Core Academic Skills Assessment Reading: Key Ideas and Details — Questions and Answers
Question 1: Read the passage: 'Photosynthesis converts light energy into chemical energy stored in glucose. Chloroplasts, found in plant cells, contain chlorophyll that absorbs sunlight. Water and carbon dioxide are the raw materials, while oxygen is released as a byproduct.' Which sentence best states the central idea?
- Plants produce oxygen through a process involving chlorophyll.
- Photosynthesis is the process by which plants convert light into stored chemical energy. (Correct answer)
- Chloroplasts absorb sunlight and release oxygen into the atmosphere.
- Carbon dioxide and water are essential to plant survival.
Correct answer: Photosynthesis is the process by which plants convert light into stored chemical energy.
The passage describes photosynthesis as converting light energy into chemical energy, which is the central idea encompassing all other details.
Question 2: A passage states: 'Urban heat islands occur when cities absorb and retain more heat than surrounding rural areas. Dark surfaces like asphalt and rooftops absorb solar radiation. Reduced vegetation limits cooling through evapotranspiration. Waste heat from vehicles and buildings also contributes.' Which detail is NOT explicitly stated?
- Dark surfaces absorb solar radiation.
- Cities retain more heat than rural areas.
- Urban heat islands cause drought conditions. (Correct answer)
- Reduced vegetation limits cooling.
Correct answer: Urban heat islands cause drought conditions.
The passage never mentions drought conditions; all other options are directly stated in the text.
Question 3: A paragraph concludes: 'Therefore, regular exercise is essential not only for physical health but also for cognitive function.' What is the role of this final sentence?
- It introduces a new argument about cognitive science.
- It summarizes the main idea of the paragraph by restating the central claim. (Correct answer)
- It provides a counterargument to the paragraph's evidence.
- It offers a specific statistic to support the paragraph's claims.
Correct answer: It summarizes the main idea of the paragraph by restating the central claim.
A concluding sentence introduced by 'therefore' typically restates or synthesizes the paragraph's central claim.
Question 4: Read this excerpt: 'Despite its reputation as a desert wasteland, Antarctica receives less annual precipitation than the Sahara, technically classifying it as a polar desert. Yet it holds about 70% of Earth's fresh water.' The word 'yet' signals what relationship between the two sentences?
- The second sentence provides a cause for the first sentence.
- The second sentence contradicts or contrasts with what the first sentence implies. (Correct answer)
- The second sentence repeats the information in the first sentence.
- The second sentence gives an example that supports the first sentence.
Correct answer: The second sentence contradicts or contrasts with what the first sentence implies.
'Yet' is a contrast signal word, indicating that Antarctica being a dry desert contrasts with the surprising fact that it holds vast fresh water.
Question 5: A student reads a passage about ocean acidification. The passage says: 'Since the Industrial Revolution, ocean pH has dropped from 8.2 to 8.1.' Which inference is most directly supported by this detail?
- The ocean will become completely acidic within 50 years.
- Human industrial activity has contributed to measurable changes in ocean chemistry. (Correct answer)
- A pH of 8.1 is harmful to all marine organisms.
- Ocean acidification only occurs near industrial coastlines.
Correct answer: Human industrial activity has contributed to measurable changes in ocean chemistry.
The detail links the pH drop to the Industrial Revolution, directly supporting the inference that human industry has changed ocean chemistry.
Question 6: Passage: 'The printing press, invented by Gutenberg around 1440, made books affordable and accessible. Literacy rates rose across Europe. Ideas spread faster than ever before, fueling the Renaissance and Reformation.' Which statement best summarizes the passage?
- Gutenberg invented the printing press and became famous throughout Europe.
- The printing press reduced the cost of books significantly in the 15th century.
- Gutenberg's printing press accelerated literacy and the spread of ideas, transforming European society. (Correct answer)
- The Renaissance and Reformation were caused entirely by advances in printing technology.
Correct answer: Gutenberg's printing press accelerated literacy and the spread of ideas, transforming European society.
The best summary captures the cause (printing press) and its broad effects (literacy, spread of ideas, societal transformation), as described across all three sentences.
Question 7: Read: 'Many historians argue that World War I was caused by a complex web of alliances, nationalism, imperialism, and militarism. The assassination of Archduke Franz Ferdinand was the spark, but the underlying powder keg had been building for decades.' What does the 'powder keg' metaphor suggest?
- The war began suddenly without any prior warning signs.
- Explosive materials were used as a primary weapon in the war.
- Tensions in Europe had been accumulating and were ready to erupt before the assassination. (Correct answer)
- Franz Ferdinand's death directly caused all the underlying political problems.
Correct answer: Tensions in Europe had been accumulating and were ready to erupt before the assassination.
A powder keg is an explosive container; the metaphor implies that European tensions were built up and primed for conflict before the triggering event.
Question 8: A passage about sleep research states: 'REM sleep is associated with vivid dreaming. Studies show that during REM, the brain processes emotional memories. Disrupting REM sleep impairs emotional regulation the following day.' Which title best captures the main idea?
