CBNS PRACTICE EXAM 2025/2026
QUESTIONS AND ANSWERS 100% PASS
Which layer of retinal neurons has axons that leave the retina?
a. Outer Nuclear layer
b. Inner Nuclear layer
c. Ganglion cell layer
d. Inner plexiform layer - ANS C. Ganglion cell layer
The ganglion cell layer contains the cell bodies of the ganglion cells. These are the only cells
with axons that leave the retina
What is the spectral sensitivity of the free cone pigments?
a. 460 nm
b. 560 nm
c. 430 nm
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, d. 530 nm - ANS d. 530 nm
The cones in our retinas contain one of three opsins. These opsins give the photopigments
different spectral sensitivities. Green cones are maximally activated by the light with a
wavelength of about 530 nm.
What is reflection? - ANS c. Light rays bouncing off a surface
Why is the retina said to be duplex? - ANS Because it can work under both scotopic and
photopic lighting conditions
Why do we say that ganglion cells are mainly responsive to differences in illumination that
occur within their receptive fields? - ANS Center surround ganglion cells respond best when
a light or dark edge falls at the boundary between the center and surround regions of the
receptive field
Distinguish the responses of M type and P type retinal ganglion cells to stimulation of their
receptive field centers - ANS M cells respond with a transient burst of action potentials and P
cells respond with a sustained discharge.
What is the role of the pupil in vision?
a. carries axons from the retina
b. Protects the transparent surface of the eye
c. Provides color to the eye
d. Allows light to enter the eye and reach the retina. - ANS D.
Which retinal neurons fire action potentials?
pg. 2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
QUESTIONS AND ANSWERS 100% PASS
Which layer of retinal neurons has axons that leave the retina?
a. Outer Nuclear layer
b. Inner Nuclear layer
c. Ganglion cell layer
d. Inner plexiform layer - ANS C. Ganglion cell layer
The ganglion cell layer contains the cell bodies of the ganglion cells. These are the only cells
with axons that leave the retina
What is the spectral sensitivity of the free cone pigments?
a. 460 nm
b. 560 nm
c. 430 nm
pg. 1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
, d. 530 nm - ANS d. 530 nm
The cones in our retinas contain one of three opsins. These opsins give the photopigments
different spectral sensitivities. Green cones are maximally activated by the light with a
wavelength of about 530 nm.
What is reflection? - ANS c. Light rays bouncing off a surface
Why is the retina said to be duplex? - ANS Because it can work under both scotopic and
photopic lighting conditions
Why do we say that ganglion cells are mainly responsive to differences in illumination that
occur within their receptive fields? - ANS Center surround ganglion cells respond best when
a light or dark edge falls at the boundary between the center and surround regions of the
receptive field
Distinguish the responses of M type and P type retinal ganglion cells to stimulation of their
receptive field centers - ANS M cells respond with a transient burst of action potentials and P
cells respond with a sustained discharge.
What is the role of the pupil in vision?
a. carries axons from the retina
b. Protects the transparent surface of the eye
c. Provides color to the eye
d. Allows light to enter the eye and reach the retina. - ANS D.
Which retinal neurons fire action potentials?
pg. 2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
