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.
Which of the following is NOT a product of photosynthesis?
- A. Oxygen
- B. Sugar
- C. Nitrogen
- D. ATP
Correct Answer: C
Rationale: The correct answer is C: 'Nitrogen.' During photosynthesis, oxygen, sugar, and ATP are all products of the process. Oxygen is released into the atmosphere, sugar is the main product used by the plant for energy and growth, and ATP is a form of stored chemical energy. However, nitrogen is not a direct product of photosynthesis. The process primarily involves the conversion of carbon dioxide and water into sugars and oxygen, with nitrogen not being part of the immediate products.
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Health Care's Numbers Game: The game of health care is a risky one. Today emergency rooms are acting as primary care physicians for thousands of patients. This trend produces a vicious cycle of hospitals raising emergency room costs and passing that increase along to paying patients, who in turn pass it along to insurance companies, who in turn raise rates so even more people cannot afford the premium or the co-payment.
For years, indigent people have used emergency rooms for very minor illnesses rather than seeing an outside doctor, but now emergency rooms are seeing people with insurance, but who cannot afford the co-payment or the deductible for the office visit.
If we don't change the way the healthcare game is played, we're all going to lose.
According to the passage, why are insurance companies raising insurance rates?
- A. Hospitals are mismanaged and therefore are overspending their budgets.
- B. They need to make more money to stay competitive.
- C. Hospitals are passing down the costs of giving care to people without insurance.
- D. Doctors are demanding higher salaries.
Correct Answer: C
Rationale: The correct answer is C: Hospitals are passing down the costs of giving care to people without insurance. The passage clearly states that hospitals are raising emergency room costs due to acting as primary care physicians for thousands of patients, including those without insurance. This increase in costs is then passed along to paying patients, who further pass it on to insurance companies. This leads insurance companies to raise rates to compensate for the increased costs incurred due to providing care to individuals without insurance.
Incorrect choices:
A: Hospitals being mismanaged does not directly relate to insurance companies raising rates.
B: Insurance companies raising rates is not solely to make more money to stay competitive.
D: There is no mention of doctors demanding higher salaries as a reason for insurance companies raising rates.
Subjective exams measure your ability in several areas. Besides recall information, you must be
able to realize content logically and intelligently express yourself in a clearly understood manner. Subjective test provide opportunity for students to show their broad knowledge of a subjective
area. Answers may be in the form of paragraphs or lengthy essays. When your review for an essay exam, concentrate on main ideas rather than details. Since essay tests are less to a few questions, they are likely to deal with more important ideas of a subject. Prepare a list of question you think might be asked. Write an answer to each of your questions. Rather than writing complete sentence down your thoughts in outline form. Doing so will help
you organize the information so that you can express yourself clearly.
When you take the test, read through all the questions before you start to write. Allot time for each question, spending more time for questions worth the most points. Read each question carefully to determine exactly what they are asked. Pay attention to words such as define, illustrate, explain, list, compare, and contrast. Each work requires a different type of response. Write a brief outline of your answer on scrap paper or the back of the test. Make sure you include all the important ideas that are within the limits of the question. In other words, do not write more than is asked for each answer. When you write your answer, keep it specific and as brief as possible. In the introductory sentence it is often helpful to make a general statement that includes
important points addressed in each question. Such a topic sentence serves as a framework for your answer. Then use your outline to develop the main point and subtopics. Add substance to
your answer by including as many facts as possible to support your answer.
Check your paper before you submit it. Look for mistakes in grammar, spelling, sentence
structure, and punctuation. Unless you are certain an answer is wrong, do not change it. Your answer is an educated guess and is usually your best chance of answering correctly.
