Antioxidants play an important role in the preservation of food. Which one of the following statements best describes how antioxidants prevent fat from turning rancid?
Antioxidants neutralize free radicals that would turn fats rancid.
B. Antioxidants donate electrons to fat, preventing the fat from going bad.
C. Antioxidants pick up electrons from fat, preventing the fat from going bad.
D. Antioxidants kill bacteria that produce free radicals by osmosis.
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What is the most important characteristic a sweetener must have in order to act as an effective sugar substitute?
A. It must substitute in equal weight and volumes for sugar in recipes.
B. It must not be digested nor absorbed in the upper portion of the intestine known as the small intestine.
C. It must be similar in chemical structure to sucrose to interact with the sweet receptors on the tongue.
D. It must be resistant to degradation at high cooking temperature so it can be used in baked goods.
Opponents to genetically modified foods encourage scientist and policy makers to apply the precautionary principle to the approval of new products. What does this principle require?
A. Research shows that the benefits outweigh the risks associated with the product.
B. Tests on rodents have shown that the products are not a carcinogen.
C. Research has demonstrated proof of no harm before products are approved.
D. The facilities that manufacture the product have been inspected and are certified.
The tobacco plant produces a toxic compound known as nicotine. Select the statement that best describes the function nicotine serves in the plant.
A. There is no function for the plant; scientists genetically engineered the plant to produce nicotine.
B. Nicotine protects the plant from insects that try eating it.
C. Nicotine allows the plant to grow in dry soil conditions.
D. Nicotine increases photosynthesis in tobacco plants.
Name the substance used to kill, repel, or control certain forms of plant, fungal or animal life that are considered to be unwanted. ______
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