Biological Rhythms

Question 1

What is a biological rhythm

Answer 1

Any change in physiological activity that repeats periodically in a set pattern

Question 2

Circadian rhythm

Answer 2

One cycle takes approx 24 hours

Eg - metabolic activity
Body temp
Sleep wake cycle

Question 3

Infradian rhythm

Answer 3

One cycle takes longer than 24 hours

Eg - menstruation
Hibernation
SAD

Question 4

Ultradian rhythm

Answer 4

One cycle takes less than 24 hours

Eg- feeding
Stages of sleep
Alertness

Question 5

Sleep wake cycle

Answer 5

Approx 24 hour cycle
Determines patterns of wakefulness and sleepiness
Influenced by endogenous pacemakers and exogenous zeitgebers

Question 6

Endogenous pacemakers

Answer 6

Internal body clocks that influence pattern of bio rhythms
Help maintain regular rhythms in absense of zeitgebers
Need zeitgebers to synchronise rhythms

Question 7

Examples of exogenous pacemakers

Answer 7

Pineal gland
Suprachiasmatic nucleus

Question 8

Exogenous zeitgebers

Answer 8

External stimuli that provide info about elapsed time and prompt changes in bodily activity and the patterns of our biological rhythms

Question 9

Examples of exogenous zeitgebers

Answer 9

Clock
Light

Question 10

Siffre study

Answer 10

French cave explorer
6 months in underground cave in Texas
Separated from natural light / dark cycles
Bodily sleep wake cycle allowed to free run away from exogenous zeitgebers
Ate and slept whenever he wanted
Settled down to regular pattern of around 25-30 hours
Slightly longer than usual cycle