In the above passage, the word 'subjective' refers to test questions that:
- A. Allow you to choose an answer
- B. Are matching
- C. Are true or false
- D. Require you to write your own answer
Correct Answer: D
Rationale: The term 'subjective' in the passage refers to test questions that require you to write your own answer, as mentioned in the text. Subjective tests typically involve expressing your understanding and knowledge in your own words, often through paragraphs or essays. This type of assessment allows students to demonstrate their comprehension and analytical skills by formulating responses based on their interpretation of the content, rather than selecting from predefined options. Therefore, the correct answer is D: 'Require you to write your own answer.'
Over the last few decades, medical experts have changed their thinking on the health effects of some common foods and beverages. Higher-fat foods and some alcoholic beverages like red wine and beer, once viewed as top threats to a healthy lifestyle, are now seen by many as less harmful and even as having some health benefits. But there is perhaps no topic that the medical community has reversed its
thinking on more often than coffee. Since long before the advent of modern medicine, public opinion regarding the health effects of coffee has been diverse and ever-changing. Opinion on coffee's health effects can be traced back several centuries. In the 1600s, doctors in England touted coffee as a cure for alcoholism, but some women complained that coffee was making their husbands impotent. They may have been correct, as caffeine is a
diuretic and can irritate the prostate (dehydration and prostatitis can both lead to erectile dysfunction). In the late 1700s, coffeehouses began opening all over colonial America, where coffee was seen as a healthy stimulant that helped the colonists work longer hours. But by the early 1900s, public concern grew as coffee consumption was blamed for a variety of common ailments, such as nervousness, indigestion, and insomnia. In the 1970s, medical journals published studies that linked coffee consumption with high blood pressure and an increased risk of heart attacks. In 2001, a meta-study indicated that coffee was responsible for a 20% increase in risk for urinary tract cancer. But starting in 2007, to the surprise of many, meta-studies began to show positive health effects of coffee consumption. A 2007 study showed that coffee was viewed by many as "practically a health food." However, CNN also warned that given the long history of flip-flops on the health effects of coffee, medical and public opinion on coffee could easily turn negative again.
Based on the passage, which statement is supported?
- A. Recent studies indicate that coffee consumption increases the risk of liver cancer.
- B. There is some scientific evidence that drinking coffee reduces indigestion.
- C. Published studies have found that drinking coffee may increase the risk of heart attack.
- D. There is no reported evidence of any link between coffee consumption and stroke.
Correct Answer: D
Rationale: The passage discusses various historical shifts in the perception of coffee's health effects. While it mentions studies linking coffee consumption to high blood pressure and an increased risk of heart attacks in the 1970s, there is no mention of any reported evidence linking coffee consumption to stroke. Therefore, the statement that there is no reported evidence of any link between coffee consumption and stroke is supported by the passage.
Electrocardiogram
The rhythmic sounds of "beep... beep... beep..." signify the measurement of the heart muscle's strength. This rhythmic signal varies from person to person and is recorded as an electrocardiogram (ECG). Within the body, a complex array of systemic neural responses generates electric currents that can be detected on the skin's surface. When a person is connected to an amplifier, these impulses are captured by an electrocardiograph. Most of the information gathered pertains to the heart, as it emits electric currents in waves. This "wave of excitation" propagates through the heart wall and is associated with electrical changes. The process occurs in three distinct phases. First, the "wave of excitation," accompanied by an electrical change, lasts for about 1 to 2 seconds following the contraction of the cardiac muscle. These electrical impulses are rhythmically discharged from the sinoatrial (SA) node, which acts as the heart's natural pacemaker, signaling the atrium to contract. The peak of the ECG reading is attributed to the atrioventricular (AV) node, which triggers the excitation of the ventricles. Finally, as the ventricles relax, any changes in the wave pattern can alert trained medical personnel to potential abnormalities within the heart.
What are the three phases of the "wave of excitation"?
- A. The discharge from the SA node, the peak ECG, and the excitement of the ventricle.
- B. The excitement of the ventricle, the relaxing of the ventricle, and the systemic neural response.
- C. The contraction of the atrium, the relaxation of the atrium, and the contraction of the ventricle.
