such as whether it constricts or dilates blood vessels) is ultimately determined by:
Answer: C. the type of receptor.
28. The blood-brain barrier is effective against the passage of:
Answer: B) metabolic waste such as urea
29. The sympathetic and parasympathetic nervous systems are subdivisions of the:
Answer: A) autonomic nervous system
30. An action potential:
Answer: D) is essential for nerve impulse propagation
31. The effects of the sympathetic nervous system are essentially opposite of the:
Answer: B) parasympathetic nervous system
32. Claudine has a brain injury; she knows what she wants to say but can’t vocalize the words. The part of her brain that deals with the ability to speak is the:
Answer: B) Broca’s area
33. Which of these cells are not a type of neuroglia found in the CNS:
Answer: A) Schwann cells
34. Lobe that contains the primary motor area that enables voluntary control of skeletal muscle movements:
Answer: A) frontal lobe
35. The elevated ridges of tissue on the surface of the cerebral hemispheres are known as while the shallow grooves are termed:
Answer: D) gyri; sulci
36. An action potential is caused by an influx of these ions into the cell:
Answer: C) sodium
37. The function of the olfactory nerve concerns:
Answer: A) smell
38. The gap between two communicating neurons is termed:
Answer: B) synaptic cleft
39. Afferent nerves are called, and motor nerves are called:
Answer: B) sensory nerves; efferent nerves
40. The substance that is released at axonal endings to propagate a nervous impulse is called:
Answer: D) a neurotransmitter
41. Family members would like to bring in birthday cake for a client with nerve damage. What cranial nerve needs to be functioning so the client can chew?
Answer: B) Cranial nerve V
42. The nurse is caring for the client following a cerebral vascular accident. Which portion of the brain is responsible for taste, smell, and hearing?
Answer: C) Temporal
43. The assessment that ensures the ER nurse that a patient’s spinal cord injury is below C4 is:
Answer: C) Unlabored respiration
44. Bell’s palsy is a disorder of cranial nerve VII. What are the clinical manifestations of the disorder?
Answer: B) Facial paralysis
45. The nurse is assessing a patient with a head injury due to a motor vehicle accident who is experiencing temporary blindness in the left eye would be correct in documenting this abnormal finding as corresponding to which of the following cerebral lobes?
Answer: B) Occipital
46. A nurse completing a neurological assessment on a patient with Meniere’s disease is assessing cranial nerve VIII. The nurse would be correct in identifying the function of this nerve as which of the following?
Answer: D) Hearing and equilibrium
47. The nurse is assessing a patient who exhibits an uncoordinated gait knows that which of the following brain structures affects balance and coordination?
Answer: A) Cerebellum
48. A nurse is caring for a patient with altered level of consciousness is preparing to test cranial nerve. The nurse would complete which of the following assessment techniques to elicit a response from cranial nerve VII?
Answer: C) Observe for symmetry of facial movements, such as smile
49. A patient with a C3 spinal cord injury is exhibiting extreme temperature elevations due to his injury. The nurse knows that the area of the brain that regulates body temperature is which of the following?
Answer: C) Hypothalamus
50. The meninges provide protection, support, and nourishment to the brain and spinal cord. Which of the following terms is used to describe the fibrous connective tissue that hugs the brain closely and extends into every fold of the brain’s surface?
Answer: D) Pia mater
51. The patient is postoperative following a radial neck dissection. The physician who asks the patient to stick out his tongue and move it back and forth is assessing for damage to which of the following?
Answer: A) Hypoglossal nerve
52. A patient’s parasympathetic system has been stimulated. Which of the following is an effect of parasympathetic stimulation?
Answer: A) Constricted pupils
53. A patient who is extremely upset after a confrontation with a family member is having a “fight or flight response.” What effect will this have on the sympathetic nervous system?
Answer: C) Increased secretion of sweat
54. It is essential for an elderly patient who lives alone and has atrophy of his olfactory organs to have which of the following installed in the home?
Answer: D) A smoke detector
55. To assess a patient’s cranial nerve function, the nurse should assess:
Answer: D) Gag reflex
56. What is the nurse likely to find when assessing a patient who has suffered a LEFT stroke?
Answer: C) Right visual field defects
57. The nurse teaching a patient with trigeminal neuralgia about the factors that precipitate an attack would be correct in teaching him to avoid:
Answer: A) Washing his face
58. The peripheral nervous system includes the:
Answer: A) Somatic nervous system
59. The part of the nervous system that controls smooth muscle, cardiac muscle, and glands is the:
Answer: B) Autonomic nervous system
60. Concerning concentration differences across the plasma membrane, there are:
Answer: D) More K+ inside the cell than outside and more Na+ outside the cell than inside
61. Which of these is a correct count of the spinal nerves?
Answer: B) 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal
62. Important centers for heart rate, blood pressure, respiration, swallowing, coughing, and vomiting are located in the:
Answer: B) Medulla oblongata
63. In which of these parts of the brain does decussation of descending nerve tracts involved in the conscious control of skeletal muscles occur?
Answer: E) Medulla oblongata
64. Important respiratory centers are located in the:
Answer: C) Pons and medulla oblongata
65. Which of these cerebral lobes is important in voluntary motor function, motivation, aggression, sense of smell, and mood?
Answer: A) Frontal
66. The most superficial of the meninges is a thick, tough membrane called the:
Answer: B) Dura mater
67. Cerebrospinal fluid is produced by the [blank], circulates through the ventricles, and enters the subarachnoid space. The cerebrospinal fluid leaves the subarachnoid space through the [blank].
Answer: A) Choroid plexuses, arachnoid granulations
68. The cranial nerve responsible for focusing the eye (innervates the ciliary muscle of the eye) is the:
Answer: B) Oculomotor (III)
69. The cranial nerve involved in feeling a toothache is the:
Answer: B) Trigeminal (V)
70. From this list of cranial nerves: 1. olfactory (I), 2. optic (II), 3. oculomotor (III), 4. abducens (VI), 5. vestibulocochlear (VIII)
Answer: C) 1, 2, 5
71. From this list of cranial nerves: 1. trigeminal (V), 2. facial (VII), 3. glossopharyngeal (IX), 4. vagus (X), 5. hypoglossal (XII)
Answer: A) 1, 2, 3
72. Which of these activities is mostly associated with the left cerebral hemisphere in most people?
Answer: B) Mathematics and speech
73. The limbic system is involved in the control of:
Answer: D) Emotion, mood, and sensations of pain or pleasure
74. Neurons have cytoplasmic extensions that connect one neuron to another neuron. Given these structures: 1. axon, 2. dendrite, 3. dendritic spine, 4. presynaptic terminal. Choose the arrangement that lists the structures in the order they are found between two neurons.
Answer: D) 4, 1, 3, 2
75. Gray matter contains primarily:
Answer: B) Neuron cell bodies
76. Neurotransmitter substances are stored in vesicles that are located in specialized portions of the:
Answer: B) Axon
77. Given these components of a reflex arc: 1. effector organ, 2. interneuron, 3. motor neuron, 4. sensory neuron, 5. sensory receptor. Choose the correct order an action potential follows after a sensory receptor is stimulated.
