Chapter 4 Study Questions

20. What percentage of daily energy intake should come from carbohydrates

45-65%

1. Describe the structure of a monosaccharide and name the three monosaccharides important in nutrition. Name three disaccharides commonly found in foods and their component monosaccharides. In what foods are these sugars found?

A carbohydrate with a general structure of a ring composed of carbon, hydrogen and oxygen atoms. Monosaccharides important in nutrition are glucose, fructose, and galactose; disaccharides important in nutrition are sucrose (fructose + glucose), lactose (galactose + glucose), and maltose (2 glucose). Nearly all plant foods contain glucose; most plants (especially fruits and saps) contain fructose; galactose is not found as such in foods; sucrose occurs in many fruits and some vegetables and grains; lactose is found in milk; maltose is found in seeds.

2. What happens in a condensation reaction? In a hydrolysis reaction?

Condensation combines two reactants to yield one product with the removal of water; hydrolysis splits one reactant into two products with the addition of water

15. What are the health effects of sugars? What are the dietary recommendations regarding concentrated sugar intake?

Excess sugar can cause malnutrition if sugar displaces needed nutrients from the diet. It can contribute to obesity. Excess sugar can contribute to elevated blood lipids, and it can cause dental caries. Less than 10% of total kcalories should come from concentrated sugar.

18. What foods provide starches and fiber'

Fruits, vegetables, legumes, whole-grain breads and cereals.

18. What foods provide starches and fiber's

Fruits, vegetables, legumes, whole-grain breads and cereals.

11. How does the body maintain its blood glucose concentration? What happens when blood glucose concentration rises to her or falls too low?

Hormones are secreted in response to fluctuations in blood glucose. When blood glucose is too high, the pancreas releases insulin, resulting in the storage of glucose in the cells; when blood glucose is too low, the pancreas releases glucagon, resulting in the release of glucose into the blood.

10. What are the possible fates of glucose in the body? what is the proteins sparing action of carbohydrate?

It can be stored as glycogen; it can be used for energy; it can be converted to fat, when carbohydrate is available; it can be used for energy, leaving protein available for its special functions.

3. Describe the structure or polysaccharides and name the ones important in nutrition. How are starts and glycogen similar, and how do they differ? How do the fiber is different from the other polysaccharides

Polysaccharides are composed of many monosaccharides strung together. Important in nutrition are: glycogen, starch and the fibers. Starch and glycogen are similar in that they are both composed of glucose; they differ in the way their glucose units are linked together (glycogen consists of many glucose molecules linked together in highly branched chains, while starch consists of many glucose molecules linked side by side). Fibers are different in that the bonds between their monosaccharides cannot be broken.

3. Describe the structure or polysaccharides and name the ones important in nutrition. How are starts and glycogen similar, and how do they differ? How do the fiber is different from the other polysaccharides?

Polysaccharides are composed of many monosaccharides strung together. Important in nutrition are: glycogen, starch and the fibers. Starch and glycogen are similar in that they are both composed of glucose; they differ in the way their glucose units are linked together (glycogen consists of many glucose molecules linked together in highly branched chains, while starch consists of many glucose molecules linked side by side). Fibers are different in that the bonds between their monosaccharides cannot be broken.

17. What are the health effects of starches and fiber's? What are the dietary recommendations regarding these complex carbohydrates

Protect against heart disease, colon cancer, and diabetes, assist in weight control, improve large intestine function and health, lower blood cholesterol levels, and slow the rate of glucose absorption. 55 to 60% of total kcalories should come from carbohydrate; mostly from starch, some from fruits, vegetables, and milk.

17. What are the health effects of starches and fiber's? What are the dietary recommendations regarding these complex carbohydrates?

Protect against heart disease, colon cancer, and diabetes, assist in weight control, improve large intestine function and health, lower blood cholesterol levels, and slow the rate of glucose absorption. 55 to 60% of total kcalories should come from carbohydrate; mostly from starch, some from fruits, vegetables, and milk.

16. Describe the risk and benefits of using alternative sweeteners

Risks: Weight gain/ obesity epidemic. Benefits: reduce incidence of dental caries Manages blood sugar levels in diabetes

16. Describe the risk and benefits of using alternative sweeteners

Risks: Weight gain: obesity epidemic.

7. describe carbohydrate digestion and absorption. What role does fiber play in the process?

Salivary amylase enzymes in the mouth partially break down some of the starch before it reaches the intestine, pancreatic enzymes digest the starch to disaccharides in small intestine, disaccharidase enzymes on surface of intestinal wall cells split disaccharides to monosaccharides, monosaccharides enter capillary, capillary delivers monosaccharides to liver, liver converts galactose and fructose to glucose. In the mouth, fiber slows the process of eating and stimulates the flow of saliva; in the stomach, they delay gastric emptying; in the small intestine, they delay absorption of carbohydrates and fats, and can bind with minerals; in the large intestine, they attract water that softens the stools.

14. What does the pancreas secrete with blood glucose rises? When blood glucose falls?

a) Insulin; glucagons

8. The ultimate goal of carbohydrate digestion and absorption is to yield

b) Glucose

5. The making of a disaccharide from two monosaccharides is it example of

c) Condensation

4. disaccharides include:

c) Sucrose, maltose, and lactose

6. The significant difference between starch and cellulose is that

d) Digestive enzymes can break the bonds in starch, but not in cellulose

12. The storage form of glucose in the body is

d) Glycogen

9. The enzyme that breaks a disaccharide it's a glucose and galactose is

d) Lactase

13. With insufficient glucose in metabolism, fat fragments combined to form

ketone bodies

19. carbohydrate I found a virtually all foods except

meat