Text A

The Nutrients in Food

　　Nutrients are the parts of food that are important for life and health. Nutrients are important for three reasons. First, some nutrients provide fuel for energy. Second, some nutrients build and repair body tissues. Third, some nutrients help control different processes of the body like the absorption of minerals and the clotting of blood. Scientists think there are 40 to 50 nutrients. These nutrients are divided into five general groups: carbohydrates, fats, proteins, minerals and vitamins.

　　The first group of nutrients is carbohydrates. These are two kinds of carbohydrates: starches and sugars. Bread, potatoes, and rice are starches. They have many carbohydrates. Candy, soft drinks, jelly, and other foods with sugar also have carbohydrates. Carbohydrates are important because they provide the body with heat and energy. Sugar, for instance, is 100 percent energy. It has no other food value. Sugar does not build body tissues or control body processes. If there are too many carbohydrates in the body, there are stored as body fat. The body stores fuel as fat.

　　There are two types of fat: animal and vegetable. Butter, cream, and the fat in bacon are animal fats. Olive oil, corn oil, and peanut oil are vegetable fat. The body has fat under the skin and around some of the organs inside. The average adult has 10 to 11 kilograms( 20 to 25 pounds) of body fat. If adults eat too many carbohydrates and fats, they can add another 45 kilograms(100 pounds) to their bodies. Fat is extra fuel. When the body needs energy, it changes the fat into carbohydrates. The carbohydrates are used for energy. Fat also keeps the body warm.

　　The third group of nutrients is proteins. The word “ protein” comes from a Greek word that means “ of first importance.” Proteins are made of amino acids which build and repair body tissues. They are an important part of all the muscles, organs, skin, and hair. The body has 22 different amino acids. Nutritionists call eight of these amino acids because the body does not manufacture them.

　　There are two kinds of proteins: complete proteins and incomplete proteins. Complete proteins, which the body needs for growth, have all the essential amino acids. Meat, fish, poultry, eggs, milk, and cheese have complete proteins. The body needs complete proteins every day. Incomplete proteins do not have all the essential amino acids. The protein in vegetables and grains, for instance, are incomplete proteins. Two ways to form complete proteins from incomplete proteins are: 1. to mix vegetables and grains correctly, or 2. to add a small amount of meat or milk to a large amount of grains. The body can then use the complete proteins which result from the mixtures.

　　Extra protein in the body can be changed to fat and stored as body fat. It can also be changed to carbohydrates and used for energy. If people do not eat enough carbohydrates and fats for the energy that they need, their body uses proteins for energy. Then the body does not have the proteins that it needs to build and repair tissues. A nutritious diet includes carbohydrates and fats for energy, and proteins for growth.

　　The fourth group of nutrients is minerals. More than twenty different minerals are in the body. Three of the most important minerals are calcium, phosphorus, and iron. Calcium and phosphorus work together. The bones and the teeth have 99 percent of the calcium in the body. If people have enough calcium and phosphorus, their bones and teeth will be strong and hard. In addition, their muscles, nerves, and heart will work correctly. Milk and hard cheeses are the best sources of calcium. After the age of 19, people need 400 to 500 milligrams of calcium a day. People who do not drink three glasses of milk daily can eat 50 hamburgers or 56 apples to get the calcium they need.

　　Iron is the mineral that makes blood look red. All lean meats have iron; liver is an especially good source of iron. Whole grains, nuts, some vegetables, and dried fruits also have iron. If there is not enough iron in their dies, people will get a disease that is commonly called anemia. Anemia is found all over the world. People with anemia do not have enough in their blood. Because iron carries oxygen, people who do not have enough iron do not get enough oxygen for their normal activities. Their hearts beat faster so their bodies can get more oxygen. People who have anemia often get tired easily. Sometimes their skin looks white: it does not look pink and healthy.

　　Nutritionists think there are thirteen vitamins that humans need. Vitamins are important because they prevent diseases and help control body processes. Vitamin A is important for healthy skin and eyes. People who do not have enough vitamin A may have night blindness. Some automobile accidents happen in the evening because people who lack vitamin A do not see the road well after they look at the bright headlights of a car. Vitamin A in the diet comes from deep yellow fruits and vegetables, dark green leafy vegetables, and whole milk.

　　When people have enough B vitamins, their appetite is good and their nerves are calm. B vitamins in the diet come from some meats and vegetables, milk, cottage cheese, and whole grains. When a grain is processed, it loses vitamins. For example, there is a big difference between brown and white rice. When rice is processed, the brown outside of rice has an important B vitamin which white rice lacks. In short, brown rice has more B vitamins than processed rice.

　　Vitamin C keeps the cells of the body together. It helps skin tissue recover from cuts and burns. Vitamin C in the diet comes from tomatoes, citrus fruits like lemons and oranges, and some vegetables such as cabbage and green peppers.

　　Vitamin D is called the “sunshine” vitamin. When people sit outside, ultraviolet rays from the sun change a fat in their skin to vitamin D. vitamin D is also in cod liver oil and the yellow of eggs. It is sometimes added to milk. Vitamin D helps the body absorb calcium. It helps build strong bones, and it prevents a disease in children that is called rickets. When children have this disease, their bones bend because they do not become hard. Rickets is seldom found in sunny, tropical countries. Rickets is more common in countries that have long winters with little sunshine, in cities that have pollution that keeps the sun out, and in towns surrounded by mountains that keep the sun out.

　　There is no one food that is essential, but there are nutrients that are necessary for good health. If people want to be healthy and active, they need to get all the essential nutrients. A healthy body needs carbohydrates, fats, proteins, minerals, and vitamins.

Text B

History of Basketball

　　Dr. James Naismith is known world-wide as the inventor of basketball. He was born in 1861 in Ramsay township, near Almonte , Ontario , Canada . The concept of basketball was born from Naismith's school days in the area where he played a simple child's game known as duck-on-a-rock outside his one-room schoolhouse. The game involved attempting to knock a "duck" off the top of a large rock by tossing another rock at it. Naismith went on to attend McGill University in Montreal , Quebec , Canada .

　　After serving as McGill's Athletic Director, James Naismith moved on to the YMCA Training School in Springfield , Massachusetts , USA in 1891, where the sport of basketball was born. In Springfield , Naismith was faced with the problem of finding a sport that was suitable for play inside during the Massachusetts winter for the students at the School for Christian Workers. Naismith wanted to create a game of skill for the students instead of one that relied solely on strength. He needed a game that could be played indoors in a relatively small space. The first game was played with a soccer ball and two peach baskets used as goals. Naismith joined the University of Kansas faculty in 1898, teaching physical education and being a chaplain.

　　In addition to the creation of the basketball, James Naismith graduated as a medical doctor, primarily interested in sports physiology and what we would today call sports science and as Presbyterian minister, with a keen interest in philosophy and clean living. Naismith watched his sport, basketball, introduced in many nations by the YMCA movement as early as 1893. Basketball was introduced at the Berlin Olympics in 1936. Naismith was flown to Berlin to watch the games. He died in Lawrence , Kansas , in 1939.

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