PSYC 388 ACTUAL EXAM PAPER 2026
QUESTIONS WITH SOLUTIONS GRADED A+
◉ Period (tau) . Answer: - duration of a complete cycle
◉ Wavelength (lambda) . Answer: - distance between two acrophases
(peaks)
- distance a wave travels in one period, or length of one cycle
◉ Amplitude (2 definitions) . Answer: - the range (peak to trough) OR
- half the range (peak to mean/mesor)
◉ Acrophase . Answer: the peak of the curve (sine wave)
◉ What are the four 'circa' rhythms? (and give examples) . Answer: 1.
Circaannual (approx. 1 year)
Ex: summer and winter
2. Circalunar (approx 29.5 days)
Ex: determines how much light there is at night
3. Circadian (approx. 24hrs)
4. Circatidal (approx. 12.5 hrs)
,Ex: high and low tide
◉ What two characteristics distinguish these from
other rhythms? . Answer: 1. the duration of each cycle (its period),
matches a major geophysical cycle
2. the rhythms PERSIST in the absence of environmental cycles, with a
periodicity that only approximates the geophysical cycle
◉ How do you test experimentally whether a daily rest-activity rhythm
in an animal is
generated by an internal circadian clock, and not by environmental
cycles? . Answer: - keep the animal in constant conditions attempting to
remove all rhythmic stimuli
◉ Is the circadian rhythm depicted in this actogram free-running faster
or slower than
24h? . Answer: - staircase <<24hrs
- upside-down staircase >>24hrs
◉ What is meant by temperature compensation, and why is this a
necessary
characteristic of a circadian clock? . Answer: - rate of biochemical
reactions (basis of all biological processes) varies with temperature
- approx. doubles with each 10 degree centigrade increase
, - must be able to cycle with a stable, ciracadian period across a
potentially wide range of temperatures (clock, not thermometer)
- runs at same rate regardless of temperature
- biochemical reactions cannot violate the rate-temperature principle, so
for the clock to tell accurate time across a range of temperatures
(compensated)
Ex: as tissue temperature rises, clock mechanism speeds up but a second
mechanism slows down the clock mechanism --> as temperature rises,
the output from this inhibitory mechanism increases, counterbalancing
the increase in clock speed caused by the higher temperature (net result
that clock speed doesn't change with temperature --> maintained at a
stable speed)
◉ If a honey bee regularly finds food at a feeder at noon in a lab room in
Vancouver,
and is then rapidly flown to Montreal [3 time zones east], where the
feeder is set up in
an identical lab room, what time the next day (in Montreal time) will the
bee look for
food at the feeder? . Answer: - bee will look for food in the feeder at
3pm (3 hours after 12 in Montreal, but 12pm in Vancouver)
◉ Why should psychologists (scientists who study or treat behavior)
care about
circadian rhythms? Give 4 reasons. . Answer: 1. understanding
motivation: why organisms do what they do
QUESTIONS WITH SOLUTIONS GRADED A+
◉ Period (tau) . Answer: - duration of a complete cycle
◉ Wavelength (lambda) . Answer: - distance between two acrophases
(peaks)
- distance a wave travels in one period, or length of one cycle
◉ Amplitude (2 definitions) . Answer: - the range (peak to trough) OR
- half the range (peak to mean/mesor)
◉ Acrophase . Answer: the peak of the curve (sine wave)
◉ What are the four 'circa' rhythms? (and give examples) . Answer: 1.
Circaannual (approx. 1 year)
Ex: summer and winter
2. Circalunar (approx 29.5 days)
Ex: determines how much light there is at night
3. Circadian (approx. 24hrs)
4. Circatidal (approx. 12.5 hrs)
,Ex: high and low tide
◉ What two characteristics distinguish these from
other rhythms? . Answer: 1. the duration of each cycle (its period),
matches a major geophysical cycle
2. the rhythms PERSIST in the absence of environmental cycles, with a
periodicity that only approximates the geophysical cycle
◉ How do you test experimentally whether a daily rest-activity rhythm
in an animal is
generated by an internal circadian clock, and not by environmental
cycles? . Answer: - keep the animal in constant conditions attempting to
remove all rhythmic stimuli
◉ Is the circadian rhythm depicted in this actogram free-running faster
or slower than
24h? . Answer: - staircase <<24hrs
- upside-down staircase >>24hrs
◉ What is meant by temperature compensation, and why is this a
necessary
characteristic of a circadian clock? . Answer: - rate of biochemical
reactions (basis of all biological processes) varies with temperature
- approx. doubles with each 10 degree centigrade increase
, - must be able to cycle with a stable, ciracadian period across a
potentially wide range of temperatures (clock, not thermometer)
- runs at same rate regardless of temperature
- biochemical reactions cannot violate the rate-temperature principle, so
for the clock to tell accurate time across a range of temperatures
(compensated)
Ex: as tissue temperature rises, clock mechanism speeds up but a second
mechanism slows down the clock mechanism --> as temperature rises,
the output from this inhibitory mechanism increases, counterbalancing
the increase in clock speed caused by the higher temperature (net result
that clock speed doesn't change with temperature --> maintained at a
stable speed)
◉ If a honey bee regularly finds food at a feeder at noon in a lab room in
Vancouver,
and is then rapidly flown to Montreal [3 time zones east], where the
feeder is set up in
an identical lab room, what time the next day (in Montreal time) will the
bee look for
food at the feeder? . Answer: - bee will look for food in the feeder at
3pm (3 hours after 12 in Montreal, but 12pm in Vancouver)
◉ Why should psychologists (scientists who study or treat behavior)
care about
circadian rhythms? Give 4 reasons. . Answer: 1. understanding
motivation: why organisms do what they do
