PSYC 388 Questions with Detailed Verified Answers

Page | 1



PSYC 388 Questions with Detailed
Verified Answers

Question:Phase

Ans: - a point within the cycle

- the instantaneous state of the clock

- a position within its cycle

** can refer to range of phases (daily active phase or rest phase)

Question: Period (tau)

Ans: - duration of a complete cycle

Question: Wavelength (lambda)

Ans: - distance between two acrophases (peaks)

- distance a wave travels in one period, or length of one cycle

Question: Amplitude (2 definitions)

Ans: - the range (peak to trough) OR

- half the range (peak to mean/mesor)

Question: Acrophase

Ans: the peak of the curve (sine wave)

Question: What are the four 'circa' rhythms? (and give examples)

, Page | 2

Ans: 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

Question: What two characteristics distinguish these from
other rhythms?

Ans: 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

Question: 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?

Ans: - keep the animal in constant conditions attempting to remove all
rhythmic stimuli

Question: Is the circadian rhythm depicted in this actogram free-running
faster or slower than
24h?

Ans: - staircase <<24hrs

- upside-down staircase >>24hrs

Question: What is meant by temperature compensation, and why is this a
necessary