Answer: B) 5, 4, 2, 3, 1
78. Damage to the dorsal ramus of a spinal nerve results in:
Answer: C) Both A and B (loss of sensation and loss of motor function)
79. A person with a spinal cord injury is suffering from paresis (partial paralysis) in the right lower limb. Which of these pathways is probably involved?
Answer: B) Right lateral corticospinal tract
80. Given these areas of the cerebral cortex: 1. Broca’s area, 2. premotor area, 3. primary motor cortex, 4. Wernicke’s area. If a person hears and understands a word and then says the word out loud, in what order are the areas used?
Answer: B) 1, 4, 3, 2
81. Which of these is not one of the basic tastes?
Answer: A) Spicy
82. Given these structures: 1. lens, 2. aqueous humor, 3. vitreous humor, 4. cornea. Choose the arrangement that lists the structures in the order that light entering the eye encounters them.
Answer: D) 4, 2, 1, 3
83. Sounds are detected by [blank] receptors.
Answer: C) Mechano
84. Which of the following is not likely to cause a headache?
Answer: C) A full stomach
85. An analgesic is a drug which usually [blank] pain impulses.
Answer: B) Decreases
86. Which area allows one to perceive the aroma of a pizza?
Answer: C) Olfactory cortex
87. Which sense is most likely to adapt rapidly?
Answer: B) Smell
88. Which of the following could be detected on the back of the tongue?
Answer: D) Bitter
89. The purpose of the auricle is to [blank] sound waves.
Answer: C) Act as a collector of
90. The auditory tube acts to equalize pressure between the middle ear and [blank].
Answer: A) Throat
91. The term labyrinth refers to the appearance of the [blank].
Answer: B) Inner ear
92. The cells that convert vibrations into neurological impulses are the [blank] cells.
Answer: A) Hair
93. The process of adjusting vision from a near to a distant object is called [blank].
Answer: B) Accommodation
94. An increase in aqueous fluid pressure is a symptom of [blank].
Answer: C) Glaucoma
95. The point of sharpest retinal vision is called the [blank].
Answer: A) Fovea centralis
96. Which of these photoreceptor cells is not correctly matched with its function?
Answer: B) Rods—visual acuity
97. A person with an abnormally long eyeball (anterior to posterior) is [blank] and uses a [blank] to correct his or her vision.
Answer: A) Nearsighted, concave lens
98. An increase in the loudness of sound occurs as a result of an increase in the [blank] of the sound wave.
Answer: B) Amplitude
99. Tears:
Answer: E) Contain water, salts, mucus, and lysozyme
100. In the retina, there are cones that are most sensitive to a particular color. Given this list of colors: 1. red, 2. yellow, 3. green, 4. blue.
Answer: E) 1, 2, 3, 4
101. Glands that secrete their product into the interstitial fluid, which flows into the blood are:
Answer: A) Endocrine glands
102. Cells that respond to a hormone are:
Answer: A) Target cells
103. The following is ‘not’ a steroid hormone:
Answer: B) Epinephrine
104. The endocrine system uses to control and send messages:
Answer: B) Hormones
105. The hormone that stimulates ovulation is:
Answer: B) Lutenising hormone (LH)
106. The gland that does the most to regulate and maintain the function of other glands is the:
Answer: B) Pituitary
107. Which of the following is ‘not’ a pituitary hormone:
Answer: A) Progesterone
108. Oxytocin stimulates contraction of the uterine smooth muscle during:
Answer: A) Childbirth
109. The endocrine gland that initiates antibody development by producing thymosin is:
Answer: C) Thymus
110. Which of the following is a response to stress?
Answer: D) Increase the respiratory rate
111. The testes are responsible for the production of:
Answer: C) Sperm and testosterone
112. The mammary glands are situated:
Answer: A) In the breast
113. The salivary glands produce:
Answer: C) Saliva
114. Insulin is produced in the:
Answer: D) Pancreas
115. The hypothalamus links the endocrine system to the:
Answer: A) Nervous system
116. The following is a condition of the endocrine system:
Answer: B) Addison’s Disease
117. Diabetes occurs when a person doesn’t produce enough insulin:
Answer: A) Pancreas
118. The ovaries are located:
Answer: B) On the left and right side of the pelvic cavity
119. The pancreatic endocrine glands are clusters of cells called the:
Answer: D) Islets of Langerhans
120. The gland is a small oval gland thought to play a role in regulating the body’s biological clock:
Answer: A) Pineal
121. Accessory glands that produce an oily secretion are the
Answer: C) tarsal glands
122. The portion of the fibrous layer that is white and opaque is the
Answer: D) sclera
123. Which sequence best describes a normal route for the flow of tears from the eyes into the nasal cavity?
Answer: A) lacrimal canaliculi, lacrimal sacs, nasolacrimal ducts
124. Activation of the sympathetic nervous system causes
Answer: B) contraction of the dilator pupillae muscles
125. Damage to the medial recti muscles would probably affect
Answer: C) convergence
126. The phenomenon of dark adaptation is best explained by the fact that
Answer: C) rods exposed to intense light need time to generate rhodopsin
127. Blockage of the scleral venous sinus might result in
Answer: B) glaucoma
128. Nearsightedness is more properly called
Answer: A) myopia
129. Of the neurons in the retina, the axons of which of these form the optic nerve?
Answer: B) ganglion cells
130. Which sequence of reactions occurs when a person looks at a distant object?
Answer: B) pupils dilate, ciliary zonule becomes taut, lenses become less convex
131. During embryonic development, the lens of the eye forms
Answer: B) from the surface ectoderm overlying the optic cup
132. The blind spot of the eye is
Answer: D) where the optic nerve leaves the eye
133. Olfactory tract damage would probably affect your ability to
Answer: D) smell
134. Sensory impulses transmitted over the facial, glossopharyngeal, and vagus nerves are involved in the sensation of
Answer: A) taste
135. Taste buds are found on the
Answer: D) all of these
136. Gustatory epithelial cells are stimulated by
Answer: C) substances in solution
137. Cells in the olfactory bulb that act as local “integrators” of olfactory inputs are the
Answer: B) amacrine granule cells
138. Olfactory nerve filaments are found
Answer: B) passing through the cribriform plate of the ethmoid bone
139. Conduction of sound from the middle ear to the internal ear occurs via vibration of the
Answer: B) stapes in the oval window
140. The transmission of sound vibrations through the internal ear occurs chiefly through
Answer: C) fluid
141. Which of the following statements does not correctly describe the spiral organ?
Answer: D) the more numerous outer hair cells are largely responsible for our perception of sound
