Endogenous Pacemakers and Exogenous Zeitgeibers

• What are the two types of regulators of biological rhythms mentioned?

  Endogenous pacemakers and exogenous zeitgebers
• How do endogenous pacemakers affect the sleep/wake cycle?

  They regulate biological cycles internally
• What are exogenous zeitgebers?

  External cues affecting biological rhythms
• What is the role of the SCN in the brain?

  It regulates the sleep/wake cycle
• What hormone does the pineal gland produce?

  Melatonin
• What happens to the sleep/wake cycle when the SCN is damaged?

  It can completely disappear
• What did the study on chipmunks reveal about the SCN?

  It is crucial for maintaining sleep/wake cycles
• What was the outcome of transplanting brain cells from mutant hamsters?

  Normal hamsters adopted a 20-hour cycle
• How does melatonin affect sleep?

  It promotes sleepiness and regulates sleep cycles
• What is the relationship between melatonin and light exposure?

  Melatonin production is influenced by light
• How can social cues affect sleep/wake cycles?

  They help establish regular sleep patterns
• What is a key factor in developing a circadian rhythm in babies?

  Parental influence on sleep schedules
• How can light exposure help with jet lag?

  It can reset circadian rhythms effectively
• What did Campbell and Murphy's study reveal about light detection?

  Light can be detected by other body receptors
• What are some methodological issues with animal studies on the SCN?

  Generalization to humans is difficult
• What ethical concerns arise from animal studies on the SCN?

  Potential harm and risk to animals
• What did Perez's study suggest about circadian rhythms?

  They can exist without light exposure
• How does age affect circadian rhythms according to the studies mentioned?

  Age can alter the length of cycles
• What is the significance of the interactionist system in biological rhythms?

  Endogenous and exogenous factors interact
• What is the primary function of the SCN?

  To act as the master clock