Task1. Fill in the gaps using the words in the box.
tissues; average; decrease; animals; molecules; proteins; building; nitrogen;
body
1. All our foodstuffs - fats, starches, sugars, and_ contain the elements of
carbon, hydrogen, and oxygen in varying proportions. 2. Most plants make their
own protein by combining the _from nitrogen-containing materials in the
the proteins. 4. We must get our proteins
soil with carbon dioxide from the air and with water. 3. Animals and people cannot
use such simple raw materials for
from plants and other_
5. Next to water, protein is the most plentiful sub-
stance in the
6. The proteins in the body_ are not there as fixed,
unchanging substances deposited for a life-time. 7. Some or parts of molecules
always are breaking down and others are being built as replacements.
8. The total daily protein needs increase steadily from birth to adolescence and
then_ ____________to a maintenance level for adulthood. 9. The recommended daily
protein allowances for adults are 70 grams for the average man who weighs about
154 pounds, and 58 grams for the_ woman who weighs 128 pounds.