1. What is the difference between a phytochemical and a zoochemical? Provide an example of each.

2. List the macronutrients and micronutrients. Which do we need in larger quantities?

3. Describe the concept of nutrient density. How does it differ from energy density?

4. What is the primary function of the large intestine in digestion?

5. Explain the difference between simple diffusion and active transport in nutrient absorption.

6. Compare and contrast hypoglycemia and hyperglycemia.

7. What is the role of insulin in regulating blood glucose levels?

8. Define complete and incomplete proteins. Give an example of each.

9. What are the potential benefits and risks associated with moderate alcohol consumption?

10. Describe the concept of nitrogen balance and give examples of situations that might lead to positive, negative, and equilibrium nitrogen balance.

Quiz Answer Key

1. Phytochemicals are beneficial compounds found in plants, such as lycopene in tomatoes. Zoochemicals are beneficial compounds found in animal products, such as omega-3 fatty acids in fish.

2. Macronutrients include carbohydrates, proteins, fats, and water. Micronutrients include vitamins and minerals. We need macronutrients in larger quantities than micronutrients.

3. Nutrient density refers to the amount of nutrients a food provides relative to its calorie content. Energy density refers to the number of calories per gram of food. Nutrient-dense foods are rich in nutrients while being relatively low in calories.

4. The large intestine absorbs water and electrolytes and forms and eliminates feces. It also houses a diverse population of gut bacteria that play a role in digestion and overall health.

5. Simple diffusion is a passive process where nutrients move from an area of high concentration to low concentration, requiring no energy. Active transport requires energy to move nutrients against their concentration gradient, from an area of low concentration to high concentration.

6. Hypoglycemia is characterized by low blood sugar levels, while hyperglycemia refers to high blood sugar levels. Both conditions can lead to adverse health effects.

7. Insulin is a hormone produced by the pancreas that lowers blood glucose levels by facilitating glucose uptake into cells for energy use or storage.

8. Complete proteins contain all nine essential amino acids, like those found in meat and eggs. Incomplete proteins lack one or more essential amino acids, like those found in beans and lentils.

9. Moderate alcohol consumption may offer some benefits, like reducing the risk of heart disease. However, excessive alcohol consumption is associated with various health risks, including liver damage and increased cancer risk.

10. Nitrogen balance refers to the difference between nitrogen intake (from protein) and nitrogen excretion. Positive nitrogen balance occurs when intake exceeds excretion, promoting growth and tissue repair. Negative nitrogen balance occurs when excretion exceeds intake, potentially leading to muscle wasting. Equilibrium occurs when intake and excretion are balanced.

Essay Questions

1. Discuss the Dietary Guidelines for Americans, including their purpose, key recommendations, and the diseases they aim to prevent.

2. Explain the different absorptive processes that occur in the small intestine, providing examples of nutrients absorbed through each mechanism.

3. Describe the process of carbohydrate digestion and absorption, including the roles of various enzymes and the fate of glucose after absorption.

4. Compare and contrast the characteristics and functions of different types of lipoproteins, including chylomicrons, VLDL, LDL, and HDL.

5. Discuss the factors that contribute to the development of obesity, including genetic, environmental, and behavioral factors, and outline strategies for preventing and managing obesity.

Glossary of Key Terms

TermDefinitionNutritionThe science of food and its relationship to health.PhytochemicalBeneficial compounds found in plants.ZoochemicalBeneficial compounds found in animals.Functional foodFood that provides health benefits beyond basic nutrition.MacronutrientNutrients needed in large amounts by the body, including carbohydrates, proteins, fats, and water.MicronutrientNutrients needed in small amounts by the body, including vitamins and minerals.Nutrient denseFoods that provide a high amount of nutrients relative to their calorie content.Energy denseFoods that provide a high amount of calories per gram.Essential nutrientNutrient that the body cannot produce on its own and must be obtained from the diet.Nonessential nutrientNutrient that the body can produce on its own, so it is not essential to consume in the diet.DRIDietary Reference Intakes: a set of nutrient intake recommendations for healthy individuals. Includes EAR, RDA, AI, and UL.Daily ValuesNutrient reference values used on food labels to help consumers compare the nutrient content of different foods.DigestionThe process of breaking down food into smaller components that can be absorbed by the body.AbsorptionThe process by which digested nutrients are taken up by the body.PeristalsisCoordinated muscle contractions that propel food through the digestive tract.MonosaccharideThe simplest form of carbohydrate, such as glucose and fructose.DisaccharideTwo monosaccharides linked together, such as sucrose and lactose.PolysaccharideMany monosaccharides linked together, such as starch and fiber.GluconeogenesisThe production of glucose from non-carbohydrate sources, such as amino acids.HypoglycemiaLow blood sugar levels.HyperglycemiaHigh blood sugar levels.Dietary fiberNon-digestible carbohydrates that promote digestive health.Functional fiberNon-digestible carbohydrates that have been added to food to provide health benefits.LipoproteinA complex of lipids and proteins that transport lipids in the blood.Complete proteinA protein that contains all nine essential amino acids.Incomplete proteinA protein that lacks one or more essential amino acids.Complementary proteinsCombining two or more incomplete proteins to provide all nine essential amino acids.DenaturationThe alteration of a protein's structure, often caused by heat or acid.Nitrogen balanceThe difference between nitrogen intake (from protein) and nitrogen excretion.Anaerobic respirationThe process of producing energy without oxygen.Aerobic respirationThe process of producing energy with oxygen.HungerThe physiological need to eat.AppetiteThe psychological desire to eat.SatietyThe feeling of fullness and satisfaction after eating.HypertrophyAn increase in the size of muscle fibers.HypernatremiaHigh blood sodium levels.HyponatremiaLow blood sodium levels.