Circadian rhythms Flashcards
1
Q
How long is circadian cycle?
A
20-28 h
2
Q
How long is ultradian cycle?
A
Less than 20 hours
3
Q
How long is circamensual cycle?
A
30 days
4
Q
How long is infradian cycle?
A
Less than 38 hours
5
Q
How long is human period?
A
25 hours
6
Q
Where is SCN?
A
Anterior hypothalamus
7
Q
RHT
A
- Signal from light-dark cycle through retinal hypothalamic tract which is glutamatergic
- Glutamate into SEN - activates neurons
- SEN ontop of optic chiasm
- Circadian rhythms are endogenous - not driven by light-dark cycle
8
Q
When does real time start?
A
0
9
Q
What is ZT 0?
A
Lights on
10
Q
What is ZT 12?
A
Lights off
11
Q
What is CT 0?
A
Subjective lights on
12
Q
What is CT 12?
A
Subjective lights off
13
Q
What is the phase of a clock?
A
How delayed a cycle is compared to lights on
14
Q
What is phase advance?
A
How delayed a cycle is compared to lights on
15
Q
How do clocks work?
A
BMAL1 and CLOCK activate PER-CRY
PER-CRY inhibit BMAL1 and CLOCK
