1. The Digestive System Food and Energy
Chapter 15-section 1

2. Key Concepts Why does your body need food?
How do the six nutrients needed by the body help carry out essential processes?
How can the Food Guide Pyramid and food labels help you have a healthy diet?

3. Key Terms Nutrient Calorie Carbohydrate Glucose Fat Protein Amino acid
Vitamin
Mineral
Food guide pyramid
Percent daily value
Dietary reference intakes (DRI’s)

4. Why you need food
Food provides your body with materials for growing and for repairing tissue
Food also provides energy for everything you do
Ex-running, reading, sleeping,
Food also helps your body maintain homeostasis

5. Nutrients Your body breaks down the foods you eat into nutrients
There are six groups of nutrients necessary for human health
Carbohydrates, fats, proteins, vitamins, minerals, and water

6. Energy
When nutrients are used by the body for energy, the amount of energy they release can be measured in units called calories
Calorie with a C is used to measure the energy in foods
You need to eat a certain number of calories each day to meet your body’s energy needs
Your daily energy requirement depends on your level of physical activity, the more active you are the greater your energy needs are

7. Carbohydrates
They are composed of carbon, oxygen, and hydrogen and are a major source of energy
One gram of carbohydrate provides your body with four Calories of energy
Carbohydrates provide the raw materials to make cell parts. They are divided into simple carbohydrates and complex carbohydrates

8. Simple carbohydrates
These carbohydrates are known as sugar and provide quick energy for the body

9. Complex Carbohydrates
Complex carbohydrates are made up of many sugar molecules lined together in a chain
Starch is a complex carbohydrate found in foods from plants such as potatoes, rice, wheat, corn
Fiber is a complex carbohydrate but unlike starch fiber cannot be broken down into sugar molecules, instead fiber passes through the body and is eliminated
Fiber helps keep the digestive system functioning properly

10. Fats
Fats contain more than twice the energy of an equal amount of carbohydrates
Fats form part of the cell membrane, the structure that forms the boundary of a cell
Fatty tissue protects and supports your internal organs and insulates your body

11. Kinds of fats saturated and unsaturated
Unsaturated fats are usually liquid at room temperature-olive oil
Saturated fats are usually solid at room temperature-Crisco
Trans fats help keep food fresher longer and are considered to be less healthful than unsaturated fats

12. Cholesterol Waxy, fatlike substance found only in animal products
Your liver can make all of the cholesterol your body needs and is not a necessary part of the diet

13. Proteins Are needed for tissue growth and repair
They also play an important part in chemical reactions within cells
10-35 percent of your daily Calorie intake should come from proteins

14. Amino Acids
Proteins are made up of small units called amino acids which are linked together chemically to form large protein molecules

15. Complete and Incomplete Proteins
Complete proteins-meat and eggs, these foods contain all the essential amino acids
Incomplete proteins-come from plant sources such as beans, grains and nuts. They are incomplete because they are missing one or more essential amino acid

16. Vitamins and Minerals
Unlike other nutrients V & M do not provide the body with energy or raw materials
Instead they help the body carry out various processes
Vitamins act as helper molecules in a variety of chemical reactions-
Ex – Vitamin K helps blood to clot
Vitamin D can be made when your skin is exposed to sunlight

17. Fat Soluble and Water Soluble Vitamins
Fat soluble vitamins dissolve in fat and they are stored in fatty tissues in the body
Vitamins A, D, E, and K are all fat soluble vitamins
Water-soluble vitamins dissolve in water and are not stored in the body
Vitamins- C and D are water soluble vitamins

18. Importance of Vitamins
Vitamins are only needed in small amounts
A lack of certain vitamins in the diet can lead to health problems

19. Importance of Minerals
Minerals are present in soil and are absorbed by plants through their roots
Minerals are obtained by eating plant foods or animals that have eaten plants
Ex. Calcium-strong bones and teeth
Iron is needed for the proper functioning of red blood cells

20. Vitamins and Minerals
Are needed by your body in small amounts to carry out chemical processes

21. Water Water is the most abundant substance in the body
It accounts for 65 percent of the average person’s body weight
People cannot survive without fresh water

22. Where do the body’s vital processes take place?
Water
The body’s vital processes including chemical reactions such as the break down of nutrients take place in water
Cells in your body are mostly composed of water

23. (2)
Nutrients and other important substances are carried throughout the body dissolved in the watery part of the blood
Water in blood also carries waste materials that must be removed from your body
Perspiration consists of chemicals dissolved in water,comes from body tissue, and helps regulate body temperature by cooling the body

24. The Food Guide Pyramid

26. Food Guide Pyramid Classifies foods into six groups
Indicates how many servings from each group should be eaten everyday to maintain a healthy diet

27. 1. What are some reasons that your body needs food?
Feel your best, perform well in school and sports, reduce your risk of illness

28. 2. How are fats beneficial
They provide energy form part of cell membranes, protect and support internal organs, insulate your body

29. 3. Are vitamins and minerals sources of energyno

30. 4. Why is it important to get vitamins and minerals from food?
The body cannot make minerals and some vitamins

31. 5. To obtain enough calcium what foods should people eat if they do not drink milk?
Cheese, dark green leafy vegetables

32. 6. What does the body use calcium for?
Building bones and teeth, clotting blood and nerve and muscle function

33. 7. How does water work with vitamins and minerals to carry out body processes?
Vitamins and minerals help carry out chemical reactions which take place in water

34. 8. Why are the food groups shaped like a pyramid
The wider base indicates that the greatest portion of persons diet should be from this group

35. 9. Name two ways in which foods are used by the body?
Growing, repairing tissues, providing energy, maintaining homeostasis

36. 10. What is a calorie?
The amount of energy needed to raise the temperature of one gram of water by one degree Celsius, the more Calories a food has the more energy it contains