- D. The excitation of the atrium, the excitement of the ventricle, and the relaxing of the ventricle.
Correct Answer: D
Rationale: The correct answer is D: 'The excitation of the atrium, the excitement of the ventricle, and the relaxing of the ventricle.' The 'wave of excitation' in the heart occurs in three main steps. Firstly, the excitation starts with the discharge from the SA node, indicating the contraction of the atrium. Secondly, the peak ECG reading is caused by the excitement of the ventricle. Lastly, the wave ends with the relaxing of the ventricle. Understanding these steps is crucial for interpreting electrocardiograms and identifying any abnormalities in the heart's electrical activity.
It is a well-known fact that it takes the Earth approximately 365 days to orbit the Sun. At the same time, the Earth revolves or spins around itself over the course of 24 hours, which explains why we experience day and night. One half of the Earth is always facing the Sun, while the other half is facing away. As a result, different time zones divide the globe. Moving suddenly from one time zone to another, such as when flying from Asia to North America, can cause jet lag. People often feel tired, wake up suddenly during the night, and cannot return to sleep. It takes time to adjust to a new time zone. Another important factor to consider is the slight tilt of the Earth toward the Sun. The Earth does not stand straight but leans slightly to one side. Therefore, when it revolves around the Sun, the middle part of the Earth is always closer to the Sun and receives more heat. This area is called the equator, and the regions above and below it are known as the tropics. Countries located in the tropics receive a consistent amount of daylight throughout the year, with the Sun rising at 6 AM and setting at 6 PM. In contrast, the tips of the Earth, or the poles, receive hardly any light because they are so far from the Sun. There are two main seasons at the poles: 6 months of summer, when the Sun is always shining (even at night), and 6 months of winter, characterized by constant darkness. Between the tropics and the poles lies the temperate zone, where there are four distinct seasons. The Sun rises and sets at different times throughout the year. In spring and summer, it gets light earlier; in fall and winter, it gets dark earlier. People living in temperate zones take advantage of this variation to maximize their daylight exposure. At the beginning of spring, countries in Europe and North America readjust their clocks by moving them an hour ahead. As a result, the Sun does not set around 7 or 8 PM as usual, but an hour later. This practice is called Daylight Savings Time (DST) and lasts until the beginning of fall, when people move their clocks back one hour to Standard or Regular Time. It is believed that Benjamin Franklin first suggested the introduction of Daylight Savings Time in the 18th century, but the first serious proposal came in 1907 from William Willet. However, his idea was shelved by the British government, which deemed it unnecessary. Daylight Savings Time was first implemented by the German government in 1916 in order to save energy during World War I. Shortly after, the United Kingdom followed suit, with the United States doing the same in 1918. The law was unpopular, as people had to wake up earlier, leading many to experience a feeling similar to jet lag. However, the energy crisis of the 1970s forced the U.S. to establish Daylight Savings Time as law. Studies showed that the introduction of Daylight Savings Time in the spring saved the U.S. 10,000 barrels of oil per day between 1974 and 1975. It also prevented 2,000 traffic injuries and 50 traffic-related deaths, saving the country $28 million. Currently, Americans switch to Daylight Savings Time on the first Sunday in April and revert to Standard Time on the last Sunday in October. As of 2007, the time adjustments occur even earlier in March and November.
What does the sentence ‘It takes time to get used to a new time zone’ mean in paragraph 1?
- A. A flight between Asia and North America takes a long time.
- B. Changing time zones makes people feel tired.
- C. People need time to feel comfortable with a new time zone.
- D. It may take weeks to get used to jetlag.
Correct Answer: B
Rationale: The sentence ‘It takes time to get used to a new time zone.’ in paragraph 1 refers to the fact that changing time zones causes jetlag, making people feel tired, waking up suddenly during the night, and having difficulties sleeping. This adjustment period is needed for the body to adapt to the new time zone.
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