DIRECTIONS: In the passages that follow, some words and phrases are underlined and numbered. In the answer column, you will find alternatives for the words and phrases that are underlined. Choose the alternative that you think is best, and fill in the corresponding bubble on your answer sheet. If you think that the original version is best, choose “NO CHANGE,” which will always be either answer choice A or F. You will also find questions about a particular section of the passage, or about the entire passage. These questions will be identified either by an underlined portion or by a number in a box. Look for the answer that clearly expresses the idea, is consistent with the style and tone of the passage, and makes the correct use of standard written English. Read the passage through once before answering the questions. For some questions, you should read beyond the indicated portion before you answer.
The following paragraphs may or may not be in the most logical order. You may be asked questions about the logical order of the paragraphs, as well as where to place sentences logically within any given paragraph.
Traveling across time zones particularly Q1 via airplane, can be very disconcerting to the human body, both physically and mentally. When you “gain” or “lose” time going from Point A to Point B, a condition (desynchronosis) Q2 likely affects you in some form. Jet lag is medically considered a sleeping disorder, although it is normally a temporary condition and not as serious Q3 as other sleeping dysfunctions.
Q4 The term “circadian” originates from the Latin circa, meaning “about,” and diem or “day.” Circadian rhythms refer to a variety of daily bodily functions such as temperature changes, sleep patterns, and digestive functions. Normally, the body operates on a 24-hour time period that coincides with the earth’s 24-hour cycle of night and day. The human body generally falls into a routine of sleeping and waking; that is, regular Q5 changes in body temperature, breathing, and digestion take place. In addition Q6 , most who’s inner clocks Q7 cause more sleepiness from 3:00 p.m. to 5:00 p.m. and again from 3:00 a.m. to 5:00 a.m. Body temperature usually rises as the day goes on, quickly drops around midnight, and then begins the cycle of rising again just before 6:00 a.m. Since these Q8 changes occur on a twenty-four-hour cycle, so abrupt time zone changes can understandably upset the body’s highly well-tuned in Q9 system of regulation.
Some symptoms of jet lag include excessive daytime sleepiness or some level of insomnia at night, changes in appetite and/or digestion, moodiness, and difficulty concentrating. Often, after traveling on a plane for long periods Q10 , people will also experience headaches, dry sinuses, earaches, and bloating. However, these symptoms are more likely being attributable Q11 to the conditions of the airplane cabin, which has a very dry pressurized, Q12 atmosphere, and are not symptomatic of jet lag.
 There are steps that can be taken to alleviate the effects of jet lag, primarily as preventive measures.  First, it might be helpful to slightly alter your sleeping schedule for several days before your trip.  If you are 73 going east, for example, Q13 go to bed one hour earlier and rise the next day an hour earlier so that you will be somewhat more acclimated to the new time zone.  Regulating your exposure to light can also be helpful, since light and darkness serve as triggers to the brain.  Before traveling west, expose yourself to evening light and avoid early morning light for several days as a way of simulating the new time zone you’re headed toward.  Some say it takes about one day for every hour of time zone change to completely adjust to the new time zone.  Unfortunately for many, that formula often coincides precisely with the return trip.  Avoiding caffeine and alcohol may also aid your body in adjusting to its new environment. Q14 Q15