Eye don’t see nothing wrong
A) Lens opacity
B) Increased intraocular pressure
C) Retinal detachment
D) Weakness of extraocular muscles
Increased intraocular pressure
Which type of chemical must a substance be in order to be detected as an odor?
A) Hydrophilic
B) Lipophilic
C) Volatile
D) Ionic
Volatile
(For a substance to be detected as an odor, its molecules must easily evaporate and enter the gas phase at room temperature. This volatility allows the molecules to become airborne and enter the nasal cavity during inhalation, where they can reach the olfactory receptors)
Which taste is primarily triggered by sodium ions (Na⁺)?
A. Bitter
B. Sour
C. Sweet
D. Salty
Salty
Which structure first collects sound waves from the environment?
A. Cochlea
B. Tympanic membrane
C. Pinna (Auricle)
D. Staples
Pinna (Auricle)
Which type of receptor detects light touch on the skin?
A. Thermoreceptors
B. Mechanoreceptors
C. Nociceptors
D. Chemoreceptors
Mechanoreceptors
Which complex of the electron transport chain receives electrons directly from NADH?
A) Complex I
B) Complex II
C) Complex III
D) Complex IV
Complex I
Complex I: directly accepts high-energy electrons from NADH, oxidizing it back into NAD+.
Which ocular structure is primarily damaged over time due to untreated glaucoma?
A) Retina
B) Optic nerve
C) Cornea
D) Iris
Optic nerve
Where are the receptor proteins for smell located?
A) Supporting cells
B) Olfactory cilia (hairs) of sensory neurons
C) Cribriform plate
D) Olfactory bulb glomeruli
Olfactory cilia (hairs) of sensory neurons
(The specialized G-protein coupled receptor proteins that physically bind to odorant molecules are located directly on the membranes of the olfactory cilia. These tiny, hair-like extensions project from the dendrite of the olfactory sensory neurons into the thick layer of mucus lining the nasal cavity, capturing airborne chemicals as you breathe.)
Which taste is a warning sign for spoiled or unripe food?
A. Sour
B. Umami
C. Sweet
D. Bitter
Sour
Which unit is used to measure the loudness (amplitude) of sound?
A) Hz
B) dB
C) W
D) J
dB
(Decibels)
Cold thermoreceptors are most active in which temperature range?
A. 32°F–50°F
B. 50°F–104°F
C. 90°F–118°F
D. Above 118°F
50°F–104°F
(Cutaneous cold thermoreceptors respond to innocuous (harmless) cooling and are physiologically active within a broad window between 10°C and 40°C (50°F to 104°F).)
Which complex of the ETC does not pump protons across the mitochondrial membrane?
A) Complex I
B) Complex II
C) Complex III
D) Complex IV
Complex II
(Complex II is the only protein complex in the electron transport chain (ETC) that does not pump protons H+ across the inner mitochondrial membrane.)
Which two structures make up the fibrous tunic of the eye?
A) Iris and ciliary body
B) Retina and macula
C) Sclera and cornea
D) Choroid and lens
Sclera and cornea
(The outermost layer is the fibrous tunic, which provides structural support. It consists entirely of:
How often are olfactory sensory neurons typically replaced in adults?
A) Every 5–7 days
B) Every 15–30 days
C) Every 30–60 days
D) They do not regenerate
Every 30–60 days
(This is one of the very few places in the entire human body where neurogenesis (the growth and development of new nervous tissue) regularly occurs in adults.)
Before a chemical can be tasted, it must first:
A. Be digested in the stomach
B. Be chewed for 30 seconds
C. Dissolve in saliva
D. Travel to the thalamus
Dissolve in saliva
Which auditory ossicle is directly connected to the tympanic membrane?
A) Incus
B) Stapes
C) Malleus
D) Cochlea
Malleus
Free nerve endings are responsible for detecting:
A. Vibration only
B. Light touch only
C. Pain, extreme temperatures, and chemical irritation
D. Muscle stretch and joint position
Pain, extreme temperatures, and chemical irritation
The final electron acceptor in the electron transport chain is:
A) Water
B) NAD⁺
C) Oxygen
D) Cytochrome c
Oxygen
(Molecular oxygen O2 serves as the terminal or final electron acceptor at the very end of the electron transport chain.)
