Social Science / Psychology
PSYC 388 - Final Exam Questions with
Verified Correct Answers 2026| Already
Graded A+
QUESTIONS ANSWERS
What is the temporal relationship They share a cyclical & feedback loop relationship which
between per gene expression and PER involves the per gene expression producing mRNA
protein levels in fruit flies? In translated into a PER protein
mammals?
In fruit flies, on what clock gene or Light affects the CRY protein to produce phase shifts and
protein does light act to cause phase bind to TIM to cause degradation & reset the clock
shifts, and how does light affect that gene
or protein?
In mice, on what clock gene or protein The light increases PER 1 & 2 gene expressions to produce a
does light act to cause phase shifts, and phase shift
how does light affect that gene or
protein?
Can circadian clocks operate without Yes, and specific prokaryotes and eukaryotes are
gene transcription, and if so, what is supporting evidence
the evidence?
The circadian clock is said to be 'cell Cell Autonomous refers to clock rhythms have their own
autonomous' - what does that mean, clock, hence can independently oscillate
and what is the evidence?
,Are there circadian clocks in peripheral Peripheral organs and tissues have clocks entrained by
organs and tissues (e.g., liver, pancreas, local stimuli and synchronized by the SCN master
etc) and if so, what stimuli are they clock
entrained by, and what role does the
SCN pacemaker play?
Why do circadian activity rhythms damp Multiple weeks of constant light exposure disrupts
out in nocturnal rodents maintained in circadian rhythms leading to desynchronization in the
constant light for many weeks? SCN
What effect does constant light have on
individual circadian clock cells in the
SCN?
In mice, what effect does Per protein The PER protein influences Bmal1's ability to activate the
have on Bmal1? Does it affect Bmal1 per & cry genes to regulate the circadian rhythms
gene expression, or does it affect how
Bmal1 protein activates the per and
cry genes?
If the SCN pacemaker is made up of The circadian activity rhythms would be weakened and
several thousand individual circadian disrupted
clock cells, what happens to
circadian activity rhythms if those cells
become desynchronized from each
other?
Following a shift of the LD cycle, do Different brain and organ may have their own clocks
circadian clocks in different brain and which re-entrain at different rates, while others are
body parts re-entrain at the same rate controlled by the master SCN
or at different rates?
What role do rods and cones play in Rods and cons contribute to the clock's response to
entrainment of the circadian clock by different light wavelengths and intensities.
light in mammals? Are they necessary (no
, entertainment without rods and They are not always necessary or sufficient for
cones)? Are they entrainment as many organisms can respond to light-
sufficient (entrainment is possible with dark cycles without them
only rods and cones)?
What role does the photopigment Melanopsin detects and sends light signals to the SCN. It
melanopsin play in is necessary and but insufficient as factors like rods &
entrainment of the circadian clock by
cons also contribute to this process
light in mammals? Is it necessary? Is it
sufficient?
What cells in the retina contain Intrinsically photosensitive retinal ganglion cells (IPRGCs)
melanopsin? contain melanopsin
What are 'intrinsically photoreceptive Specialized retinal ganglion cells that have their own light-
retinal ganglion cells' (IPRGCs) and sensitive pigment.
what is their relationship with rods
Although they are different from the rods & cones,
and cones?
IPRGCs still receive inputs from them
Which wavelength (and associated Blue light is the most effective for inducing phase shifts
colour) of light is most effective for because rhythms have photoreceptors that are most
inducing phase shifts? sensitive to blue light
Knockout of the gene Bmal1 has what Causes arrhythmicity
effect on circadian rhythms in mice?
PSYC 388 - Final Exam Questions with
Verified Correct Answers 2026| Already
Graded A+
QUESTIONS ANSWERS
What is the temporal relationship They share a cyclical & feedback loop relationship which
between per gene expression and PER involves the per gene expression producing mRNA
protein levels in fruit flies? In translated into a PER protein
mammals?
In fruit flies, on what clock gene or Light affects the CRY protein to produce phase shifts and
protein does light act to cause phase bind to TIM to cause degradation & reset the clock
shifts, and how does light affect that gene
or protein?
In mice, on what clock gene or protein The light increases PER 1 & 2 gene expressions to produce a
does light act to cause phase shifts, and phase shift
how does light affect that gene or
protein?
Can circadian clocks operate without Yes, and specific prokaryotes and eukaryotes are
gene transcription, and if so, what is supporting evidence
the evidence?
The circadian clock is said to be 'cell Cell Autonomous refers to clock rhythms have their own
autonomous' - what does that mean, clock, hence can independently oscillate
and what is the evidence?
,Are there circadian clocks in peripheral Peripheral organs and tissues have clocks entrained by
organs and tissues (e.g., liver, pancreas, local stimuli and synchronized by the SCN master
etc) and if so, what stimuli are they clock
entrained by, and what role does the
SCN pacemaker play?
Why do circadian activity rhythms damp Multiple weeks of constant light exposure disrupts
out in nocturnal rodents maintained in circadian rhythms leading to desynchronization in the
constant light for many weeks? SCN
What effect does constant light have on
individual circadian clock cells in the
SCN?
In mice, what effect does Per protein The PER protein influences Bmal1's ability to activate the
have on Bmal1? Does it affect Bmal1 per & cry genes to regulate the circadian rhythms
gene expression, or does it affect how
Bmal1 protein activates the per and
cry genes?
If the SCN pacemaker is made up of The circadian activity rhythms would be weakened and
several thousand individual circadian disrupted
clock cells, what happens to
circadian activity rhythms if those cells
become desynchronized from each
other?
Following a shift of the LD cycle, do Different brain and organ may have their own clocks
circadian clocks in different brain and which re-entrain at different rates, while others are
body parts re-entrain at the same rate controlled by the master SCN
or at different rates?
What role do rods and cones play in Rods and cons contribute to the clock's response to
entrainment of the circadian clock by different light wavelengths and intensities.
light in mammals? Are they necessary (no
, entertainment without rods and They are not always necessary or sufficient for
cones)? Are they entrainment as many organisms can respond to light-
sufficient (entrainment is possible with dark cycles without them
only rods and cones)?
What role does the photopigment Melanopsin detects and sends light signals to the SCN. It
melanopsin play in is necessary and but insufficient as factors like rods &
entrainment of the circadian clock by
cons also contribute to this process
light in mammals? Is it necessary? Is it
sufficient?
What cells in the retina contain Intrinsically photosensitive retinal ganglion cells (IPRGCs)
melanopsin? contain melanopsin
What are 'intrinsically photoreceptive Specialized retinal ganglion cells that have their own light-
retinal ganglion cells' (IPRGCs) and sensitive pigment.
what is their relationship with rods
Although they are different from the rods & cones,
and cones?
IPRGCs still receive inputs from them
Which wavelength (and associated Blue light is the most effective for inducing phase shifts
colour) of light is most effective for because rhythms have photoreceptors that are most
inducing phase shifts? sensitive to blue light
Knockout of the gene Bmal1 has what Causes arrhythmicity
effect on circadian rhythms in mice?
