Physiology - Module 15B 2026 Ratio

C. bitemporal hemianopia

A 35-year-old lady complaining of headache claims that she has been bumping on to side tables frequently for the past 3 months. On examination, she has a reduced ability to see objects in the temporal visual fields of both eyes. The diagnosis is

A. homonymous hemianopia

B. central scotoma

C. bitemporal hemianopia

D. retinopathy

B. Fovea

Which region of the retina has the greatest concentration of cones?

A. Parafoveal region

B. Fovea

C. Iris

D. Optic disc

D. recessive gene on the X chromosome

A 10-year-old boy was having difficulty with school mainly when he reads charts and graphs presented in front of the class. He was assessed by the school physician and on the Snellen chart, his visual acuity is 20/20 but he was also asked to identify numbers in an Ishihara chart. He responded that he merely saw a bunch of dots. Abnormal color vision is 20 times more common in males than females because most cases are caused by an abnormal

A. dominant gene on the Y chromosome

B. dominant gene on the X chromosome

C. recessive gene on the Y chromosome

D. recessive gene on the X chromosome

D. right calcarine cortex

A 50-year-old man presented with sudden onset visual loss. He was rushed to the ER and on examination he had a left homonymous hemianopia. Which part of the visual field is most likely affected?

A. right optic nerve

B. left calcarine cortex

C. left optic nerve

D. right calcarine cortex

D. presbyopia

A 65-year-old man who had never needed to wear glasses had trouble reading a menu in a dimly-lit restaurant. He then recalled that as of late he needed to have the newspaper closer to his eyes to read it.

What would be the most likely condition for this patient?

A. Hyperopia

B. optic atrophy

C. color blindness

D. presbyopia

C. the inability to increase the refractive power of the lens

A 65-year-old man who had never needed to wear glasses had trouble reading a menu in a dimly-lit restaurant. He then recalled that as of late he needed to have the newspaper closer to his eyes to read it.

What would be the most likely mechanism for his condition?

A. the inability to increase the relaxation of the sphincter muscle of the iris

B. the inability to increase the tension on the suspensory ligaments

C. the inability to increase the refractive power of the lens

D. the inability to increase the contraction of the ciliary muscle

B. refractive power is at 20 diopters

A 65-year-old man who had never needed to wear glasses had trouble reading a menu in a dimly-lit restaurant. He then recalled that as of late he needed to have the newspaper closer to his eyes to read it.

In a normal situation at rest, which of the following is true about accommodation?

A. ciliary muscles contract

B. refractive power is at 20 diopters

C. lens are more spherical

D. suspensory ligaments are relaxed

A. ciliary ganglion

A 65-year-old man who had never needed to wear glasses had trouble reading a menu in a dimly-lit restaurant. He then recalled that as of late he needed to have the newspaper closer to his eyes to read it.

Which of the following structures is involved in the control of ciliary muscles?

A. ciliary ganglion

B. abducens nucleus

C. Pons

D. medial longitudinal fasciculus

A. structural changes in rhodopsin, activation of transducin, decrease in intracellular cGMP, closure of cGMP-gated cation channels, and hyperpolarization

Which of the following is the correct sequence of events involved in phototransduction in rods and cones in response to light?

A. structural changes in rhodopsin, activation of transducin, decrease in intracellular cGMP, closure of cGMP-gated cation channels, and hyperpolarization

B. hyperpolarization, activation of transducin, closure of cGMP-gated cation channels,decrease in intracellular cGMP, and structural changes in rhodopsin

C. structural changes in rhodopsin, decrease in intracellular cGMP, hyperpolarization, closure of cGMP-gated cation channels, and activation of transducin

D. activation of transducin, hyperpolarization, structural changes in rhodopsin, closure ofcGMP-gated cation channels, and decrease in intracellular cGMP.

D. each cone synapses on a single bipolar cell, which, in turn, synapses on a single ganglion cell that terminates in the lateral geniculate body.

Which of the following explains the connections from the cone receptor to the visual cortex?

A. each cone synapses on a single ganglion cell, which in turn synapses on a horizontal cell that projects direct pathway from the retina to the primary visual cortex.

B. each cone synapses on a single horizontal cell, which, in turn, synapses on a single ganglion cell, providing a direct pathway from the retina to the lateral geniculate body.