142. Pitch is to frequency of sound as loudness is to
Answer: B) intensity
143. The structure that allows pressure in the middle ear to be equalized with atmospheric pressure is the
Answer: B) pharyngotympanic tube
144. Which of the following is important in maintaining the balance of the body?
Answer: E) all of these
145. Equilibrium receptors that report the position of the head in space relative to the pull of gravity are
Answer: B) maculae
146. Which of the following is not a possible cause of conduction deafness?
Answer: C) cochlear nerve degeneration
147. Which of the following are intrinsic eye muscles?
Answer: C) smooth muscles of the iris and ciliary body
148. Which lies closest to the exact posterior pole of the eye?
Answer: B) optic disc
149. Otoliths (ear stones) are
Answer: C) important in equilibrium
150. The transmission of sound waves through the tympanic cavity of the middle ear occurs through:
Answer: A) air
151. The two sac-like structures of the inner ear called the utricle and saccule:
Answer: B) are part of the membranous labyrinth within the vestibule
152. Which of the following is not one of the auditory ossicles?
Answer: C) stapedius
153. Middle ear infection may follow a throat infection because:
Answer: B) the pharyngeal (throat) mucosa is continuous with the mucosa of the middle ear
154. The waxy material in the external auditory canal (meatus) is the product of
Answer: D) ceruminous glands
155. The auricle or pinna of the outer ear contains:
Answer: B) elastic cartilage
156. In the physiology of hearing, which action is it that generates an action potential that causes release of a neurotransmitter substance?
Answer: C) movement of the spiral organ hair cells against the rectorial membrane
157. Otoliths (crystals of CaCO3) are located in the:
Answer: D) answers A and C
158. Aqueous humor:
Answer: E) all of the above
159. A lesion that destroyed the left optic tract of a boy affected his eye by eliminating action potentials (=impulses) that would normally have been generated in response to light in the:
Answer: E) answers B and C
160. Which of the following is not part of the vascular layer or uvea?
Answer: A) cornea
161. During embryonic development, the lens of the eye forms:
Answer: E) none of the above
162. Obstruction of the scleral venous sinus (=canal of Schlemm) interferes with the:
Answer: D) drainage of aqueous humor
163. Which of the following cannot be seen as one looks into the eye through an ophthalmoscope?
Answer: B) optic chiasma
164. A person with an abnormally short eyeball (anterior to posterior) would be and would wear lenses to correct their vision.
Answer: D) farsighted convex
165. The perception of color comes from all the following except:
Answer: B) yellow cones
166. The visible outer white surface of the eye is covered by a distinctive epithelium continuous with the inner lining of the eyelids. This epithelium is called the:
Answer: D) conjunctiva
167. What structure regulates the amount of light passing to the visual receptors of the eye?
Answer: B) pupil
168. Vision is most acute when light rays are brought to focus on the:
Answer: A) fovea centralis
169. Night blindness can be treated with:
Answer: D) none of the preceding
170. Loss of the sense of taste on the posterior 1/3 of the tongue might be due to injury to:
Answer: C) cranial nerve IX
171. Receptors that respond quickly to a stimulus but then adapt (sensory adaptation) and decrease their firing rate are called:
Answer: A) phasic receptors
172. Which describes the effect of the sympathetic system on the eye pupil and the muscles involved in the action?
Answer: C) dilates / radial muscles
173. How many different modalities are associated with olfaction?
Answer: E) hundreds or even thousands
174. The bone that contains the osseous labyrinth is the:
Answer: A) temporal bone
175. During embryonic development the tympanic cavity develops from the:
Answer: E) 1st pharyngeal pouch
176. The position of joints and the state of muscular contraction is monitored by:
Answer: E) proprioceptors
177. The organs of taste are called:
Answer: D) taste buds
178. A cut on the finger would activate which receptors?
Answer: B) nociceptors
179. Receptors for general senses provide information for all the following except:
Answer: D) sight
180. Receptors for light touch are called and they are located in the
Answer: D) Meissner's corpuscles / dermis
181. The oval window is located at the base of the:
A. scala vestibule
182. Sympathetic stimulation of the iris causes:
C. Pupillary dilation
183. Cone cells are photoreceptors that respond to:
E. Colored light
184. The region where the lens focuses the image onto the retina is the:
B. Fovea
185. The fluid that fills the posterior chamber of the eye is the:
C. Aqueous humor
186. The major light-absorbing pigment in retinal photoreceptors is:
A. Rhodopsin
187. Sounds are detected by - receptors.
C. mechano
188. The are the actual areas that respond to chemical stimulations for the sense of smell.
B. olfactory mucous membrane cells
189. The olfactory receptor cells are examples of neurons.
D. bipolar
190. Which area allows one to perceive the aroma of a pizza?
C. olfactory cortex
191. Which sense is most likely to adapt rapidly?
B. smell
192. A person aged 21 will probably lose of their smell at 22.
A. none
193. The visible elevations on the tongue that contain the receptors for taste are the:
C. papillae
194. Which of the following could be detected on the back of the tongue?
D. bitter
195. Which of these does not belong with the rest?
C. alkaline
196. The nerves that convey taste sensations, are the following except which one?
B. VIII
197. The gustatory cortex is located within the lobe.
A. temporal
198. Which of these does not belong with the others?
D. malleus
199. The purpose of the auricle is to sound waves.
C. act as a collector of
200. The first structure to vibrate in response to sounds is:
D. tympanic membrane
201. The following belong together except which one?
D. cochlear duct
202. The purpose of the ossicles is to the incoming vibrations.
B. increase the force of
203. The stapes sends its vibrations to the:
C. oval window
204. Which of these does not belong with the others?
C. increase sound
205. The auditory tube acts to equalize pressure between the middle ear and:
A. throat
206. The term labyrinth refers to the appearance of the:
B. inner ear
207. The membranous labyrinth contains fluid.
C. endolymph
208. The portion of the inner ear that detects sounds is the:
D. cochlea
209. Reissner's membrane separates the cochlear duct from the:
B. scala vestibuli
210. Vibrations from the reach the scala vestibuli first.
C. oval window
211. The cells that convert vibrations into neurological impulses are the:
A. hair cells
212. The connection between the cochlear hair cells and the VIII cranial nerve are made by:
B. release of neurotransmitter
213. The intensity of sounds is measured in units of:
D. dB
214. The auditory perception center is located within the:
C. temporal lobe
215. Which type of deafness can be treated by a cochlear implant?
C. sensorineural
216. The following belong together except which one?
C. static equilibrium
217. The maculae can be found in the:
B. saccule
218. Stimulation of the crista ampullaris results in:
C. feeling of motion
218. The term for eyelid is:
D. palpebra
219. Tears drain into the openings of the:
A. puncta
220. Movement of the eyeball is effected by muscles innervated mainly by the nerve.
C. oculomotor
221. The outer covering of the eye is called the:
C. sclera
222. The suspensory ligaments attach to the:
A. lens
223. The process of adjusting vision from a near to a distant object is called:
B. accommodation
224. An increase in aqueous fluid pressure is a symptom of:
C. glaucoma
225. Which of the following is the first to come into contact with light?
C. cones
226. The point of sharpest retinal vision is called the:
A. fovea centralis
227. Which of the following is decomposed under light?
C. rhodopsin
228. A sensory receptor capable of detecting changes in hydrogen ion concentration is more accurately described as:
D. chemoreceptor
229. Which of these statements about the sense of smell is not true?
A. Olfactory receptor cells are bipolar neurons that are not replaced when damaged.
230. The portion(s) of the tongue that actually perceives taste is/are the:
D. taste buds
231. How do the senses of smell and taste differ?
A. They differ in the types of receptors they employ.
232. Why do odors sometimes alter our moods?
A. Because sensory input from olfaction is routed through the limbic system.
233. Loss of the sensation of taste is referred to as:
B. ageusia
234. The chamber that actually houses the hearing receptors is the:
D. cochlear duct
235. After the inner ear has detected vibrations caused by sound, how is the energy dissipated?
A. perilymph inside the scala tympani absorbs the sound wave energy.
236. The organs of static equilibrium are located within the and employ shifting to set up nerve impulses.
B. vestibule; otoliths
237. The inner surface of the eyelids is lined with:
A. conjunctiva
238. The region on the retina that produces the sharpest vision is called the:
C. fovea centralis
239. Objects are perceived by photoreceptors because the rods or cones as their in the presence of light.
B. hyperpolarize; pigments decompose
240. The ability to sense body position is related to receptors.
D. proprioceptors
241. The area of the brain that integrates proprioceptor data is the:
C. cerebellum
242. Most olfactory receptors are located on the surface of the nasal cavity.
A. superior
243. Which muscle moves the eye toward the midline?
C. medial rectus
244. Which extrinsic eye muscle rotates the eyes clockwise?
A. inferior oblique
245. Which cranial nerve does not innervate eye muscles?
D. II
246. The is a membrane covering the anterior portion of the eyeball except for the cornea.
B. conjunctiva
247. Which of these is the last in the tear flow sequence?
B. nasolacrimal duct
248. The actual receptors for hearing and balance are:
D. hair cells
249. The auditory canal is part of the:
C. outer ear
250. Which is the last structure to vibrate in this sequence?
B. oval window
250. Which is the last structure to vibrate in this sequence?
Answer: C. stapes
Explanation: The stapes is the last ossicle to vibrate before transmitting sound to the oval window.
251. Bipolar neurons associated with sensory receptors are found in the
Answer: A. retina
Explanation: Bipolar neurons are found in the retina, where they transmit visual information from photoreceptors to ganglion cells.
252. Which of the following is not a primary taste sensation?
Answer: C. pungent
Explanation: The primary taste sensations are sweet, salty, sour, bitter, and umami; pungent is not one of them.
253. The olfactory receptors are examples of
Answer: C. chemoreceptors
Explanation: Olfactory receptors detect chemicals in the air, classifying them as chemoreceptors.
254. The external auditory meatus passes through the
Answer: C. temporal bone
Explanation: The external auditory meatus is a canal in the temporal bone of the skull.
255. Which of the following helps maintain proper air pressure in the middle ear?
Answer: B. Eustachian tube
Explanation: The Eustachian tube regulates air pressure in the middle ear by connecting it to the nasopharynx.
256. Endolymph is found within the
Answer: C. cochlear duct
Explanation: Endolymph is the fluid that fills the cochlear duct in the inner ear.
257. Which of the following generates a receptor potential in hair cells?
Answer: C. bending of stereocilia
Explanation: The bending of stereocilia on hair cells triggers a receptor potential, essential for hearing and balance.
258. The round window connects to the
Answer: A. scala tympani
Explanation: The round window is part of the cochlea and connects to the scala tympani, allowing for the displacement of fluid during sound transmission.
259. Nerve fibers that synapse with hair cells in the organ of Corti unite to form part of the nerve
Answer: D. vestibulocochlear
Explanation: The vestibulocochlear nerve (cranial nerve VIII) carries auditory information from the organ of Corti to the brain.
260. Which of the following represents the correct pathway leading to the perception of sound?
Answer: B. tympanic membrane, ossicles, perilymph, endolymph, hair cells
Explanation: Sound waves travel from the tympanic membrane to the ossicles, through perilymph and endolymph, and ultimately stimulate hair cells.
261. Which of the following is associated with equilibrium?
Answer: C. otolithic membrane
Explanation: The otolithic membrane in the inner ear plays a critical role in detecting linear acceleration and gravity, contributing to equilibrium.
262. Otoliths are
Answer: A. crystals
Explanation: Otoliths are small crystals found in the otolithic membrane, which help detect gravity and linear motion.
263. Which of the following is part of the vascular tunic of the eye?
Answer: C. choroid
Explanation: The choroid is a layer of blood vessels in the vascular tunic that provides nutrients to the retina.
264. When entering a dark room on a sunny day, it takes some time to be able to see because
Answer: A. it takes time for the retina to rebuild its rhodopsin
Explanation: The transition from bright to dim light requires time for the rods to regenerate their photopigment, rhodopsin.
265. Each crista in the semicircular ducts is covered by a gelatinous material called the
Answer: C. cupula
Explanation: The cupula is a gelatinous structure that covers the crista in the semicircular ducts and moves in response to head movement.
266. The anterior cavity contains
Answer: B. aqueous humor
Explanation: The anterior cavity of the eye contains aqueous humor, which nourishes the lens and cornea.
267. The point of greatest visual acuity is the
Answer: D. central fovea
Explanation: The central fovea of the retina has the highest concentration of cones, responsible for sharp central vision.
268. Intraocular pressure is primarily due to the
Answer: A. aqueous humor
Explanation: The aqueous humor maintains intraocular pressure by circulating within the anterior chamber of the eye.
269. As they extend from the retina to the brain, nerve fibers
Answer: A. from the nasal half of each retina cross to reach the opposite visual cortex
Explanation: Nerve fibers from the nasal retina cross at the optic chiasm to reach the opposite side of the brain.
270. Which cranial nerve carries visual impulses to the brain?
Answer: B. II
Explanation: The optic nerve (cranial nerve II) carries visual information from the retina to the brain.
271. Aqueous humor drains from the anterior chamber into the
Answer: D. canal of Schlemm
Explanation: The canal of Schlemm is responsible for draining aqueous humor from the anterior chamber of the eye.
272. Sound waves are translated into nerve impulses in the
Answer: A. cochlea
Explanation: The cochlea converts sound vibrations into electrical signals that are sent to the brain.
273. A reflex reaction to loud sounds prevents damage to the inner ear. This reaction is due to contraction of
Answer: B. tensor tympani & stapedius muscles
Explanation: The tensor tympani and stapedius muscles contract to reduce the intensity of loud sounds and protect the inner ear.
274. The oval window connects to the
Answer: D. stapes
Explanation: The stapes transmits vibrations from the ossicles to the oval window, initiating sound transmission into the cochlea.
