Nokea
Photosynthesis is a process used by plants, algae, and certain bacteria to convert light energy into chemical energy stored in sugar molecules. This process is fundamental to life on Earth as it provides the primary source of energy for nearly all organisms. The energy is captured from sunlight by a pigment in the plants called chlorophyll, which gives plants their green color.
During photosynthesis, carbon dioxide from the air and water from the soil react in the presence of light to form sugars and oxygen. The oxygen is released into the atmosphere, which is crucial for the survival of most life forms on Earth. The sugars produced are used by the plant for energy and growth, storing excess energy as starch.
The process occurs in two main stages: the light-dependent reactions and the Calvin cycle. In the light-dependent reactions, energy from sunlight is absorbed by chlorophyll and converted into stored chemical energy in the form of ATP and NADPH. The Calvin cycle uses the ATP and NADPH produced in the light-dependent reactions to convert carbon dioxide into glucose.
Photosynthesis not only sustains plant life but also maintains the atmospheric oxygen levels and is a key factor in the carbon cycle, helping to regulate Earth's climate.
What is the primary function of photosynthesis?
- A. To produce oxygen and nitrogen
- B. To convert light energy into chemical energy
- C. To absorb carbon dioxide from the atmosphere
- D. To release water vapor into the air
Correct Answer: B
Rationale: The primary function of photosynthesis is to convert light energy into chemical energy stored in sugar molecules. During photosynthesis, plants, algae, and certain bacteria use sunlight to synthesize sugars from carbon dioxide and water. This process is essential for providing energy to nearly all organisms on Earth. While photosynthesis releases oxygen into the atmosphere as a byproduct, its main purpose is the conversion of light energy into chemical energy, making choice B the correct answer.
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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.
In paragraph two, the word penetrates means
- A. To be absorbed by the mind.
- B. To pierce.
- C. Having or showing great insight.
- D. To discover or understand.
Correct Answer: B
Rationale: The correct answer is B: To pierce. The word "penetrates" in the context of the passage refers to lightning making its way through the ground as it strikes. Lightning rods provide a low-resistance path for the lightning to follow, allowing it to pierce through the ground safely. Choices A, C, and D do not accurately reflect the meaning of the word "penetrates" in this context. Choice A, "To be absorbed by the mind," does not relate to the physical action of lightning entering the ground. Choice C, "Having or showing great insight," and choice D, "To discover or understand," do not align with the action of lightning piercing through the ground. Therefore, choice B is the correct answer as it directly corresponds to the physical action described in the passage.
Glass
I wonder who first discovered glass. This commodity has been a part of civilization from the very beginning. Imagine a world without glass! How dark and dismal it would be. No windows, corrective lenses, telescopes, microscopes, cameras, sparkly drinking containers or mirrors. Life would not be the same without this wonderful discovery. Thank you, whoever found glass!
Glass is not an element, but a combination of several elements. It is a hard, brittle, transparent solid material composed mainly of silica, with additives to change the character of the glass. Common additives are soda, lime, lead, and boron. Each additive changes the properties of the final product. Soda and lime are the most common additives, accounting for about 90% of glass production. Adding lead increases reflectivity, causing the glass to "sparkle." The addition of boron changes the thermal and electrical properties of glass, allowing cookware that can be used in the oven without shattering.
What statement is implied by the article?
- A. Glass is an essential part of our lives.
- B. Glass is rarely used in everyday items.
- C. Glass production is harmful to the environment.
- D. Glass technology is outdated and ineffective.
Correct Answer: A
Rationale: The correct answer is A: 'Glass is an essential part of our lives.' The article highlights the significance of glass in various aspects of human life, such as windows, corrective lenses, telescopes, microscopes, cameras, drinking containers, and mirrors. It emphasizes how life would be different and lacking without the presence of glass. Furthermore, the text expresses gratitude for the discovery of glass, indicating its essential role and impact on civilization. Hence, the implication throughout the article is that glass is indeed an indispensable and fundamental component of our daily existence.
Violence: Lately, studies have been done to decide whether a relationship exists between violence on television and mounting violence in the streets of the United States. More and better research is needed to assess fully the effects of exposure to violence on human behavior. However, early results seem to indicate that some people are influenced negatively by what they see on TV, especially young children. Since children born today, on an average, are exposed to seven hours of TV a day, some changes seem needed.
