menstrual cycle - infradian rhythm

• What is the role of circadian rhythm in humans?

  It regulates the cycle of sleeping and waking.
• How does the circadian rhythm relate to the internal body clock?

  The circadian rhythm is governed by an internal body clock that responds to external cues like sunlight.
• What does the term 'ultradian' refer to in biological rhythms?

  'Ultradian' refers to rhythms that occur more than once every 24 hours.
• What is the menstrual cycle in humans?

  The menstrual cycle is a female cycle of fertility lasting approximately 28 days.
• What are the biological aspects of the menstrual cycle?

  • Releasing the egg
  • Thickening of the womb lining
  • Loosening of the womb lining during menstruation
• What hormones regulate the menstrual cycle?

  Estrogen and progesterone.
• What is the significance of endogenous pacemakers in the menstrual cycle?

  They act as an internal body clock regulating biological processes.
• What did McClintock's original research in 1971 reveal about menstrual cycles?

  It showed that women living together tended to synchronize their menstrual cycles.
• What role do pheromones play in menstrual cycle synchronization according to Russell's research?

  Pheromones may act as external cues that influence menstrual cycle synchronization.
• What was the main finding of Stern's 1998 study on menstrual cycles?

  Women adjusted their menstrual cycles based on the menstrual cycle of donor women from whom pheromones were collected.
• What are the criticisms of the idea that pheromones synchronize menstrual cycles?

  • Many studies failed to replicate findings.
  • Variability in menstrual cycle lengths can explain apparent synchronization.
  • Evolutionary arguments are conflicting regarding the adaptive advantage of synchronization.
• What is the evolutionary argument for synchronization of menstrual cycles?

  It may provide an adaptive advantage by preventing one male from dominating a group of females.
• What historical belief is associated with the menstrual cycle?

  Many believed it was controlled by the phases of the Moon.
• What did the study tracking 1.5 million women reveal about menstrual cycles and the Moon?

  There was no link between menstrual frequency and the phases of the Moon.
• What is the correlation between menstrual cycles and chimpanzees?

  Chimpanzees have a 35-day cycle, but this does not support the idea of synchronization due to evolutionary advantages.
• How long is the average menstrual cycle?

  Approximately 28 days.
• What is the significance of the term 'infradian' in biological rhythms?

  'Infradian' refers to rhythms that take longer than a day to complete.
• What does 'circadian' mean in the context of biological rhythms?

  'Circadian' means around the day.
• What is the definition of 'ultradian' rhythms?

  'Ultradian' rhythms are those that occur more than once every 24 hours.
• What is the definition of 'tradian' rhythms?

  'Tradian' rhythms are not a recognized term in biological rhythms.
• What is the impact of seasonal affective disorder on mood?

  It causes mood to lower in winter and improve in summer.
• What is the duration of the menstrual cycle?

  It typically lasts between 24 to 35 days.
• What are the key biological changes during the menstrual cycle?

  Releasing the egg, thickening of the womb lining, and loosening of the womb lining during menstruation.