275. As a result of an injury, a person cannot see at all with the left eye, but has no trouble seeing with the right eye. The injury has probably severed the
Answer: C. left optic nerve
Explanation: The optic nerve transmits visual information from each eye; severing the left optic nerve results in loss of vision in the left eye.
276. Pitch is
Answer: A. the frequency of a sound vibration
Explanation: Pitch refers to how high or low a sound is, based on the frequency of its vibrations.
277. The blind spot is the area where
Answer: C. the optic nerve exits the eye
Explanation: The blind spot is the region where the optic nerve leaves the retina, lacking photoreceptor cells.
278. Perilymph fills the
Answer: B. bony labyrinth
Explanation: Perilymph is the fluid that fills the bony labyrinth of the inner ear, surrounding the membranous labyrinth.
279. Sensory stimulation to the posterior 1/3 of the tongue is conducted by the
Answer: B. glossopharyngeal nerve
Explanation: The glossopharyngeal nerve (cranial nerve IX) transmits sensory information from the posterior part of the tongue.
280. Which of the following conditions is not related to lens pathology?
Answer: A. glaucoma
Explanation: Glaucoma affects the optic nerve and intraocular pressure, not the lens of the eye.
281. The blood corpuscles are of kinds.
Answer: B. 4
Explanation: There are four main types of blood cells: red blood cells, white blood cells, platelets, and plasma.
282. Blood is stained with stain.
Answer: C. Leishman stain
Explanation: Leishman stain is commonly used to stain blood samples for microscopic examination.
283. Process of formation of blood corpuscles is called
Answer: C. Haemopoiesis
Explanation: Haemopoiesis is the process of forming blood cells in the bone marrow.
284. Graveyard of RBC is
Answer: A. Spleen
Explanation: The spleen is responsible for removing old red blood cells from circulation.
285. Which leucocytes release heparin and histamine in blood?
Answer: B. Basophil
Explanation: Basophils release heparin and histamine, which are involved in inflammatory and allergic responses.
286. Which blood cells secrets antibody?
Answer: C. Lymphocytes
Explanation: Lymphocytes, particularly B cells, secrete antibodies as part of the immune response.
287. Vitamin essential for blood clotting is
Answer: A. Vitamin K
Explanation: Vitamin K is necessary for the synthesis of clotting factors involved in the coagulation process.
288. Hemoglobin is a
Answer: B. Respiratory pigment
Explanation: Hemoglobin is the respiratory pigment that carries oxygen in red blood cells.
289. Absence of which clotting factor leads to Hemophilia-A?
Answer: B. Factor VIII
Explanation: Hemophilia-A is caused by a deficiency in clotting factor VIII.
290. What prevents clotting of blood inside blood vessels?
Answer: A. Heparin
Explanation: Heparin is an anticoagulant that helps prevent clot formation inside blood vessels.
291. In humans, both eyes focus on only one set of objects. This is called
Answer: C. binocular vision
Explanation: Binocular vision allows both eyes to focus on the same object, providing depth perception.
292. **Circumvallate papillae are
located on the**
Answer: B. posterior part of the tongue
Explanation: Circumvallate papillae are large papillae located near the back of the tongue, containing taste buds.
293. The white of the eye, which gives shape to the eyeball, makes it more rigid, and protects its inner parts is the
Answer: B. sclera
Explanation: The sclera is the white, tough outer layer of the eyeball that maintains its shape and provides protection to the inner structures.
294. Most of the refraction of light entering the eye occurs at the
Answer: B. cornea
Explanation: The cornea, being the transparent outer layer of the eye, is primarily responsible for bending (refracting) light as it enters the eye.
295. During accommodation for near vision
Answer: C. the lens increases in curvature
Explanation: During accommodation, the lens becomes more curved to focus on nearby objects by increasing its curvature.
296. Constriction of the pupil is brought about by contraction of the
Answer: B. circular muscle of the iris
Explanation: The circular muscles of the iris contract in response to bright light, causing the pupil to constrict.
297. Photopigment in the rods and cones is imbedded in the
Answer: D. membrane folds of the outer segment of these cells
Explanation: Photopigments, responsible for light absorption, are embedded in the membrane folds of the outer segments of rods and cones.
298. The most common type of color blindness is
Answer: B. red-green color blindness
Explanation: Red-green color blindness is the most common form of color vision deficiency, affecting the perception of red and green hues.
299. In daylight, rods contribute little to vision because
Answer: C. the rhodopsin is bleached as fast as it is regenerated
Explanation: In bright light, the photopigment rhodopsin in rods becomes bleached and cannot regenerate quickly enough, limiting their function.
300. When light hits the rods
Answer: A. Na+ channels close and less inhibitory neurotransmitter is released
Explanation: When light activates rods, sodium channels close, leading to a reduction in inhibitory neurotransmitter release and the initiation of visual signals.
301. Which layer of the heart is responsible for contraction?
Answer: B. Myocardium
Explanation: The myocardium is the thick muscular layer of the heart responsible for contraction and pumping blood.
302. What is the function of the semilunar valves?
Answer: B. To allow blood to flow from ventricles to arteries
Explanation: The semilunar valves (pulmonary and aortic) allow blood to flow from the ventricles into the arteries while preventing backflow.
304. The pacemaker of the heart is the:
Answer: B. Sinoatrial (SA) node
Explanation: The SA node is the natural pacemaker of the heart, initiating electrical impulses that regulate heart rate.
305. Which blood vessel carries oxygenated blood to the heart?
Answer: A. Pulmonary vein
Explanation: The pulmonary vein carries oxygenated blood from the lungs to the left atrium of the heart.
306. Which of the following conditions results in insufficient blood supply to the heart muscle?
Answer: B. Myocardial infarction
Explanation: Myocardial infarction, commonly known as a heart attack, occurs when blood flow to a part of the heart muscle is blocked, leading to tissue damage.
307. Which chamber of the heart pumps oxygenated blood to the rest of the body?
Answer: D. Left ventricle
Explanation: The left ventricle pumps oxygenated blood through the aorta to the rest of the body.
308. Blood returning from the lungs enters which chamber of the heart?
Answer: C. Left atrium
Explanation: Oxygenated blood returning from the lungs enters the left atrium before being pumped into the left ventricle.
The primary function of red blood cells in the cardiovascular system is:
Answer: B. Oxygen transport
Explanation: Red blood cells (RBCs) are responsible for transporting oxygen from the lungs to tissues and organs throughout the body, as well as carrying carbon dioxide back to the lungs.
Which blood vessel has the thickest walls to withstand high pressure?
Answer: C. Arteries
Explanation: Arteries have thick muscular walls to withstand the high pressure generated when the heart pumps blood through them.
The "lub" sound of the heart is caused by:
Answer: C. The closing of the atrioventricular valves
Explanation: The "lub" sound (first heart sound) is produced by the closure of the atrioventricular (AV) valves (mitral and tricuspid valves) during ventricular contraction.
What is the normal range of the heart rate in adults?