The _____ provides vital nourishment and regulates temperature for the outer retina:
A) Choroid
B) Lens
C) Macula
D) Cornea
Choroid
(The choroid is the highly vascular, middle layer of the eye situated between the sclera and the retina. It contains a dense network of blood vessels that provides oxygen and vital nutrients to the avascular outer retina.)
Which cranial nerve carries the sense of smell?
A) CN I
B) CN II
C) CN V
D) CN VII
CN I
(Olfactory)
Which cranial nerve carries taste sensations from the anterior 2/3 of the tongue?
CN VII (Facial)
What is the role of the Eustachian tube?
A) Amplifies sound waves
B) Converts mechanical energy to electrical signals
C) Equalizes pressure across the tympanic membrane
D) Produces earwax
Equalizes pressure across the tympanic membrane
Which brain structure initially receives all touch sensory input for sorting?
A. Cerebellum
B. Thalamus
C. Hippocampus
D. Amygdala
Thalamus
(The thalamus functions as the central relay station and sorting center of the brain for almost all sensory systems.)
How many protons are pumped by Complex I per NADH oxidized?
A) 2
B) 3
C) 4
D) 6
4
(For every single molecule of NADH oxidized at Complex I (NADH dehydrogenase), exactly 4 protons H+ are actively translocated (pumped) from the mitochondrial matrix across the inner mitochondrial membrane and into the intermembrane space.)
What is the primary function of rods versus cones in the retina?
A) Rods detect color; cones detect dim light
B) Rods detect bright light; cones detect peripheral vision
C) Rods detect dim light; cones detect color
D) Rods detect near vision; cones detect far vision
Rods detect dim light; cones detect color.
Which brain structure does the olfactory pathway bypass that all other sensory pathways normally pass through first?
A) Hypothalamus
B) Amygdala
C) Thalamus
D) Hippocampus
Thalamus
(Olfaction (smell) bypasses the thalamus entirely on its initial journey, projecting nerve signals directly from the olfactory bulb to the primary olfactory cortex.)
All taste fibers from CN VII, IX, and X converge in which brainstem structure?
A. Thalamus
B. Solitary nucleus in the medulla
C. Cerebellum
D. Primary gustatory cortex
Solitary nucleus in the medulla
Which part of the inner ear is primarily responsible for hearing?
A) Semicircular canals
B) Vestibule
C) Cochlea
D) Utricle
Cochlea
A patient can feel touch on the face and neck but has zero sensation from the nipples down. Which spinal level is most likely injured?
A. T2
B. T4
C. T6
D. T10
T4
Which complex of the ETC directly reduces oxygen to water?
A) Complex I
B) Complex II
C) Complex III
D) Complex IV
Complex IV
It transfers four electrons to an oxygen molecule, combining them with four protons from the mitochondrial matrix to directly reduce oxygen into two molecules of water.
How does accommodation work for near objects?
A) Ciliary muscles relax, flattening the lens
B) Ciliary muscles contract, rounding the lens
C) Pupils dilate, reducing lens refraction
D) Pupils constrict, flattening the lens
Ciliary muscles contract, rounding the lens
A patient reports smelling burning rubber before a temporal lobe seizure. This phenomenon is best described as:
Phantosmia
(phantom smell)
Which taste is triggered by amino acids like glutamate?
A. Bitter
B. Sour
C. Umami
D. Salty
Umami
Which structure contains the hair cells that convert fluid movements into electrical signals?
A) Organ of Corti
B) Cupula
C) Otoliths
D) Saccule
Organ of Corti
Which term describes the brain misinterpreting visceral pain as originating from the skin?
A. Neuropathy
B. Proprioception
C. Referred pain
D. Hyperalgesia
Referred pain
What is the primary purpose of electron movement through the ETC?
A) Generate NADH
B) Pump protons to create a gradient
C) Produce CO₂ directly
D) Transport glucose
Pump protons to create a gradient
(The protein complexes (I, III, and IV) capture this released free energy and use it like mechanical pumps to translocate protons H+ from the matrix into the intermembrane space.)
How does accommodation work for distant objects?
