In most cases, primary food production occurs in a process called photosynthesis, which is powered by sunlight. In a few environments, primary production happens though a process called chemosynthesis, which runs on chemical energy. Together, photosynthesis and chemosynthesis fuel all life on Earth.
Eat 5 â 7 servings of meat and beans per day. This depends on the total number of calories you consume in a day. 1  If you consume 1600 â 1800 calories, eat 5 servings per day. 2  If you consume 2000 calories, eat 5 Â½ servings per day. 3  If you consume 2200 calories, eat 6 servings per day. 4  If you consume 2400 â 2600 calories, eat 6 Â½ servings per day.
Women under the age of 50 need 6 ounces of grains each day, and at least 3 of them should be whole. After age 50, women should eat 5 ounces of grains a day, and 2 1/2 ounces should be whole grains. Men under the age of 30 need 8 ounces a day, at least 4 ounces being whole. Between the ages of 31 and 50, men need 7 ounces of grain foods each day, with at least 3 1/2 ounces being whole.