Answer: B. 60–100 bpm
Explanation: The normal resting heart rate for adults is typically between 60 and 100 beats per minute (bpm).
Which of the following is a risk factor for atherosclerosis?
Answer: B. Smoking
Explanation: Smoking is a major risk factor for atherosclerosis, as it can damage the lining of blood vessels and promote the buildup of plaque.
What is the term for the volume of blood pumped by the heart per minute?
Answer: B. Cardiac output
Explanation: Cardiac output is the amount of blood the heart pumps per minute, calculated as the stroke volume multiplied by the heart rate.
Which artery is most commonly used to measure blood pressure?
Answer: C. Brachial artery
Explanation: Blood pressure is typically measured at the brachial artery, located in the upper arm.
The heart is located in which cavity?
Answer: A. Thoracic cavity
Explanation: The heart is located in the thoracic cavity, specifically in the mediastinum, between the lungs.
During systole, the heart:
Answer: A. Contracts to pump blood
Explanation: During systole, the heart contracts, pumping blood out of the ventricles into the arteries.
Which ion is crucial for cardiac muscle contraction?
Answer: C. Calcium
Explanation: Calcium ions play a key role in cardiac muscle contraction by facilitating the interaction between actin and myosin filaments in muscle fibers.
Pulmonary circulation is responsible for:
Answer: C. Transporting deoxygenated blood to the lungs
Explanation: Pulmonary circulation involves the movement of deoxygenated blood from the right side of the heart to the lungs, where it is oxygenated before returning to the left side of the heart.
Which part of the brain regulates heart rate?
Answer: B. Medulla oblongata
Explanation: The medulla oblongata controls autonomic functions, including heart rate, by sending signals to the heart via the sympathetic and parasympathetic nervous systems.
Which diagnostic test measures the electrical activity of the heart?
Answer: B. Electrocardiogram (ECG)
Explanation: An electrocardiogram (ECG) records the electrical activity of the heart, helping diagnose heart conditions like arrhythmias and heart attacks.
Which structure prevents the backflow of blood from the left ventricle to the left atrium?
Answer: B. Mitral valve
Explanation: The mitral valve (also known as the bicuspid valve) prevents blood from flowing backward from the left ventricle into the left atrium during ventricular contraction.
Coronary arteries primarily supply blood to:
Answer: C. The heart muscle
Explanation: The coronary arteries supply oxygenated blood to the heart muscle (myocardium), ensuring the heart can function effectively.
Which term refers to the pressure exerted by blood against the walls of blood vessels?
Answer: C. Blood pressure
Explanation: Blood pressure is the force of blood against the walls of blood vessels, which is essential for circulating blood throughout the body.
Which of the following is an effect of the sympathetic nervous system on the heart?
Answer: B. Increase in heart rate
Explanation: The sympathetic nervous system stimulates the heart to beat faster and stronger, especially during stress or physical activity.
What does the P wave on an electrocardiogram (ECG) represent?
Answer: A. Atrial depolarization
Explanation: The P wave represents the electrical activity associated with the depolarization (contraction) of the atria.
Which structure separates the left and right sides of the heart?
Answer: C. Interventricular septum
Explanation: The interventricular septum separates the left and right ventricles, preventing the mixing of oxygenated and deoxygenated blood.
Which heart condition is characterized by a rapid, irregular heart rhythm?
Answer: C. Atrial fibrillation
Explanation: Atrial fibrillation is a condition where the atria beat irregularly and rapidly, leading to an inefficient blood flow.
Which hormone increases heart rate and cardiac output during stress?
Answer: C. Epinephrine
Explanation: Epinephrine (adrenaline) is released during stress, increasing heart rate and cardiac output as part of the "fight or flight" response.
What is the average resting cardiac output in a healthy adult?
Answer: C. 5 liters per minute
Explanation: The average resting cardiac output is about 5 liters per minute in a healthy adult, which is the amount of blood the heart pumps through the circulatory system each minute.
Which diagnostic tool uses ultrasound to assess heart structure and function?
Answer: B. Echocardiogram
Explanation: An echocardiogram uses ultrasound waves to create images of the heart's structure and assess its function.
Which structure is the primary site of gas exchange in the lungs?
Answer: B. Alveoli
Explanation: Alveoli are tiny air sacs in the lungs where oxygen and carbon dioxide are exchanged between the air and the bloodstream.
What is the primary muscle responsible for inhalation?
Answer: C. Diaphragm
Explanation: The diaphragm is the primary muscle that contracts and flattens to allow air to enter the lungs during inhalation.
The trachea branches into two:
Answer: C. Primary bronchi
Explanation: The trachea divides into two primary bronchi, which lead air into the left and right lungs.
What structure prevents food from entering the trachea?
Answer: A. Epiglottis
Explanation: The epiglottis is a flap of tissue that covers the trachea during swallowing, preventing food and liquids from entering the airway.
Which lung has three lobes?
Answer: A. Right lung
Explanation: The right lung has three lobes, while the left lung has two lobes to accommodate the heart.
The exchange of oxygen and carbon dioxide between the blood and the alveoli is called:
Answer: C. External respiration
Explanation: External respiration refers to the exchange of gases (oxygen and carbon dioxide) between the alveoli and the blood.
What is the normal respiratory rate for an adult at rest?
Answer: B. 12–20 breaths per minute
Explanation: The normal respiratory rate for an adult at rest is between 12 and 20 breaths per minute.
Which structure warms, moistens, and filters air as it is inhaled?
Answer: B. Nasal cavity
Explanation: The nasal cavity is lined with mucous membranes and tiny hairs that filter, warm, and moisten the air before it reaches the lungs.
Which of the following is a component of the upper respiratory system?
Answer: A. Larynx
Explanation: The larynx, located in the upper respiratory system, plays a key role in protecting the airway, producing sound, and facilitating breathing.
The pleura that directly covers the lungs is called the:
Answer: B. Visceral pleura
Explanation: The visceral pleura is the membrane that directly covers the lungs, providing a protective layer.
Which gas is the primary driver of respiration?
Answer: B. Carbon dioxide
Explanation: The concentration of carbon dioxide in the blood is the main factor regulating breathing rate and depth.
What is the primary function of the respiratory system?
Answer: B. Gas exchange
Explanation: The main function of the respiratory system is to facilitate gas exchange, supplying oxygen to the body and removing carbon dioxide.
Which part of the brain regulates breathing?
Answer: C. Medulla oblongata
Explanation: The medulla oblongata controls the rate and depth of breathing by responding to changes in carbon dioxide levels in the blood.
Which of the following is a characteristic of the right bronchus compared to the left?
Answer: B. Wider and shorter
Explanation: The right bronchus is wider, shorter, and more vertical than the left, making it more likely for foreign objects to enter.
The amount of air inhaled or exhaled during a normal breath is called:
Answer: B. Tidal volume
Explanation: Tidal volume is the amount of air that moves in and out of the lungs during a normal breath.
What is the purpose of surfactant in the lungs?