C. each cone synapses on a single bipolar cell, which, in turn, synapses on a single ganglion cell, providing a direct pathway from the retina to the primary visual cortex

D. each cone synapses on a single bipolar cell, which, in turn, synapses on a single ganglion cell that terminates in the lateral geniculate body.

C. right optic tract

A visual exam in a 45-year-old woman shows blindness in the temporal visual field of the right eye and the nasal visual field of the left eye. This visual defect could result from a lesion of the

A. optic chiasm

B. left lateral geniculate nucleus

C. right optic tract

D. the left optic nerve

B. fibers from each nasal hemiretina decussate in the optic chiasm, so that the fibers in the right optic tract are those from the nasal half of left retina and the temporal half of the right retina.

Which parts of the visual field of each eye are relayed through the right optic tract?

A. fibers from each nasal hemiretina decussate in the optic chiasm, so that the fibers in the right optic tract are those from the nasal half of right retina and the temporal half of the left retina.

B. fibers from each nasal hemiretina decussate in the optic chiasm, so that the fibers in the right optic tract are those from the nasal half of left retina and the temporal half of the right retina.

C. fibers from each temporal hemiretina decussate in the optic chiasm, so that the fibers in the right optic tract are those from the temporal half of left retina and the nasal half of the right retina

D. fibers from each temporal hemiretina decussate in the optic chiasm, so that the fibers in the right optic tract are those from the temporal half of right retina and the nasal half of the left retina.

D. 20

The velocity of light in a hypothetical substance, called kryptonite, is 100km/s. If the velocity of light in air in the atmosphere of Krypton is 2000km/s, what is the refractive index of kryptonite?

A. 2000

B. 2

C. 200

D. 20

B. lens of the Last Son of Krypton

The focal length produced after light passes through kryptonite is 100 cm. On the other hand, light passing through the lens of the Last Son of Krypton has a focal length of 20 cm. Which has a greater refractive power in terms of diopters?

A. Kryptonite

B. lens of the Last Son of Krypton

C. Both

D. neither

C. Iris

Which of the following helps regulate the amount of light entering the eye?

A. ciliary muscle

B. aqueous humor

C. Iris

D. vitreous humor

C. Nothing

Which of the following ossicles is directly connected to the round window?

A. Incus

B. Stapes

C. Nothing

D. Malleus

B. It translates sound vibrations from lower density medium to a higher density medium.

Which of the following is a major function of the ossicles?

A. It prevents the rupture of the tympanic membrane

B. It translates sound vibrations from lower density medium to a higher density medium.

C. The ossicles prevent excess vibration from going through the oval window

D. It allows reduction of the sound vibration from the outside environment

D. Reissner’s Membrane

Rupture of which of the following would cause direct communication of fluids in the scala vestibuli and the scala media?

A. Basilar Membrane

B. Tectorial Membrane

C. Stria Vascularis

D. Reissner’s Membrane

B. Greater Sodium Concentration

Which of the following is true of the electrolyte concentrations in the perilymph (when compared to the endolymph)?

A. Both compartments have the same concentrations of electrolytes

B. Greater Sodium Concentration

C. Greater Potassium Concentration

D. Greater Chloride concentration

D. The higher the amplitude, the louder the sound

Which of the following is true regarding the properties of sound?

A. The higher the frequency, the higher the amplitude of a sound

B. The louder the sound, the higher the pitch

C. The higher the pitch of a sound, the higher the timbre

D. The higher the amplitude, the louder the sound

B. 60-80

A typical conversation is _____ decibels loud.

A. 90-110

B. 60-80

C. 30-40

D. 120-160

D. Broca’s Area

A 23-year-old female was rushed into the emergency room for loss of consciousness. While being stabilized, the woman gain consciousness. She follows commands but responds to questions by speaking a string of unrelated words. Which of the following may be damaged?

A. Wernicke’s Area

B. No damage

C. Auditory Cortex

D. Broca’s Area

B. Higher

When the sound frequency is lower, the threshold of hearing is:

A. Lower

B. Higher

C. Independent of the frequency

B. It masks low-frequency sounds in loud environments.

Which of the following is true of the attenuation reflex?

