CAEC Science Practice test

Which of the following claims about a new sustainable farming method cannot be tested through scientific inquiry?

A) The method increases crop yields by 20% compared to traditional farming methods.
B) The method reduces water consumption by 30%.
C) The method improves the ethical treatment of farmworkers.
D) The method lowers the use of chemical fertilizers by 40%

Which of the following sources of information is likely to be the most objective and unbiased about the health effects of different types of sugar?

A) A brochure from a sugar cane farmers’ cooperative discussing the benefits of natural sugar.
B) A research study funded by a major artificial sweetener company comparing the health effects of artificial sweeteners and sugar.
C) A report from a government health agency summarizing the results of multiple independent studies on the health effects of various sugars.
D) A social media post from a popular health blogger promoting the use of honey as a natural sugar alternative.

A scientist monitors the pH of soil to ensure it supports plant growth. The optimal pH range for most plants is 6.0 to 7.5. After performing a drop test on a soil water extract, the sample turns red.

The pH of the soil is:

A) 8.4
B) 7.2
C) 7.8
D) 6.2

The insecticide DDT was developed in the 1940s to combat diseases like malaria by killing mosquitoes. However, scientists discovered that DDT biomagnifies, meaning it accumulates in higher concentrations as it moves through the food chain, leading to environmental damage, such as predatory birds producing weak eggshells.

The use of DDT caused widespread environmental problems due to its persistence and biomagnification.

Which of the following strategies would best reduce the risks of similar issues with other pesticides?

A) Use pesticides only in small, controlled amounts.
B) Ban pesticides with long environmental persistence and high toxicity.
C) Focus on public awareness campaigns about pesticide use.
D) Replace pesticides with biological pest control methods like introducing predators.

Researchers are comparing the growth of plants using three different fertilizers: Organic, Synthetic, and No Fertilizer.

• Organic fertilizer: Made from natural substances, is believed to improve soil health.
• Synthetic fertilizer: Chemically manufactured and tends to show quicker results.
• No fertilizer: Acts as the control group to compare the effect of fertilizers.

The researchers planted 50 identical seeds for each fertilizer type in identical pots and monitored growth over six weeks.

Which of the following actions would most likely reduce bias in this study?

A) Watering the plants with different amounts of water depending on fertilizer type.
B) Measuring plant height at random intervals during the six weeks.
C) Placing all the pots in a single greenhouse with identical environmental conditions.
D) Allowing the researchers to know which fertilizer was used for each plant group during the study.

Which plant recovered more significantly in height after the drought period (2015–2020)?

A) Plant A (Oak Tree)
B) Plant B (Willow Tree)
C) Both recovered similarly
D) Neither recovered significantly