Answer: B. To reduce surface tension
Explanation: Surfactant reduces surface tension in the alveoli, preventing them from collapsing and facilitating easier breathing.
During exhalation, the diaphragm:
Answer: B. Relaxes and moves upward
Explanation: During exhalation, the diaphragm relaxes and moves upward, helping to expel air from the lungs.
Oxygen is primarily transported in the blood:
Answer: B. Bound to hemoglobin
Explanation: Oxygen is mainly transported in the blood bound to hemoglobin in red blood cells.
What is hypoxia?
Answer: B. Reduced oxygen supply to tissues
Explanation: Hypoxia is a condition where there is a deficiency of oxygen in the tissues, which can lead to various health problems.
Which condition is characterized by chronic inflammation and narrowing of the airways?
Answer: A. Asthma
Explanation: Asthma is a chronic condition that causes inflammation and narrowing of the airways, making breathing difficult.
The vocal cords are located in the:
Answer: B. Larynx
Explanation: The vocal cords are located in the larynx, where they vibrate to produce sound.
Which part of the respiratory system is shared with the digestive system?
Answer: B. Pharynx
Explanation: The pharynx is a shared passage for both food and air, leading to the larynx and esophagus.
The maximum amount of air a person can exhale after a maximum inhalation is called:
Answer: C. Vital capacity
Explanation: Vital capacity is the maximum amount of air that can be exhaled after a full inhalation, including tidal volume, inspiratory reserve, and expiratory reserve volumes.
Carbon dioxide is primarily transported in the blood:
Answer: C. As bicarbonate ions
Explanation: The majority of carbon dioxide is transported in the blood as bicarbonate ions, after being converted in red blood cells.
What is the medical term for difficulty breathing?
Answer: B. Dyspnea
Explanation: Dyspnea refers to the sensation of difficult or labored breathing.
Which respiratory disease is caused by Mycobacterium tuberculosis?
Answer: B. Tuberculosis
Explanation: Tuberculosis is an infectious disease caused by Mycobacterium tuberculosis, primarily affecting the lungs.
The flap of tissue that closes over the trachea during swallowing is the:
Answer: C. Epiglottis
Explanation: The epiglottis prevents food and liquid from entering the trachea during swallowing.
The total lung capacity includes:
Answer: B. Vital capacity and residual volume
Explanation: Total lung capacity includes the vital capacity (maximum air expelled) plus the residual volume (air remaining after full exhalation).
What happens to oxygen levels in the blood during hyperventilation?
Answer: A. Increase
Explanation: During hyperventilation, rapid breathing leads to increased oxygen intake, but it can also cause reduced carbon dioxide levels, leading to an imbalance.
Which of the following best describes pulmonary edema?
Answer: B. Fluid accumulation in the alveoli
Explanation: Pulmonary edema is a condition where fluid accumulates in the alveoli, impairing gas exchange and leading to difficulty breathing.
A patient experiences significant blood loss after an injury. Which cardiovascular mechanism will compensate to maintain blood pressure?
Answer: C. Vasoconstriction of blood vessels
Explanation: Vasoconstriction helps maintain blood pressure by narrowing the blood vessels, compensating for blood loss.
During exercise, a person’s heart rate and cardiac output increase. Which part of the autonomic nervous system is primarily responsible for this response?
Answer: B. Sympathetic nervous system
Explanation: The sympathetic nervous system is responsible for increasing heart rate and cardiac output during physical activity.
If a person has a blockage in the coronary arteries, which layer of the heart will be most affected?
Answer: B. Myocardium
Explanation: The myocardium, the heart muscle layer, will be most affected by a blockage in the coronary arteries, leading to ischemia and potential heart damage.
A patient's blood pressure is measured as 145/90 mmHg. Which part of the cardiovascular system is directly responsible for the diastolic reading?
Answer: C. Peripheral resistance in the arteries
Explanation: The diastolic reading reflects the resistance in the arteries when the heart is at rest between beats.
A person accidentally inhales a small object. It lodges in the right bronchus. How does this relate to the anatomy of the cardiovascular system?
Answer: B. Reduced oxygenation in the right lung impacts blood returning to the left atrium.
Explanation: Inhaled objects blocking the right bronchus can reduce oxygenation in the right lung, which can affect the overall oxygen content of the blood returned to the heart.
A blood clot forms in a deep vein of the leg. Which structure prevents it from traveling to the brain?
Answer: C. Pulmonary capillaries
Explanation: The pulmonary capillaries filter out blood clots, preventing them from traveling to the brain.
If the sinoatrial (SA) node fails to generate an impulse, which structure takes over as the secondary pacemaker?
Answer: B. Atrioventricular (AV) node
Explanation: The AV node takes over as the secondary pacemaker if the SA node fails, ensuring continued heart rhythm.
A patient has swelling in the lower extremities due to venous insufficiency. What cardiovascular mechanism contributes to this condition?
Answer: B. Failure of venous valves to prevent backflow
Explanation: Venous insufficiency occurs when venous valves fail, allowing blood to flow backward and accumulate, causing swelling.
A person is diagnosed with aortic regurgitation. Which phase of the cardiac cycle is directly affected by this condition?
Answer: A. Ventricular diastole
Explanation: Aortic regurgitation affects ventricular diastole, as blood flows back into the left ventricle, increasing the volume during diastole.
A patient has anemia, resulting in decreased oxygen delivery to tissues. Which component of the cardiovascular system is primarily responsible for this reduced oxygenation?
Answer: c. Red blood cells
Explanation: Red blood cells contain hemoglobin, which is responsible for transporting oxygen throughout the body. In anemia, the number of red blood cells or hemoglobin levels are reduced, leading to decreased oxygen delivery to tissues.
A patient is breathing rapidly and deeply after strenuous exercise. Which mechanism explains this increase in respiration?
Answer: c. Accumulation of lactic acid in the blood
Explanation: Strenuous exercise can lead to anaerobic metabolism, causing lactic acid buildup in the blood. The body increases respiration to expel excess carbon dioxide and restore normal pH levels.
A person is choking on food, and air cannot pass through the airway. Which structure is most likely obstructed?
Answer: b. Trachea
Explanation: The trachea is the primary airway that carries air to the lungs. Obstruction here would prevent air from entering the lungs during choking.
A scuba diver ascends too quickly, causing nitrogen bubbles to form in their blood. Which structure must work efficiently to remove these gases?
Answer: a. Alveoli
Explanation: The alveoli in the lungs exchange gases like oxygen and carbon dioxide. Efficient alveolar function is necessary to remove excess nitrogen that forms during rapid ascension from a dive.
A patient with emphysema has reduced elasticity of the lungs. Which process of respiration is most affected?
Answer: c. Exhalation due to elastic recoil
Explanation: Emphysema damages the alveoli and reduces the lungs' ability to recoil during exhalation, making it harder to expel air from the lungs.
A young child accidentally inhales a small toy. Why is the object more likely to lodge in the right bronchus than the left?
Answer: b. The right bronchus is shorter and more vertical than the left.