- Why Dreaming Makes You Happy
- REM Sleep and Its Critical Role in Emotional Memory Processing (Correct answer)
- How to Improve Your Sleep Schedule
- The Stages of Sleep Explained
Correct answer: REM Sleep and Its Critical Role in Emotional Memory Processing
The passage specifically focuses on REM sleep's function in processing emotional memories, making that the central idea.
Question 9: Passage: 'Critics praised the novel's vivid imagery and complex characters. However, some readers found the nonlinear timeline confusing. Despite mixed reviews, the book sold over two million copies.' Which sentence expresses a detail rather than the main idea?
- The novel received both praise and criticism from different audiences.
- Critics praised the novel's imagery and complex characters. (Correct answer)
- Despite mixed reactions, the book achieved commercial success.
- The novel's reception was divided but ultimately commercially successful.
Correct answer: Critics praised the novel's imagery and complex characters.
The praise for imagery and characters is a specific supporting detail, while the main idea is that the novel had mixed but ultimately commercially successful reception.
Question 10: Read: 'In 2019, over 8 million metric tons of plastic entered the ocean. Sea turtles often mistake plastic bags for jellyfish and consume them. Microplastics have been detected in fish tissue consumed by humans.' What is the most reasonable inference about the author's purpose?
- To explain how sea turtles navigate ocean currents
- To highlight the wide-ranging negative impact of plastic pollution on ecosystems and human health (Correct answer)
- To argue that humans should stop eating fish entirely
- To describe the manufacturing process of plastic products
Correct answer: To highlight the wide-ranging negative impact of plastic pollution on ecosystems and human health
The progression from ocean plastic volume, to wildlife impact, to human health effects signals the author's intent to show plastic pollution's broad harmful reach.
Question 11: A passage reads: 'Ancient Romans built roads so durable that some are still intact today. Engineers used layers of sand, gravel, and stone with a slightly curved surface to drain rainwater.' Which detail directly supports the claim that Roman roads were built to last?
- Romans used sand as one of the road materials.
- Some Roman roads remain intact thousands of years later. (Correct answer)
- The roads had a slightly curved surface design.
- Roman engineers were trained in construction techniques.
Correct answer: Some Roman roads remain intact thousands of years later.
The fact that some roads remain intact today is direct evidence supporting the durability claim made in the first sentence.
Question 12: Read this passage: 'In the 1800s, doctors frequently washed their hands only after surgery, not before. Ignaz Semmelweis proposed that handwashing before procedures could save lives, but his idea was ridiculed. Only after Pasteur's germ theory gained acceptance did handwashing become standard.' What does the passage imply about scientific progress?
- Scientific breakthroughs are always immediately accepted by the medical community.
- Pasteur discovered handwashing before Semmelweis proposed it.
- New medical ideas often face resistance before being validated by broader scientific understanding. (Correct answer)
- Surgeons in the 1800s were less intelligent than modern doctors.
Correct answer: New medical ideas often face resistance before being validated by broader scientific understanding.
The passage shows that Semmelweis's correct idea was rejected until germ theory provided a framework for understanding it, implying resistance to new ideas is common.
Question 13: A paragraph begins: 'Not all renewable energy sources are created equal.' The sentences that follow discuss water requirements, land use, and intermittency of solar and wind power. What is the function of the opening sentence?
- It provides statistical evidence about energy production rates.
- It introduces a contrast that the rest of the paragraph will develop. (Correct answer)
- It summarizes the conclusion drawn from the following details.
- It defines what renewable energy means for readers.
Correct answer: It introduces a contrast that the rest of the paragraph will develop.
The opening sentence signals that despite being in the same category, renewable sources differ — a contrast that the following details elaborate on.
Question 14: Passage: 'The Amazon rainforest produces about 20% of the world's oxygen and houses 10% of all species on Earth. Deforestation rates have accelerated in recent years, with millions of acres cleared annually. Scientists warn of a tipping point beyond which the forest cannot regenerate.' Which statement is best supported by the passage?
- The Amazon will be completely destroyed within the next decade.
- Deforestation of the Amazon poses serious risks to global biodiversity and atmospheric oxygen. (Correct answer)
- Replanting trees can fully reverse the damage caused by deforestation.
- The Amazon only matters to countries in South America.
Correct answer: Deforestation of the Amazon poses serious risks to global biodiversity and atmospheric oxygen.
The passage establishes the Amazon's global significance (oxygen, biodiversity) and then links deforestation to the risk of irreversible damage, supporting this conclusion.
Question 15: Read: 'The Dust Bowl of the 1930s was caused by a combination of severe drought and years of intensive farming that had stripped the plains of natural grasses. When the drought hit, there was nothing to hold the topsoil in place, and massive dust storms blackened skies from Texas to Canada.' Which two factors does the passage identify as causes of the Dust Bowl?
- Overgrazing by livestock and industrial pollution
- Severe drought and farming practices that removed natural ground cover (Correct answer)
- Government agricultural policies and lack of irrigation systems
- High winds from Canada and poor crop rotation techniques
Correct answer: Severe drought and farming practices that removed natural ground cover
The passage explicitly states that drought and intensive farming that stripped natural grasses together caused the Dust Bowl.