A. It protects the cochlea from excessively low-frequency sounds.

B. It masks low-frequency sounds in loud environments.

C. It can reduce the frequency of incoming sounds from the environment.

D. It increases the reception of high-amplitude sounds.

C. No sound

A normal individual who was exposed to a 23,000 Hz sound frequency would hear:

A. A high-pitched sound

B. A mid-pitched sound

C. No sound

D. A low-pitched sound

A. Frequency Theory

Very low perceivable sounds could be heard by the human ear could be currently best explained by which of the following?

A. Frequency Theory

B. Place Theory

C. Volley Theory

D. Trough Theory

B. Conductive hearing loss, left

A 45-year-old male consulted your clinic for hearing loss on the left. Upon examination, you had the following physical exam findings:

Weber: left > right;

Rinne: L – air conduction = bone conduction, R – air conduction > bone conduction.

These findings indicate:

A. Sensorineural hearing loss, left

B. Conductive hearing loss, left

C. Sensorineural hearing loss, right

D. Conductive hearing loss, right

D. Clockwise

A patient was spun counterclockwise and was suddenly stopped. He was then observed for nystagmus. The direction of the fast phase of the nystagmus (relative to the PATIENT) is:

A. Bilaterally fast

B. Counterclockwise

C. Bilaterally slow (no fast phase)

D. Clockwise

B. Umami – D-glutamate

Which substance to taste sensation is incorrectly paired?

A. Bitter – Quinine

B. Umami – D-glutamate

C. Sour – Hydrogen ions

D. Salty – Calcium chloride

E. Sweet – Sucrose

C. Base of tongue, Pharynx – Cranial Nerve X

Which of the following taste buds-innervation is/are correctly paired?

A. Anterior 2/3 of tongue – Cranial Nerve IX

B. Posterior 1/3 of tongue – Cranial Nerve VII

C. Base of tongue, Pharynx – Cranial Nerve X

D. All of the above

C. Sour

Which among the following taste sensations utilizes an ionotropic receptor?

A. Umami

B. Bitter

C. Sour

D. Sweet

E. Glucose

The following substances have a taste index of 1, except?

A. Sucrose

B. Quinine

C. Hydrochloric acid

D. Sodium chloride

E. Glucose

D. All of the above

The nucleus tractus solitarius receives taste inputs from which cranial nerve/s?

A. Cranial Nerve VII

B. Cranial Nerve IX

C. Cranial Nerve X

D. All of the above

C. Bitter

Which of the following taste sensation utilizes the T2R family of G-protein coupled receptors?

A. Sour

B. Salty

C. Bitter

D. Sweet

E. Umami

B. G-protein coupled receptor

Which of the following type of receptors come in contact with odorant substances?

A. Tyrosine kinase receptor

B. G-protein coupled receptor

C. Ligand-gated sodium channel

D. Adenyl cyclase receptor

B. Liquefactive substances

The following factors make it suitable for stimulation of olfaction, except?

A. Slightly lipophilic substances

B. Liquefactive substances

C. Slightly hydrophilic substances

D. Evaporative substances

B. 20 to 30 per second

Stimulation of olfaction causes depolarization of olfactory cells, increasing action potential at how many rate?

A. 50 to 100 per second

B. 20 to 30 per second

C. 1 to 5 per second

D. 5 to 20 per second

C. Feedback inhibition is facilitated thru secretion of GABA by granule cells

Which of the following statements is true of adaptation of olfaction?

A. Olfactory receptors adapt approximately 10% in the first second after stimulation

B. Mitral and tufted cells release the excitatory neurotransmitter acetylcholine

C. Feedback inhibition is facilitated thru secretion of GABA by granule cells

D. Most of the additional adaptation occurs in the brainstem

D. Methylmercaptan

Which of the following substances is usually added to natural gas to give it odor for detection of pipeline leak?

A. Methylmercury

B. Methylmethionine

C. Methylmalonate

D. Methylmercaptan

A. Lateral olfactory area

A 6 5y/o male was diagnosed with brain tumor which altered his sense of smell. Upon observation, this patient still exhibits salivary production when aroma of food is present. Which olfactory area is most likely affected by his tumor?

A. Lateral olfactory area

B. Hypothalamus

C. Septal nuclei

D. Prefrontal cortex