During the summer you should be even more careful than usual of the foods you prepare. Foods spoil faster in hot weather than in cold weather. When you are shopping, purchase frozen and refrigerated food last. Don’t make long stops on the way home, because frozen foods could be soft or warm. Using insulated bags helps keep food cold until you can get home. Milk and milk products should be refrigerated immediately. When camping or picnicking, or at any time when refrigeration isn’t available, use special dry food. Don’t leave foods in a hot car or beach bag. Picnic favorites like meat，chicken, and egg salad should be kept in a cooler. Above all, if a food doesn’t seem to be normal in smell or appearance, throw it away immediately. Don’t taste it.
When should you be even more careful than usual of the foods （）| Most growing plants contain much more
water than all other materials combined. C. R. Barnes has suggested that it is
as proper to term the plant a water structure as to call a house composed mainly
of brick a brick building. Certain it is that all essential processes of plant
growth and development occur in water. The mineral elements from the soil that
are usable by the plant must be dissolved in the soil solution before they can
be taken into the root. They are carried to all parts of the growing plant and
are built into essential plant materials while in a dissolved state. The carbon
dioxide from the air may enter the leaf as a gas but is dissolved in water in
the leaf before it is combined with a part of the water to form simple
sugars—the base material from which the plant body is mainly built. Actively
growing plant parts are generally 75 to 90 perce A. (A) forming sugars B. (B) sustaining woody stems C. (C) keeping green D. (D) producing carbon dioxide 我来回答: 提交
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