Question 16: A passage on antibiotic resistance states: 'Bacteria evolve rapidly, and overuse of antibiotics accelerates the selection of resistant strains. Each year, antibiotic-resistant infections kill approximately 700,000 people globally.' What is the most logical conclusion a reader can draw?
- Antibiotics should be banned from medical use immediately.
- Antibiotic resistance is a growing public health crisis linked to overuse of these drugs. (Correct answer)
- Bacteria are becoming immune to all medicines, not just antibiotics.
- 700,000 people died because doctors refused to prescribe antibiotics.
Correct answer: Antibiotic resistance is a growing public health crisis linked to overuse of these drugs.
The passage links overuse to accelerated resistance and then cites mortality figures, logically supporting the conclusion that antibiotic resistance is a serious, growing health crisis.
Question 17: Read the following: 'First, the researcher collected water samples from three sites. Next, each sample was tested for pH, nitrate levels, and bacterial content. Finally, the results were compared against EPA safety standards.' What is the main purpose of this passage?
- To argue that water in the studied area is unsafe to drink
- To explain the step-by-step procedure used to test water quality (Correct answer)
- To summarize the findings of a water quality study
- To compare the EPA standards to international water regulations
Correct answer: To explain the step-by-step procedure used to test water quality
The sequential structure (first, next, finally) and procedural language indicate the passage is describing a process, not presenting results or arguments.
Question 18: Passage: 'Marie Curie became the first person to win Nobel Prizes in two different sciences — physics in 1903 and chemistry in 1911. She faced significant discrimination as a woman in a male-dominated field yet continued her research until her death.' What inference is most strongly supported?
- Curie's achievements were primarily due to her wealthy background.
- Curie's scientific contributions were exceptional despite significant institutional barriers. (Correct answer)
- The Nobel committee preferred to award women scientists in the early 1900s.
- Physics and chemistry were considered equally important sciences in Curie's era.
Correct answer: Curie's scientific contributions were exceptional despite significant institutional barriers.
The passage highlights both her unprecedented dual Nobel achievement and the discrimination she overcame, supporting the inference that her work was remarkable despite obstacles.
Question 19: A student reads: 'Honey never spoils. Archaeologists have found 3,000-year-old honey in Egyptian tombs that was still edible. Honey's low moisture content and natural hydrogen peroxide prevent bacterial growth.' Which sentence provides the best explanation for why honey doesn't spoil?
- Honey never spoils.
- Archaeologists have found 3,000-year-old honey in Egyptian tombs that was still edible.
- Honey's low moisture content and natural hydrogen peroxide prevent bacterial growth. (Correct answer)
- Ancient Egyptians stored honey in sealed containers.
Correct answer: Honey's low moisture content and natural hydrogen peroxide prevent bacterial growth.
The third sentence provides the scientific mechanism — low moisture and hydrogen peroxide preventing bacterial growth — which explains why honey is resistant to spoilage.
Question 20: Read: 'While social media connects people across distances, it also contributes to increased rates of anxiety and depression among teenagers, according to multiple studies. Researchers note that time spent on comparison-heavy platforms correlates with lower self-esteem.' What is the author most likely trying to convey?
- Teenagers should be banned from all social media platforms.
- Social media has a complex impact that includes documented psychological harms, especially for young users. (Correct answer)
- Social media is purely harmful and offers no benefits to anyone.
- The research on social media and mental health is still too limited to draw any conclusions.
Correct answer: Social media has a complex impact that includes documented psychological harms, especially for young users.
The passage acknowledges social media's connecting benefit but focuses on research-backed harms for teenagers, suggesting a nuanced view of its complex impact.
Question 21: Passage: 'The wolf population in Yellowstone was reintroduced in 1995 after a 70-year absence. Wolves preyed on elk, which had been overgrazing riverbanks. With fewer elk in those areas, vegetation recovered, which stabilized stream banks and changed river flow patterns. This cascade is called a trophic cascade.' According to the passage, what was the sequence of events following wolf reintroduction?
- Rivers changed → vegetation recovered → elk population declined
- Wolves reintroduced → elk overgrazing reduced → vegetation recovered → rivers changed (Correct answer)
- Vegetation declined → wolves were reintroduced → elk moved away
- Wolves reintroduced → river banks collapsed → elk migrated south
Correct answer: Wolves reintroduced → elk overgrazing reduced → vegetation recovered → rivers changed
The passage explicitly traces this chain: wolves reduced elk grazing → vegetation recovered → stream banks stabilized → river flow changed.
Core Academic Skills Assessment Reading: Key Ideas and Details
Read the passage: 'Photosynthesis converts light energy into chemical energy stored in glucose.
Chloroplasts, found in plant cells, contain chlorophyll that absorbs sunlight.
Water and carbon dioxide are the raw materials, while oxygen is released as a byproduct.' Which sentence best states the central idea?
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