BIOL251 / BIOL 251 Module & Lab 8 Practice Exam: Human
Anatomy & Physiology I with Lab UP-TO-DATE 2026 EXAM
Latest PDF Update)
SECTION A: VISION (THE EYE)
Multiple Choice Questions
Question 1
Which of the following is the correct order of structures that light passes through as it
enters the eye?
A) Lens → pupil → cornea → retina
B) Cornea → lens → pupil → retina
C) Cornea → pupil → lens → retina
D) Pupil → cornea → lens → retina
Correct Answer: C) Cornea → pupil → lens → retina
Rationale: Light enters the eye sequentially through the cornea (first refractive
surface), passes through the pupil (regulated by the iris), is further focused by the lens,
and finally reaches the retina (neural layer containing photoreceptors).
Question 2
The gel-like substance that fills the posterior cavity of the eye is the:
A) Aqueous humor
B) Vitreous humor
C) Hyaloid fluid
D) Choroid gel
Correct Answer: B) Vitreous humor
,Rationale: The posterior cavity of the eye is filled with vitreous humor, a clear gel that
helps maintain the shape of the eyeball. Aqueous humor fills the anterior chamber of
the eye.
Question 3
Which of the following structures of the eye is avascular and responsible for the initial
refraction of light?
A) Sclera
B) Choroid
C) Cornea
D) Iris
Correct Answer: C) Cornea
Rationale: The cornea is transparent, avascular, and serves as the primary refractive
surface of the eye, responsible for approximately 80% of light refraction. The sclera is
the tough, white protective outer layer.
Question 4
Which part of the eye controls the amount of light entering the eye?
A) Retina
B) Cornea
C) Iris
D) Optic nerve
Correct Answer: C) Iris
Rationale: The iris regulates the diameter of the pupil, controlling the amount of light
that enters the eye. The retina contains photoreceptors; the cornea refracts light.
,Question 5
Which photoreceptor cells are most active in dim lighting and are responsible for night
vision?
A) Cones
B) Rods
C) Bipolar cells
D) Ganglion cells
Correct Answer: B) Rods
Rationale: Rods are photoreceptors specialized for low-light (night) vision and do not
detect color. Cones are responsible for color vision and bright light conditions.
Question 6
Which part of the retina provides the sharpest vision?
A) Optic disc
B) Macula lutea
C) Fovea centralis
D) Peripheral retina
Correct Answer: C) Fovea centralis
Rationale: The fovea centralis is a tiny pit in the macula lutea containing only cones,
tightly packed. Each cone has a nearly 1:1 connection to bipolar cells, allowing for the
highest resolution and sharpest vision.
Question 7
The optic nerve (CN II) carries impulses from the retina to the:
A) Thalamus
B) Brain
C) Spinal cord
D) Hypothalamus
, Correct Answer: B) Brain
Rationale: The optic nerve is a sensory nerve that transmits visual information from
the retina to the brain (specifically to the visual cortex via the thalamus).
Question 8
A blockage in the canal of Schlemm would most likely lead to which condition?
A) Cataracts
B) Glaucoma
C) Macular degeneration
D) Retinal detachment
Correct Answer: B) Glaucoma
Rationale: The canal of Schlemm drains aqueous humor from the anterior chamber. A
blockage results in increased intraocular pressure (glaucoma), which can damage the
optic nerve.
Question 9
What is another term for nearsightedness?
A) Hyperopia
B) Myopia
C) Presbyopia
D) Astigmatism
Correct Answer: B) Myopia
Rationale: Myopia, or nearsightedness, is a refractive error where close objects are
seen clearly but distant objects appear blurry. Hyperopia is farsightedness, presbyopia is
age-related loss of accommodation, and astigmatism is irregular curvature of the cornea
or lens.
Anatomy & Physiology I with Lab UP-TO-DATE 2026 EXAM
Latest PDF Update)
SECTION A: VISION (THE EYE)
Multiple Choice Questions
Question 1
Which of the following is the correct order of structures that light passes through as it
enters the eye?
A) Lens → pupil → cornea → retina
B) Cornea → lens → pupil → retina
C) Cornea → pupil → lens → retina
D) Pupil → cornea → lens → retina
Correct Answer: C) Cornea → pupil → lens → retina
Rationale: Light enters the eye sequentially through the cornea (first refractive
surface), passes through the pupil (regulated by the iris), is further focused by the lens,
and finally reaches the retina (neural layer containing photoreceptors).
Question 2
The gel-like substance that fills the posterior cavity of the eye is the:
A) Aqueous humor
B) Vitreous humor
C) Hyaloid fluid
D) Choroid gel
Correct Answer: B) Vitreous humor
,Rationale: The posterior cavity of the eye is filled with vitreous humor, a clear gel that
helps maintain the shape of the eyeball. Aqueous humor fills the anterior chamber of
the eye.
Question 3
Which of the following structures of the eye is avascular and responsible for the initial
refraction of light?
A) Sclera
B) Choroid
C) Cornea
D) Iris
Correct Answer: C) Cornea
Rationale: The cornea is transparent, avascular, and serves as the primary refractive
surface of the eye, responsible for approximately 80% of light refraction. The sclera is
the tough, white protective outer layer.
Question 4
Which part of the eye controls the amount of light entering the eye?
A) Retina
B) Cornea
C) Iris
D) Optic nerve
Correct Answer: C) Iris
Rationale: The iris regulates the diameter of the pupil, controlling the amount of light
that enters the eye. The retina contains photoreceptors; the cornea refracts light.
,Question 5
Which photoreceptor cells are most active in dim lighting and are responsible for night
vision?
A) Cones
B) Rods
C) Bipolar cells
D) Ganglion cells
Correct Answer: B) Rods
Rationale: Rods are photoreceptors specialized for low-light (night) vision and do not
detect color. Cones are responsible for color vision and bright light conditions.
Question 6
Which part of the retina provides the sharpest vision?
A) Optic disc
B) Macula lutea
C) Fovea centralis
D) Peripheral retina
Correct Answer: C) Fovea centralis
Rationale: The fovea centralis is a tiny pit in the macula lutea containing only cones,
tightly packed. Each cone has a nearly 1:1 connection to bipolar cells, allowing for the
highest resolution and sharpest vision.
Question 7
The optic nerve (CN II) carries impulses from the retina to the:
A) Thalamus
B) Brain
C) Spinal cord
D) Hypothalamus
, Correct Answer: B) Brain
Rationale: The optic nerve is a sensory nerve that transmits visual information from
the retina to the brain (specifically to the visual cortex via the thalamus).
Question 8
A blockage in the canal of Schlemm would most likely lead to which condition?
A) Cataracts
B) Glaucoma
C) Macular degeneration
D) Retinal detachment
Correct Answer: B) Glaucoma
Rationale: The canal of Schlemm drains aqueous humor from the anterior chamber. A
blockage results in increased intraocular pressure (glaucoma), which can damage the
optic nerve.
Question 9
What is another term for nearsightedness?
A) Hyperopia
B) Myopia
C) Presbyopia
D) Astigmatism
Correct Answer: B) Myopia
Rationale: Myopia, or nearsightedness, is a refractive error where close objects are
seen clearly but distant objects appear blurry. Hyperopia is farsightedness, presbyopia is
age-related loss of accommodation, and astigmatism is irregular curvature of the cornea
or lens.