Explanation: The right bronchus is more direct and vertical compared to the left, making it a more likely path for inhaled objects.
A patient with pneumonia has fluid accumulation in the alveoli. How does this affect gas exchange?
Answer: b. It decreases surface area for oxygen and carbon dioxide exchange.
Explanation: Fluid in the alveoli reduces the effective surface area for gas exchange, impairing oxygen uptake and carbon dioxide removal.
After a severe car accident, a patient has a puncture wound to the chest. Air is entering the pleural cavity, causing lung collapse. What is this condition called?
Answer: d. Pneumothorax
Explanation: Pneumothorax occurs when air enters the pleural cavity, causing the lung to collapse due to the loss of negative pressure.
A patient has a respiratory rate of 8 breaths per minute, and their oxygen saturation is decreasing. What is the physiological explanation for this?
Answer: b. Reduced alveolar ventilation and carbon dioxide removal
Explanation: A low respiratory rate reduces the amount of air entering the lungs, decreasing the oxygen available for exchange and impairing the removal of carbon dioxide.
A patient with asthma has narrowing of their airways due to bronchospasm. Which part of the respiratory system is primarily affected?
Answer: b. Bronchioles
Explanation: In asthma, the bronchioles constrict, leading to difficulty in airflow and reduced oxygen intake.
A patient is diagnosed with chronic obstructive pulmonary disease (COPD) and has difficulty exhaling completely. Which characteristic of the lungs contributes to this issue?
Answer: b. Loss of alveolar elasticity
Explanation: COPD damages the alveolar walls, reducing their elasticity, which impairs the lung's ability to expel air efficiently during exhalation.
A patient is found to have a low hematocrit level. What is the most likely consequence of this condition?
Answer: b. Reduced oxygen-carrying capacity of the blood
Explanation: A low hematocrit means a reduced number of red blood cells, which decreases the blood's ability to carry oxygen.
A person is injured and begins to bleed profusely. Which blood component will play the primary role in forming a clot?
Answer: c. Platelets
Explanation: Platelets are crucial in forming blood clots to prevent excessive bleeding after an injury.
A patient with a bacterial infection has an elevated white blood cell (WBC) count. Which type of WBC is most likely responsible for this increase?
Answer: a. Neutrophils
Explanation: Neutrophils are the first line of defense against bacterial infections and are typically elevated during bacterial infections.
A person living at high altitudes develops an increased red blood cell count. What physiological mechanism explains this adaptation?
Answer: a. Reduced oxygen levels stimulate erythropoietin release.
Explanation: Lower oxygen levels at high altitudes stimulate the kidneys to release erythropoietin, which stimulates red blood cell production to increase oxygen-carrying capacity.
A patient with a swollen lymph node in the neck reports a sore throat. What is the role of the lymph node in this situation?
Answer: b. Filtering pathogens and producing immune cells
Explanation: Lymph nodes filter pathogens from the lymphatic fluid and produce immune cells to fight infections like sore throats.
A patient with liver disease has impaired production of albumin. Which consequence is most likely?
Answer: c. Fluid accumulation in tissues (edema)
Explanation: Albumin helps maintain osmotic pressure in the blood vessels. Without it, fluid leaks into tissues, causing edema.
A person with a deep cut receives a tetanus shot. Why is this injection given in the muscle and not the bloodstream?
Answer: a. To ensure slower absorption for prolonged immunity
Explanation: Injecting the vaccine into the muscle allows for slower absorption, providing longer-lasting immunity compared to rapid absorption through the bloodstream.
A patient diagnosed with lymphedema has swelling in one arm. Which component of the lymphatic system is not functioning properly?
Answer: b. Lymph vessels
Explanation: Lymphedema is caused by blockage or malfunction in the lymph vessels, preventing proper drainage of lymph and leading to swelling.
A patient has a deficiency in vitamin K. How will this affect the blood?
Answer: b. Impaired blood clotting
Explanation: Vitamin K is essential for the synthesis of clotting factors, so a deficiency impairs the blood's ability to clot properly.
A person is bitten by a mosquito carrying pathogens. Which structure in the lymphatic system is primarily responsible for detecting and responding to the infection?
Answer: c. Lymph nodes
Explanation: Lymph nodes filter lymph and detect pathogens, playing a key role in immune responses to infections.
A patient has a blockage in the common bile duct. Which digestive process is most likely impaired?
Answer: c. Digestion of fats in the small intestine
Explanation: The common bile duct delivers bile to the small intestine, which is essential for the digestion of fats. Blockage impairs fat digestion.
A person undergoes surgery to remove part of their stomach. How might this affect the production of intrinsic factor, and what is the consequence?
Answer: b. Decreased intrinsic factor causing vitamin B12 deficiency
Explanation: Intrinsic factor, produced in the stomach, is essential for vitamin B12 absorption. Removal of part of the stomach can lead to vitamin B12 deficiency.
A patient with a hiatal hernia experiences acid reflux. What is the anatomical cause of this condition?
Answer: b. Displacement of the stomach through the diaphragm
Explanation: A hiatal hernia occurs when part of the stomach pushes through the diaphragm, allowing acid to reflux into the esophagus, leading to heartburn.
A person has damage to the villi of the small intestine due to celiac disease. Which function of the digestive system is most affected?
Answer: c. Absorption of nutrients
Explanation: Damage to the villi reduces the surface area for nutrient absorption in the small intestine, leading to malabsorption.
A patient with gallstones experiences severe pain after eating fatty foods. Which digestive organ is primarily affected?
Answer: c. Gallbladder
Explanation: The gallbladder stores bile, which helps digest fats. Gallstones can block bile flow, causing pain, especially after fatty meals.
A couple is trying to conceive, but the woman has a blockage in her fallopian tubes. What process is directly hindered?
Answer: b. Fertilization
Explanation: The fallopian tubes are where fertilization typically occurs. A blockage prevents sperm from reaching the egg.
A male patient has an injury to the testes that damages Leydig cells. Which hormone will be most affected?
Answer: a. Testosterone
Explanation: Leydig cells in the testes produce testosterone. Damage to these cells reduces testosterone production.
During childbirth, the doctor notices the cervix is not fully dilated. What stage of labor is the patient in?
Answer: a. First stage
Explanation: The first stage of labor involves cervical dilation and effacement, leading up to the delivery.
A woman has a hormonal imbalance leading to an insufficient luteal phase. Which process is most likely disrupted?
Answer: c. Maintenance of the endometrium
Explanation: The luteal phase involves the secretion of progesterone, which is crucial for maintaining the endometrial lining for implantation. Insufficient progesterone can prevent the proper maintenance of the endometrium, hindering implantation.
A patient undergoes a vasectomy. Which structure in the male reproductive system is severed during this procedure?
Answer: b. Vas deferens
Explanation: The vas deferens is the tube that carries sperm from the testes to the urethra. In a vasectomy, this tube is cut or sealed to prevent sperm from being released during ejaculation.