A) Ciliary muscles relax, flattening the lens
B) Ciliary muscles contract, rounding the lens
C) Pupils dilate, reducing lens refraction
D) Pupils constrict, flattening the lens
Ciliary muscles relax, flattening the lens
Which of the following is the most likely consequence of shearing olfactory neurons at the cribriform plate following a head trauma?
Permanent anosmia
A medullary stroke could cause:
A. Loss of taste on the anterior tongue only
B. Loss of taste on the posterior tongue only
C. Loss of taste across the entire mouth
D. Hyper-sensitivity to sweet tastes
Loss of taste across the entire mouth. (Ageusia)
What is the correct sequence of energy transfer for hearing?
A) Fluid → Air → Bone
B) Air → Bone → Fluid → Hair cells
C) Bone → Fluid → Air
D) Air → Fluid → Bone
Air → Bone → Fluid → Hair cells
Diabetic neuropathy commonly presents first with loss of sensation in:
A. Chest and face
B. Hands and feet
C. Abdomen and back
D. Shoulders and arms
Hands and feet
The proton-motive force is used to:
A) Pump more protons into the matrix
B) Rotate ATP synthase and make ATP
C) Oxidize NADH
D) Increase oxygen solubility
Rotate ATP synthase and make ATP
(This flow of protons drives the mechanical, physical rotation of the enzyme’s central stalk and c-ring (the binding change mechanism), providing the kinetic energy needed to phosphorylate ADP and inorganic phosphate into ATP.)
Fill in the blanks: As light enters the eye, it passes sequentially through the cornea, the [A] humor, the pupil, the lens, the [B] humor, and finally strikes the retina.
A) Aqueous; Vitreous
B) Vitreous; Aqueous
C) Synovial; Vitreous
D) Vitreous; Synovial
Aqueous; Vitreous
A paramedic enters a house with a hydrogen sulfide leak. Initially, the smell is overwhelming, but after 10 minutes, they no longer notice it. This is known as:
Olfactory fatigue
Which best explains why bitter tastes can trigger gagging before conscious recognition?
A. Bitter receptors are located only in the cerebellum
B. Taste impulses first activate autonomic reflex centers in the medulla
C. Bitter taste does not require cranial nerve signaling
D. The thalamus bypasses the medulla
Taste impulses first activate autonomic reflex centers in the medulla.
A ruptured tympanic membrane primarily results in which type of hearing loss?
A) Sensorineural
B) Conductive
C) Central auditory
D) Mixed
Conductive
Why does referred pain from a heart attack often radiate down the left arm?
A. The vagus nerve innervates the arm
B. Shared spinal cord pathways (T1–T5 dermatomes) misinterpret origin
C. Coronary arteries supply the arm
D. Pain signals bypass the spinal cord
Shared spinal cord pathways (T1–T5 dermatomes) misinterpret origin
Which best describes the mnemonic OIL RIG in redox reactions?
A) Oxidation is loss, reduction is gain
B) Oxygen is low, respiration is good
C) Organisms in light require glycolysis
D) Only ions leave rapidly in gradients
Oxidation is loss, reduction is gain
(Oxidation is loss, reduction is gain: The mnemonic OIL RIG is a universally taught memory tool in chemistry and biochemistry to keep the direction of electron transfer clear during reduction-oxidation (redox) reactions.)
What is a hyphema, and how should the patient be positioned during transport?
A) Blood in the posterior chamber; lay flat
B) Blood in the anterior chamber; head elevated 30–45°
C) Swelling of the retina; sitting upright
D) Corneal clouding; prone position
Blood in the anterior chamber; head elevated 30–45°
Which of the following complications can result from a fracture of the cribriform plate with CSF rhinorrhea?
Meningitis
(Creates a pathway from the pathogen filled nose to the sterile The correct spelling is cerebrovascular..
After taste signals synapse in the solitary nucleus, where do they travel next for conscious perception?
A. Cerebellum
B. Thalamus
C. Hypothalamus
D. Corpus callosum
Thalamus
Which vestibular structure detects vertical acceleration, such as riding in an elevator?
A) Utricle
B) Saccule
C) Cochlea
D) Incus
Saccule
(The saccule detects vertical movement (up and down), while the utricle detects horizontal movement (forward and backward)
A trauma patient loses pain sensation in the right leg but retains vibration sense. Which side of the spinal cord is injured?
