8. Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the questions.
There are two types of diabetes, insulin-dependent and non-insulin-dependent. Between 90-95% of the estimated 13-14 million people in the United States with diabetes have non-insulin-dependent, or Type II, diabetes. Because this form of diabetes usually begins in adults over the age of 40 and is most common after the age of 55, it used to be called adult-onset diabetes. Its symptoms often develop gradually and are hard to identify at first; therefore, nearly half of all people with diabetes do not know they have it. For instance, someone who has developed Type II diabetes may feel tired or ill without knowing why. This can be particularly dangerous because untreated diabetes can cause damage to the heart, blood vessels, eyes, kidneys, and nerves. While the causes, short-term effects, and treatments of the two types of diabetes differ, both types can cause the same long-term health problems.
Most importantly, both types affect the body's ability to use digested food for energy. Diabetes does not interfere with digestion but it does prevent the body from using an important product of digestion, glucose (commonly known as sugar) for energy. After a meal, the normal digestive system breaks some food down into glucose. The blood carries the glucose or sugar throughout the body, causing blood glucose levels to rise. In response to this rise, the hormone insulin is released into the bloodstream and signals the body tissues to metabolize or burn the glucose for fuel, which causes blood glucose levels to return to normal. The glucose that the body does not used right away in stored in the liver, muscle or fat.
In both types of diabetes, however, this normal process malfunctions. A gland called the pancreas, found just behind the stomach, makes insulin. In people with insulin-dependent diabetes, the pancreas does not produce insulin at all. This condition usually begins in childhood and is known as Type I (formerly called juvenile-onset) diabetes. These patients must have daily insulin injections to survive. People with non-insulin-dependent diabetes usually produce some insulin in their pancreas, but their bodies' tissues do not respond well to the insulin signal and, therefore, do not metabolize the glucose properly, a condition known as insulin resistance.
Insulin resistance is an important factor in non-insulin-dependent diabetes, and scientists are searching for the causes of insulin resistance. They have identified two possibilities. The first is that there could be a defect in the insulin receptors on cells. Like an appliance that needs to be plugged into an electrical outlet, insulin has to bind to a receptor in order to function. Several things can go wrong with receptors. For example, there may not be enough receptors to which insulin may bind, or a defect in the receptors may prevent insulin from binding. The second possible cause of insulin resistance is that, although insulin may bind to the receptors, the cells do not read the signal to metabolize the glucose. Scientists continue to study these cells to see why this might happen.
There's no cure for diabetes yet. However, there are ways to alleviate its symptoms. In 1986, a National Institute of Health panel of experts recommended that the best treatment for non-insulin-dependent diabetes is a diet that helps one maintain a normal weight and pays particular attention to a proper balance of the different food groups. Many experts, including those in the American Diabetes Association, recommend that 50-60% of daily calories come from carbohydrates, 12-20% from protein, and no more than 30% from fat. Foods that are rich in carbohydrates, like breads, cereals, fruits, and vegetables, break down into glucose during digestion, causing blood glucose to rise. Additionally, studies have shown that cooked foods raise blood glucose higher than raw, unpeeled foods. A doctor or nutritionist should always be consulted for more of this kind of information and for help in planning a diet to offset the effects of this form of diabetes.
8.1. According to the passage, what may be the most dangerous aspect of Type II diabetes?
8.2. Which of the following are the same for Type I and Type II diabetes?
8.3. According to the passage, one place in which excess glucose is stored in the ……..
8.4. A diet dominated by which of the following is recommended for non-insulin-dependent diabetics?
8.5. Which of the following is the main function of insulin?
8.6. Which of the following statements best summaries the main theme of the passage?
8.7. Which of the following is mentioned in the passage as a possible problem with insulin receptors in insulin-resistant individuals?
8.8. According to the passage, in normal individuals, which of the following processes occur immediately after the digestive system converts some food into glucose?
8.9. Based on the information in the passage, which of the following best describes people with Type I diabetes?
