praxis elementary science 5005 practice test

A series of tests developed by ETS to assess the skills and knowledge of prospective teachers.

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.

Other Related Questions

Which TWO of the following are true statements about hurricanes?
  • A. They are typically over 160 kilometers, or 100 miles, in diameter.
  • B. They form over cold water in Earth's polar regions and move slowly.
  • C. They develop quickly and usually last for less than 30 minutes.
  • D. They can have sustained wind speeds that are over 200 kilometers per hour.
Correct Answer & Rationale
Correct Answer: A, D

Hurricanes are vast systems, often exceeding 160 kilometers (100 miles) in diameter, making option A true. Additionally, they can reach sustained wind speeds over 200 kilometers per hour, confirming option D. In contrast, option B is incorrect as hurricanes form over warm waters, typically in tropical regions, not cold polar waters. Moreover, they do not move slowly; they can travel at significant speeds. Option C is also false; while hurricanes can develop rapidly, they generally last for several days, not just 30 minutes. Understanding these characteristics is crucial for recognizing the nature and impact of hurricanes.
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.
Of the following gases, which is found in the atmosphere in the greatest concentration?
  • A. O2
  • B. N2
  • C. H2
  • D. CO2
Correct Answer & Rationale
Correct Answer: B

Nitrogen (N2) constitutes about 78% of the Earth's atmosphere, making it the most abundant gas. Oxygen (O2), while essential for life, is present at around 21%, significantly less than nitrogen. Hydrogen (H2) is found in trace amounts and is not a major component of the atmosphere. Carbon dioxide (CO2) is also present in much smaller concentrations, approximately 0.04%, and is primarily significant for its role in climate regulation. Therefore, nitrogen is the predominant gas, while the others are present in much lower concentrations.
Which of the following best describes a comet?
  • A. A small planet orbiting the Sun between Mars and Jupiter.
  • B. A chunk composed primarily of metal that enters Earth's atmosphere.
  • C. A chunk composed primarily of rock, ice, and dust orbiting the Sun in an elliptical path.
  • D. A dark region that appears periodically on the surface of the Sun.
Correct Answer & Rationale
Correct Answer: C

Option C accurately describes a comet as a chunk composed primarily of rock, ice, and dust that orbits the Sun in an elliptical path. This definition captures the essential components and behavior of comets. Option A incorrectly defines a comet as a small planet, which is misleading; comets are distinct from asteroids and do not have the same characteristics. Option B describes a meteoroid, which is a metallic chunk entering Earth's atmosphere, not a comet. Option D refers to sunspots, which are dark regions on the Sun's surface, unrelated to comets. Each incorrect option misrepresents the nature of comets, highlighting the unique characteristics of these celestial bodies.