Question 1: Define the term 'biological rhythm' in your own words.

Answer: A biological rhythm is a natural, regular change in bodily processes that occurs over a specific period of time, such as sleep or heartbeat cycles.

Question 2: Name the main type of biological rhythm that regulates our sleep and wakefulness.

Answer: Circadian rhythm.

Question 3: Describe what happens to a person's body temperature during a typical 24-hour circadian cycle.

Answer: Body temperature generally rises during the day, reaches a peak in the late afternoon, and drops at night, being lowest in the early morning.

Question 4: Explain why it is important for humans to have regular sleep-wake cycles.

Answer: Regular sleep-wake cycles help maintain good health, support mental and physical functioning, and regulate processes like hormone release and body repair.

Question 5: Identify two factors that can disrupt a person's circadian rhythm.

Answer: Factors include shift work and jet lag caused by crossing multiple time zones.

Question 6: Describe what is meant by 'ultradian rhythms' and give an example.

Answer: Ultradian rhythms are cycles that occur more than once in a 24-hour period, such as the stages of sleep that repeat throughout the night.

Question 7: Sketch a simple diagram showing the pattern of a typical circadian rhythm over a 24-hour period. Label the key points such as 'highest alertness' and 'deepest sleep'.

Answer: A smooth curve that rises during the daytime, peaks in the late afternoon, dips to its lowest point during the early morning hours, with marked points indicating high alertness and deep sleep phases.

Question 8: Explain how exposure to natural light influences the circadian rhythm.

Answer: Natural light helps regulate the circadian rhythm by signaling to the brain when it is daytime, promoting alertness, and helping to initiate sleep when it gets dark.

Question 9: Suggest two ways someone can help reset their circadian rhythm if they have experienced jet lag.

Answer: Getting plenty of natural light during the day and adjusting sleep times gradually before traveling can help reset the circadian rhythm.

Question 10: Why do some people experience 'jet lag' more severely than others?

Answer: Differences in age, individual biological clocks, travel direction, and how quickly the body adapts to new time zones can affect the severity of jet lag.