A. Left
B. Right
C. Both
D. Neither
Left
(Nerves in the legs that sense pain and temperature cross over at the spine.)
What happens to NAD⁺ availability if the ETC is completely blocked?
A) It increases
B) It decreases
C) It stays the same
D) It converts to FAD
It decreases
(NADH builds up inside the mitochondria because it has nowhere to dump its electrons, causing the available pool of NAD⁺ to drop drastically.)
Why is vomiting dangerous for a patient with an open globe injury?
A) It spreads infection to the orbit
B) It increases intraocular pressure and may extrude eye contents
C) It causes dehydration that affects the retina
D) It constricts the pupils and reduces vision
It increases intraocular pressure and may extrude eye contents
Which of the following best explains why odors can trigger emotional responses before conscious recognition?
Olfactory tracts connect directly to the limbic system
Which statement is correct regarding central vs. peripheral taste deficits?
A. Peripheral nerve damage causes complete loss of taste across the mouth
B. Central medullary damage can cause widespread taste loss
C. Medullary injuries do not affect taste
D. Damage to the thalamus only affects sweet perception
Central medullary damage can cause widespread taste loss
Which condition is characterized by episodes of vertigo, tinnitus, and fluctuating hearing loss?
A) Motion sickness
B) Ménière’s disease
C) BPPV
D) Ototoxicity
Ménière’s disease
(This condition involves an overaccumulation of fluid (endolymph) inside the saccule and scala media, leading to severe vertigo, tinnitus, and hearing loss.)
A patient exposed to 45°F water initially feels cold, but soon develops pain. Why?
A. Thermoreceptors adapt to low frequency vibration
B. Mechanoreceptors replace thermal sensation
C. Cold thermoreceptors stop firing and nociceptors(pain) activate
D. Warm thermoreceptors trigger pain perception
Cold thermoreceptors stop firing and nociceptors activate
This is responsible for the ‘painful cold’ feelings.
Which class of cells rely entirely on anaerobic glycolysis due to lack of mitochondria?
A) Skeletal muscle
B) Red blood cells
C) Neurons
D) Hepatocytes
Red blood cells
(They rely 100% on anaerobic glycolysis in the cytoplasm to generate their ATP, reducing pyruvate into lactic acid to regenerate the necessary NAD⁺.)
Which orbital bone is most commonly fractured in a blowout fracture, and what muscle can become entrapped?
A) Frontal bone; Superior oblique
B) Maxillary bone; Inferior rectus
C) Ethmoid bone; Lateral rectus
D) Zygomatic bone; Superior rectus
Maxillary bone; Inferior rectus
A patient with sudden anosmia after a motor vehicle collision also has a clear nasal discharge that tests positive for glucose. The most likely site of injury is:
A) Sphenoid sinus
B) Cribriform plate of the ethmoid bone
C) Maxillary sinus wall
D) Nasal septum cartilage
Cribriform plate of the ethmoid bone
(High-impact injury like a motor vehicle collision can fracture this fragile bone.)
What cranial nerves comprise the gustatory system?
CN VII, IX, X.
Which mechanism best explains why cool water entering the middle ear can cause vertigo?
A) Increased cochlear fluid pressure
B) Direct stimulation of the auditory nerve
C) Temperature-induced endolymph movement simulating head rotation
D) Blockage of the Eustachian tube
Temperature-induced endolymph movement simulating head rotation.
Which type of sensory loss pattern is characteristic of diabetic neuropathy?
A. Proximal muscle weakness first
B. Loss of proprioception in the trunk
C. Glove-and-stocking distribution of numbness
D. Isolated facial sensory loss
Glove-and-stocking distribution of numbness
(Destroys the longest nerves in the feet and lower legs then moves on to the hands.)
In the presence of cyanide, oxygen is available but cells cannot use it. This is called:
A) Ischemic hypoxia
B) Histotoxic hypoxia
C) Anemic hypoxia
D) Hypovolemic hypoxia
Histotoxic hypoxia
(This specific type of hypoxia occurs when oxygen delivery to the tissues is completely normal, but the cells themselves are poisoned and cannot utilize the oxygen. Caused by cyanide poisoning.