Infradian and Ultradian rhythm

Question 1

Female menstrual cycle

Answer 1

Cycle about 28 days
Oestrogen = ovary to develop + release egg
Progesterone = helps womb lining to thicken, ready body for pregnancy
Womb lining stripped

Question 2

Exogenous zeitgebers may synchronise menstrual cycles

Answer 2

29 with irregular periods
Pheromones’ taken at different stages, cotton pad under armpits
Cleaned with alcohol and rubbed on upper lip
68% changes to cycle closer to “odour doner”
Influenced by exogenous factors

Question 3

Season affective disorder (SAD)

Answer 3

Seasonal pattern to depression
‘winter blues’
Takes a year to complete
Melatonin in result - during night melatonin secreted until dawn, stops when more sunlight
Lack of light = melatonin secrets for longer

Question 4

Ultradian Rhythm - Stages of sleep

Answer 4

Many in 24 hours

5 distinct stages of sleep (90min to complete)
Stages characterised by different level of brainwaves - EEG

Question 5

Stage 1

Answer 5

4-5%
Light sleep
Muscle activity slows down
Occasional muscle twitching

Question 6

Stage 2

Answer 6

Breathing pattern
Heart rate slows
Decrease in body temp

Question 7

Stage 3

Answer 7

Deep sleep begins
Brain begins to generate slow delta waves

Question 8

Stage 4

Answer 8

Very deep sleep
Rhythmic breathing
Limited muscle activity

Question 9

Stage 5

Answer 9

Rapid eye movement
Brainwaves speed up + dreaming occurs
Muscles relax + heart rate increases
Breathing is rapid and shallow

Question 10

AO3

Answer 10

confounding variables - women menstrual cycle
Stress, diet changes and exercise

Required self-reporting = inaccurate

Based on animal research - synchronisation research
Sea urchins release pheromones’ into surrounding water So other urchins eject sex cells simultaneously

Development of treatment - SAD
Effective treatment of SAD is phototherapy - lightbox simulates morning light - resets melatonin levels