Consultants have advised network officials to reconsider certain policies if they wish to avoid the pitfalls of increased government regulations.
The theme of the article seems to be to
- A. persuade people to support censorship of television.
- B. inform people about the debate over TV violence.
- C. alarm people about the effects of television violence.
- D. persuade people to relax controls over TV programming.
Correct Answer: B
Rationale: Correct Answer: B (inform people about the debate over TV violence)
Rationale:
1. The passage discusses studies on the relationship between TV violence and real-life violence.
2. It mentions the need for more research to fully understand the effects of violence on behavior.
3. It emphasizes the negative influence of TV violence, especially on young children.
4. The passage concludes with a recommendation for network officials to reconsider policies.
5. Therefore, the theme is to inform people about the ongoing debate and concerns regarding TV violence.
Summary of Incorrect Choices:
A: The passage does not explicitly advocate for censorship of television.
C: While the passage discusses negative effects of TV violence, it does not aim to alarm people.
D: The passage does not suggest relaxing controls over TV programming; in fact, it hints at the need for changes.
The Summer Olympic Games. Once every four years the countries of the world send their best and brightest to participate in the Summer Olympic Games. The site for the event is decided years before, and most countries contend strongly for the privilege to host the Games. The 2008 games were held in Bejing, China.
There is a lot of pageantry and tradition attached to the event. The opening ceremony is elaborate and awe-inspiring. China put on a spectacularly beautiful fireworks display to welcome the world's athletes in 2008.
The track events, water events (swimming, diving) and precision activities such as archery and rhythmic gymnastics are wonderful to watch. Seeing these athletes perform their special skills is a treat for those of us who achieve a vicarious satisfaction from it. Everyone roots for the athletes from their own country and we thrill when our anther is played during the medal ceremony. Being an Olympian is an honor every athlete dreams of.
How often are the Summer Olympic Games held?
- A. Every two years.
- B. Every four years.
- C. Annually.
- D. Once a decade.
Correct Answer: B
Rationale: The Summer Olympic Games are held 'once every four years,' as stated in the text. This timeframe allows countries to send their best athletes to participate. The correct answer is B, 'Every four years,' making it a significant and eagerly anticipated global event. The four-year interval also allows for ample time for countries to prepare, build excitement, and showcase their best talents on a world stage.
Blood Pressure Regulators
The body is composed of systems that have evolved and diversified in order to maintain the natural functions and processes they regulate. One such system that has these regulators is the bodyĆ¢Ä‚¬Ä„¢s cardiovascular system. The bodyĆ¢Ä‚¬Ä„¢s pump, which regulates the flow of vitally needed oxygen to all cells of the body, as well as the discard of carbon dioxide and other waste products, is the heart.
Because blood pressure varies at different points within the body, differing components are needed to keep the bodyĆ¢Ä‚¬Ä„¢s blood pressure regulated. Three of the basic components are baroreceptors, chemoreceptors, and the kidneys.
Baroreceptors are stretch receptors composed of fine branching nerve endings and are contained along the walls of the arteries near the heart and in other areas of the body as well. Impulses are related to this stretching along the arterial walls, which causes these baroreceptors to send out even more impulses to the heart, arteries, and veins, causing the blood pressure to go either up or down.
Chemoreceptors are located along the walls of the arteries and monitor changes in oxygen level, carbon dioxide, and pH. Just think! A fall in oxygen causes receptors to send impulses to raise the blood pressure.
The kidneys play a role in regulating blood pressure by absorbing salts and water and removing wastes. Hormones secreted by the adrenal cortex cause the kidney to keep or let go of any salt and water. This has an influence on blood volume and consequently on blood pressure.
What is the primary purpose of the writer in this passage?
- A. To inform the reader about the dangers of high blood pressure
- B. To inform the reader how high blood pressure leads to a higher risk of heart attack
- C. To inform the reader how the cardiovascular system regulates blood pressure
- D. To persuade the reader that controlling one's blood pressure is important
Correct Answer: C
Rationale: The primary purpose of the writer in this passage is to inform the reader about how the cardiovascular system regulates blood pressure. The passage discusses the different components involved in regulating blood pressure, such as baroreceptors, chemoreceptors, and the kidneys. It explains their roles in maintaining blood pressure levels within the body. There is no direct focus on dangers of high blood pressure, heart attack risks, or persuading the reader to control blood pressure, making option C the correct choice.