The Natural Sleep Cycle (Listening)

 1) What is the lecture mainly about?

A) The chemically programmed human sleep cycle.
B) An important experiment on sleep.
C) Sleep cycles of different animals.
D) The variety of sleep patterns observed in humans.


2) Why does the speaker mention horseshoe crabs?

A) To point the ability of most animals to "sense" time.
B) To provide an example of a biological clock.
C) To illustrate the sleep differences between humans and animals.
D) To explain how tides affect animal behavior.


3) What can be inferred about the lecturer?

A) Her sleep patterns are unnatural.
B) She disagrees with the conclusions of the experiment.
C) She endeavors to sleep 12 hours per day.
D) She conducts unethical research.


4) What were the results of the experiment discussed in the lecture? (Choose 2 answers)

A) The natural sleep cycle of a human was determined to be two periods of 4 hours.
B) The participants in the experiment had trouble adjusting to the lack of daylight and spent a significant period of time feeling restless each night.
C) The subjects' lack of sleep affected their productivity during the experiment.
D) The participants claimed to feel truly rested for the first time.


5) At 3:29, the speaker says, "So, cut to the modern day. We're living in a culture of jet lag, global travel, 24-hour business, shift work. And you know, our modern ways of doing things have their advantages, but I believe we should understand the costs."

Why does the speaker say "So, cut to the modern day"?

A) She believes work hours need to be limited in modern society.
B) She thinks that the globalized society needs to eliminate unnatural sleep cycles.
C) She is emphasizing a preference for an older way of life.
D) She is making a transition between different points of her lecture.