Reading Comprehension Related

The immune system is a network of cells, tissues, and organs that defends the body against attacks by foreign invaders. These invaders are primarily microbesĆ¢ā‚¬ā€¯tiny organisms such as bacteria, parasites, and fungiĆ¢ā‚¬ā€¯that can cause infections. Viruses also cause infections, but are too primitive to be classified as living organisms. The human body provides an ideal environment for many microbes. It is the immune systemĆ¢ā‚¬ā„¢s job to keep the microbes out or destroy them.
The immune system is amazingly complex. It can recognize and remember millions of different enemies, and it can secrete fluids and cells to wipe out nearly all of them. The secret to its success is an elaborate and dynamic communications network. Millions of cells, organized into sets and subsets, gather and transfer information in response to an infection. Once immune cells receive the alarm, they produce powerful chemicals that help to regulate their own growth and behavior, enlist other immune cells, and direct the new recruits to trouble spots.
Although scientists have learned much about the immune system, they continue to puzzle over how the body destroys invading microbes, infected cells, and tumors without harming healthy tissues. New technologies for identifying individual immune cells are now allowing scientists to determine quickly which targets are triggering an immune response.
Improvements in microscopy are permitting the first-ever observations of living B cells, T cells, and other cells as they interact within lymph nodes and other body tissues.
In addition, scientists are rapidly unraveling the genetic blueprints that direct the human immune response, as well as those that dictate the biology of bacteria, viruses, and parasites. The combination of new technology with expanded genetic information will no doubt reveal even more about how the body protects itself from disease.

What is the meaning of the word 'enlist' as it is used in the second paragraph?

• A. call into service
• B. write down
• C. send away
• D. put across

The Water Cycle
Water is needed to sustain practically all life functions on planet Earth. A single drop of this compound is composed of an oxygen atom that shares its electrons with each of the two hydrogen atoms.
The cycle starts when precipitation, such as rain, snow, sleet, or hail, descends from the sky onto the ground. Water that is not absorbed immediately from the precipitation is known as runoff. The runoff flows across the land and collects in groundwater reservoirs, rivers, streams, and oceans.
Evaporation takes place when liquid water changes into water vapor, which is a gas. Water vapor returns to the air from surface water and plants.
Ultimately, condensation happens when this water vapor cools and changes back into droplets of liquid. In fact, the puffy, cotton clouds that we observe are formed by condensation. When the clouds become heavily laden with liquid droplets, precipitation ensues.

What was the authorā€™s primary purpose for writing this essay?

• A. To persuade the reader to conserve water
• B. To persuade the reader that runoff is not the best way to collect water
• C. To analyze different types of runoff
• D. To inform the reader about the stages of the water cycle

The White Elephant: Centuries ago, In Siam, now known as Thailand, it was the custom of the rulers to give a white elephant to those who displeased them. The recipient could not give the elephant to anyone else, as it was a gift from the ruler, who would be greatly displeased should the recipient not receive the gift graciously or care for the elephant in a grand style. This monetary burden could be a major liability to the recipient and in many cases the entire family became impoverished.
This is the origin of the term 'white elephant' as it is used today to denote an unwanted gift. The parlor game of gift exchange played during the holiday season is an offshoot of this. In this game, everyone brings a wrapped gift and the gifts are exchanged by drawing numbers and picking a gift in turn. The second person can choose a new gift or steal the first one. It is all in good fun, and people enjoy giving silly gifts and 'stealing' someone else's gift.

How did the people regard a white elephant?

• A. If a village elder received a white elephant, the entire village shared in the supply of meat.
• B. The people of Siam vied for the honor of receiving the king's gift of a white elephant.
• C. People tried very hard not to offend the king so they would not receive a white elephant.
• D. White elephants were highly prized as they were very hard workers in the cane fields.

Lightning Strikes
The old wives' tale of "Lightning never strikes twice" has been proven untrue time and time again. Lightning forms from negative and positive charges within clouds and from the earth below. When these charges react with each other, the air between the cloud and the earth ionizes, which produces a lightning flash. Lightning is actually a series of multiple events consisting of a leader stroke of lightning, followed by as many as 40 smaller strokes of lightning. Being just split seconds apart, these strokes of lightning often reflect off the lining of the clouds.
Lightning rods that extend from above the roof to the ground protect buildings by forming a low resistance path for the lightning so that the lightning does not enter the building, but rather defuses as it penetrates the ground.
Some myths about lightning need to be explained. Lightning does strike tall buildings often, and during a particularly violent storm, a tall building may be hit by lightning several times. The safest place during a thunder and lightning storm is in a metal car or lying flat, face down, in the open, not under a tree as the myth suggests.
Many people believe that thunder and lightning are connected; however, this proves to be true only about 50% of the time, so if you're waiting for the clap of thunder, you're missing out on some exciting strokes of lightning!
Lightning causes injuries, deaths, and forest fires each year. However, some scientists reveal the positive aspects of lightning because it releases nitrogen into the atmosphere which the raindrops then deliver to earth to fertilize our soil.

When taking cover from lightning, you should:

• A. Stand under a tree for protection
• B. Seek shelter in a wooden building
• C. Get into a metal car, or lie flat on the ground
• D. Stay outside and continue your activity

Food
Food and drink are necessary and desirable, but their
abuse can cause serious physical and metal problem.
Many physicians believe that overeating is one of the
country's main health problems, since it places a great
strain on the heart, can lead to diabetes, and often shortens
the individual's life span. To fill an emotional void. People
often turn to food when they are bored or lonely.
Another area of concern is alcohol consumption. The
results of alcohol abuse are widely publicized. The social
drinker who becomes alcoholic, the drunken driver's
contribution to highway death, spousal and child abuse,
are all concomitant problems associated with alcohol
abuse.

The information presented in this article is?

• A. Against eating and drinking
• B. Against drinking alcohol
• C. Against eating rich foods
• D. Unbiased in its approach