"Cure for Concrete" vs. "Persevering Plants"

Which characteristic of geothermal vents made the survival of nearby plants so surprising? (Plants)

• The depth of the holes.

• The heat they generate

• The number of them that exist

• The amount of pressure they release

Answer explanation

The survival of nearby plants is surprising due to the heat generated by geothermal vents, as most plants cannot thrive in such extreme temperatures. This unique adaptation highlights the resilience of certain plant species.

How do the photograph and caption after paragraph 4 help the reader better understand the selection? (Plants)

• They explain how endophytes work to help plants.

• They demonstrate the effect endophytes can have on plants.

• They illustrate what kinds of plants endophytes can help.

• The show the conditions against which endophytes can protect plants.

Answer explanation

The photograph and caption illustrate the positive impact of endophytes on plants, showing how they enhance growth and resilience, which helps the reader understand their significance in plant health.

How are paragraphs 2 through 4 organized? (Plants)

• They compare the plants Rodriguez collected to the endophytes living on the plants.

• The describe the steps Rodriguez followed while researching plants in his laboratory.

• They explain the problem Rodriguez was trying to solve based on his observations.

• The describe the structure of the plants Rodriguez collected from a harsh environment.

Answer explanation

Paragraphs 2 through 4 focus on the problem Rodriguez aimed to address, detailing his observations that led to his research on plants, making this choice the correct answer.

What is paragraph 1 mainly about? (Plants)

• The unusual conditions in which some plants can survive.

• The occurrence of geothermal vents in several western states.

• The way geothermal vents release pressure in the form of steam.

• The types of plants microbiologists have observed at a national park.

Answer explanation

Paragraph 1 discusses the unusual conditions that allow certain plants to thrive, highlighting their unique survival mechanisms in extreme environments.

An idea emphasized throughout the selection is that Rodriguez's endophyte solution - (Plants)

• can improve plant life in national parks

• eliminates the need to water plants regularly

• will allow farmers to plant crops regardless of the season

• can restore a plant's natural resistance to the effects of a harsh climate

Answer explanation

Rodriguez's endophyte solution enhances plants' natural resistance, enabling them to better withstand harsh climates, which is crucial for their survival and growth in challenging environmental conditions.

Which statement best expresses the main idea of paragraph 3? (Concrete)

• Modern highways and bridges are often constructed with concrete.

• Concrete was used by ancient Romans to build massive structures.

• The demand for concrete has doubled in the last decade.

• Concrete has been and continues to be an important building material.

Answer explanation

The correct choice highlights the enduring significance of concrete as a building material, reflecting its historical use and ongoing relevance, which aligns with the main idea of paragraph 3.

The information in paragraph 6 helps the reader understand that bioconcrete - (Concrete)

• works best in areas affected by harsh weather conditions

• is effective in repairing water damage

• has a maximum weight it can support

• is limited to use in certain parts of the world

Answer explanation

The information in paragraph 6 indicates that bioconcrete is designed to repair water damage, making it effective in restoring structures affected by moisture, which aligns with the correct answer.

How does the author organize paragraph 1? (Concrete)

• By listing types of bacteria and then telling how they help fight diseases in the human body

• By defining bacteria and then explaining how bacteria are used in some products

• By stating a popular belief about bacteria and then disproving with examples

• By comparing good and bad bacteria and then describing how bacteria work

Answer explanation

The author begins by addressing a common misconception about bacteria, then provides examples to counter this belief, effectively disproving it. This structure highlights the contrast between popular beliefs and factual information.

What is the best summary of the article? (Concrete)

• Concrete is a popular material, but it can develop cracks over time. Microbiologist Hendrik Jonkers believes that adding bacteria to concrete can help remedy this problem and provide savings for the construction industry.

• Hendrik Jonkers, a Dutch microbiologist, noticed that concrete cracks over time. He decided to add bacteria to concrete to make a substance called bioconcrete. The bacteria are placed inside plastic capsules that are mixed into wet concrete.

• A Dutch microbiologist named Hendrik Jonkers became interested in investigating how bacteria might be applied to concrete to fill cracks in concrete caused by water. He developed a self-healing concrete bioconcrete that works to make concrete more durable.

• Microbiologist Hendrik Jonkers wondered if concrete could repair itself in the same way that human bones do. He developed bioconcrete, which was used to build a lifeguard station near a lake in the Netherlands and repair an irrigation system in Ecuador.

Answer explanation

The correct choice summarizes Hendrik Jonkers' development of bioconcrete, highlighting its purpose of using bacteria to fill cracks and enhance durability, which aligns with the article's focus on self-healing concrete.

Read this sentence from paragraph 2.

"When a bone breaks in the human body, it is able to repair itself."

What is most likely the reason the author includes this information?

(Concrete)

• To advocate for more research concerning skeletal injuries.

• To suggest bacteria could improve people's health.

• To show the need for Jonkers' research.

• To provide an example of the goal of Jonkers' research.

Answer explanation

The author includes this information to illustrate the goal of Jonkers' research, which likely focuses on understanding and enhancing the body's natural ability to heal, as exemplified by the self-repair of broken bones.