BIOL 223A EXAM 4 QUESTIONS AND
ANSWERS. VERIFIED 2026/2027.
Olfactory sensory neurons are short-lived and, therefore, replaced frequently. How does this
turnover happen?
A. mitotic division and differentiation of odorants
B. mitotic division and differentiation of basal epithelial cells
C. mitotic division of olfactory sensory neurons
D. mitotic division and differentiation of supporting cells - ANS B. mitotic division and
differentiation of basal epithelial cells
When the tympanic membrane vibrates with the same frequency as the incoming sound waves
it is known as:
A. amplitude.
B. resonance.
C. cycles.
D. hertz.
E. pitch. - ANS B. resonance
*the right combination of frequencies and amplitudes including the tympanic membrane will
begin to vibrate at the same frequency as the sound = RESONANCE
The taste sensation that is triggered by the amino acid glutamate is known as:
1 @2026 COPY ALLRIGHTS RESERVED.
,A. peppery.
B. salty.
C. sweet.
D. sour.
E. umami - ANS E. umami
A person with damage to this part of the brain (indicated by the arrow) will have normal
acoustic reflexes but will have difficulty performing which of the following functions?
A. interpreting sounds and recognizing a pattern in them
B. directing input from the thalamus to the brainstem
C. sending auditory information to the midbrain
D. directing a variety of motor reflexes to sound - ANS A. interpreting sounds and recognizing
a pattern in them
Which of these is NOT a type of photoreceptor?
A. red cone
B. blue cone
C. green cone
D. yellow cone - ANS D. yellow cone
The following steps occur in rods when they are excited by photons of light. What is the proper
sequence for these steps?
1. Membrane sodium channels close.
2. Increased phosphodiesterase breaks down cGMP.
2 @2026 COPY ALLRIGHTS RESERVED.
, 3. Retinal changes from the 11-cis form to the 11-trans form.
4. The membrane hyperpolarizes and the rate of neurotransmitter release declines.
5. Opsin activates transducin.
6. Opsin activation occurs.
A. 6, 3, 5, 2, 1, 4
B. 3, 6, 5, 2, 1, 4
C. 1, 6, 5, 2, 4, 3
D. 1, 3, 4, 5, 6, 2
E. 3, 6, 5, 1, 2, 4 - ANS B. 3, 6, 5, 2, 1, 4
In order:
1. retinal changes from the 11-cis form to 11-trans form
2. Opsin activation occurs
3. Opsin activates transducin
4. increased phosphodiesterase breaks down cGMP
5. Membrane sodium channels close
6. The membrane hyperpolarizes and the rate of neurotransmitter release declines
Which of the following is not one of the six primary taste sensations?
A. umami
B. salty
C. sour
D. peppery
E. sweet - ANS D. peppery
3 @2026 COPY ALLRIGHTS RESERVED.
ANSWERS. VERIFIED 2026/2027.
Olfactory sensory neurons are short-lived and, therefore, replaced frequently. How does this
turnover happen?
A. mitotic division and differentiation of odorants
B. mitotic division and differentiation of basal epithelial cells
C. mitotic division of olfactory sensory neurons
D. mitotic division and differentiation of supporting cells - ANS B. mitotic division and
differentiation of basal epithelial cells
When the tympanic membrane vibrates with the same frequency as the incoming sound waves
it is known as:
A. amplitude.
B. resonance.
C. cycles.
D. hertz.
E. pitch. - ANS B. resonance
*the right combination of frequencies and amplitudes including the tympanic membrane will
begin to vibrate at the same frequency as the sound = RESONANCE
The taste sensation that is triggered by the amino acid glutamate is known as:
1 @2026 COPY ALLRIGHTS RESERVED.
,A. peppery.
B. salty.
C. sweet.
D. sour.
E. umami - ANS E. umami
A person with damage to this part of the brain (indicated by the arrow) will have normal
acoustic reflexes but will have difficulty performing which of the following functions?
A. interpreting sounds and recognizing a pattern in them
B. directing input from the thalamus to the brainstem
C. sending auditory information to the midbrain
D. directing a variety of motor reflexes to sound - ANS A. interpreting sounds and recognizing
a pattern in them
Which of these is NOT a type of photoreceptor?
A. red cone
B. blue cone
C. green cone
D. yellow cone - ANS D. yellow cone
The following steps occur in rods when they are excited by photons of light. What is the proper
sequence for these steps?
1. Membrane sodium channels close.
2. Increased phosphodiesterase breaks down cGMP.
2 @2026 COPY ALLRIGHTS RESERVED.
, 3. Retinal changes from the 11-cis form to the 11-trans form.
4. The membrane hyperpolarizes and the rate of neurotransmitter release declines.
5. Opsin activates transducin.
6. Opsin activation occurs.
A. 6, 3, 5, 2, 1, 4
B. 3, 6, 5, 2, 1, 4
C. 1, 6, 5, 2, 4, 3
D. 1, 3, 4, 5, 6, 2
E. 3, 6, 5, 1, 2, 4 - ANS B. 3, 6, 5, 2, 1, 4
In order:
1. retinal changes from the 11-cis form to 11-trans form
2. Opsin activation occurs
3. Opsin activates transducin
4. increased phosphodiesterase breaks down cGMP
5. Membrane sodium channels close
6. The membrane hyperpolarizes and the rate of neurotransmitter release declines
Which of the following is not one of the six primary taste sensations?
A. umami
B. salty
C. sour
D. peppery
E. sweet - ANS D. peppery
3 @2026 COPY ALLRIGHTS RESERVED.
