Which of the following plant structures are specialized for the absorption of water and nutrients from the environment?
- A. Roots
- B. Leaves
- C. Flowers
- D. Stems
Correct Answer & Rationale
Correct Answer: A
Roots are specialized structures designed for the absorption of water and nutrients from the soil, featuring a large surface area and root hairs that enhance their efficiency. Leaves primarily function in photosynthesis and gas exchange, not nutrient absorption. Flowers are reproductive structures that facilitate pollination and seed production, playing no direct role in nutrient uptake. Stems support the plant and transport water and nutrients between roots and leaves, but they do not absorb them. Thus, roots are uniquely equipped for this essential task.
Roots are specialized structures designed for the absorption of water and nutrients from the soil, featuring a large surface area and root hairs that enhance their efficiency. Leaves primarily function in photosynthesis and gas exchange, not nutrient absorption. Flowers are reproductive structures that facilitate pollination and seed production, playing no direct role in nutrient uptake. Stems support the plant and transport water and nutrients between roots and leaves, but they do not absorb them. Thus, roots are uniquely equipped for this essential task.
Other Related Questions
The preceding figure represents a cloud that has formed in the atmosphere above Earth's surface. Which of the following diagrams best illustrates the arrangement of charges in the cloud and on Earth's surface just before a cloud-to-ground lightning strike?
- A. Cloud: top (+), middle (-), bottom (+); Ground: (-)
- B. Cloud: top (+), middle (+), bottom (-); Ground: (+)
- C. Cloud: top (-), middle (+), bottom (+); Ground: (-)
- D. Cloud: top (+), middle (-), bottom (-); Ground: (+)
Correct Answer & Rationale
Correct Answer: D
In a thunderstorm, clouds typically develop a charge separation where the upper region becomes positively charged and the lower region negatively charged. This charge distribution is crucial for lightning formation. Option D accurately represents this arrangement: the top of the cloud is positively charged, the middle is negatively charged, and the bottom is also negatively charged, while the ground becomes positively charged in response to the cloud's negative charge. Option A incorrectly places a positive charge at the bottom of the cloud, which does not align with typical charge distributions. Option B misrepresents the charges by having two positive regions in the cloud, which is unlikely. Option C also fails by placing the top of the cloud negatively charged, contradicting the established understanding of charge distribution in storm clouds.
In a thunderstorm, clouds typically develop a charge separation where the upper region becomes positively charged and the lower region negatively charged. This charge distribution is crucial for lightning formation. Option D accurately represents this arrangement: the top of the cloud is positively charged, the middle is negatively charged, and the bottom is also negatively charged, while the ground becomes positively charged in response to the cloud's negative charge. Option A incorrectly places a positive charge at the bottom of the cloud, which does not align with typical charge distributions. Option B misrepresents the charges by having two positive regions in the cloud, which is unlikely. Option C also fails by placing the top of the cloud negatively charged, contradicting the established understanding of charge distribution in storm clouds.
Which THREE of the following are health problems associated with long-term exposure to air pollution?
- A. Accelerated aging of the lungs
- B. Increased lung capacity
- C. Increased risk of asthma
- D. Increased risk of cardiovascular disease
Correct Answer & Rationale
Correct Answer: A,C,D
Long-term exposure to air pollution can lead to several significant health issues. Option A, accelerated aging of the lungs, is accurate as pollutants can damage lung tissue over time, reducing function. Option C is also correct; exposure to air pollution is linked to a higher incidence of asthma, particularly in children, due to airway inflammation and increased sensitivity. Option D is valid as well; numerous studies show that air pollution significantly raises the risk of cardiovascular diseases due to systemic inflammation and oxidative stress. Conversely, Option B, increased lung capacity, is incorrect. Air pollution typically impairs lung function rather than enhancing it, leading to reduced capacity over time.
Long-term exposure to air pollution can lead to several significant health issues. Option A, accelerated aging of the lungs, is accurate as pollutants can damage lung tissue over time, reducing function. Option C is also correct; exposure to air pollution is linked to a higher incidence of asthma, particularly in children, due to airway inflammation and increased sensitivity. Option D is valid as well; numerous studies show that air pollution significantly raises the risk of cardiovascular diseases due to systemic inflammation and oxidative stress. Conversely, Option B, increased lung capacity, is incorrect. Air pollution typically impairs lung function rather than enhancing it, leading to reduced capacity over time.
Which of the following best describes what happens when two magnets repel each other?
- A. The objects are pulled toward one another.
- B. The objects are pushed away from one another.
- C. An electric spark jumps from one object to another.
- D. Nothing happens until the objects are touched.
Correct Answer & Rationale
Correct Answer: B
When two magnets repel each other, they exert forces that push away from one another due to their like poles (north-north or south-south). This repulsion is a fundamental property of magnetism. Option A is incorrect because it describes attraction, which occurs when opposite poles (north-south) interact. Option C is misleading; electric sparks are not a typical result of magnet repulsion. Option D is also wrong, as repulsion occurs before any physical contact, demonstrating the active interaction between the magnets. Thus, the best description of this phenomenon is that the objects are pushed away from one another.
When two magnets repel each other, they exert forces that push away from one another due to their like poles (north-north or south-south). This repulsion is a fundamental property of magnetism. Option A is incorrect because it describes attraction, which occurs when opposite poles (north-south) interact. Option C is misleading; electric sparks are not a typical result of magnet repulsion. Option D is also wrong, as repulsion occurs before any physical contact, demonstrating the active interaction between the magnets. Thus, the best description of this phenomenon is that the objects are pushed away from one another.
Earth's diameter is approximately 12,700 kilometers. Which of the following layers is located approximately 6,000 kilometers beneath Earth's surface and is composed primarily of iron and nickel?
- A. The core
- B. The crust
- C. The lithosphere
- D. The mantle
Correct Answer & Rationale
Correct Answer: A
The core, located about 6,000 kilometers beneath Earth's surface, is primarily composed of iron and nickel, making it the densest layer of the planet. The crust, option B, is the outermost layer and is much shallower, averaging only about 30 kilometers thick. Option C, the lithosphere, includes the crust and the uppermost part of the mantle, but it does not reach anywhere near 6,000 kilometers deep. The mantle, option D, lies between the crust and the core, extending to about 2,900 kilometers down, but it is primarily composed of silicate minerals, not iron and nickel.
The core, located about 6,000 kilometers beneath Earth's surface, is primarily composed of iron and nickel, making it the densest layer of the planet. The crust, option B, is the outermost layer and is much shallower, averaging only about 30 kilometers thick. Option C, the lithosphere, includes the crust and the uppermost part of the mantle, but it does not reach anywhere near 6,000 kilometers deep. The mantle, option D, lies between the crust and the core, extending to about 2,900 kilometers down, but it is primarily composed of silicate minerals, not iron and nickel.