1. Topic: The Digestive System
Aim: What are nutrients?
Do Now: Why do we eat food? How does every cell in the body get nutrients?

2. Food and Nutrition What are nutrients?
Nutrients: substances in food that provide the body with the energy the body needs to carry out all essential processes.
Calorie: used to measure the amount of energy in food
(more calories = more energy)

3. What are the 6 Nutrients?
1. Carbohydrates: the body’s main source of energy
a) simple carbohydrates = sugars (quick energy)
Examples:
Candy bar, donuts
b) complex carbohydrates = starch and fiber
Examples:
Bread, cereal, grains
*Fiber cannot be broken down by our bodies!

4. Topic: The Digestive System
Aim: How do vitamins & minerals help the body?
Do Now: What is a calorie? How is extra energy stored in the body?

5. 2. Fats: high energy nutrients
Unsaturated Fats: liquid at room
temperature (oil)
b. Saturated Fats: Solid at room
temperature (animal products)
*High in saturated fat usually =
high in cholesterol

6. 3. Proteins: needed for tissue growth
and repair (Made up of amino acids)
Examples:
Turkey
Beef
Pork

7. 4. Vitamins: Act as helper molecules in
chemical reactions within the body
Examples:
Vitamin A – Maintains healthy skin,
bones, teeth, and hair; aids vision in dim light
Found in: Dairy products; eggs; liver;
yellow, orange and dark green vegetables;
fruits

8. Vitamin D – Maintains bones and teeth; helps in the use of calcium and
phosphorus
Found in: dairy products; fish; eggs; live; made by skin cells in the presence of sunlight
Vitamin E – Aids in maintenance of red
blood cells
Found in: Vegetable oils; green, leafy
vegetables; whole grains, seeds and nuts

9. Vitamin K – Aids in blood clotting
Found in: Green, leafy vegetables;
milk, liver; made by bacteria in the intestines

10. Examples: 5. Minerals: Found naturally on earth;
obtained by eating plants
Examples:
Calcium- helps build bones and teeth;
important for blood clotting, nerve and muscle function (milk, cheese, tofu)
Iron- forms an important part of red
blood cells (meats, vegetables & fruit)

11. Topic: The Digestive System
Aim: What is the digestive process?
Do Now: Give the name and food source of three types of nutrients.

12. Potassium- helps maintain water balance;
needed for normal muscle and nerve
Function (grains; fruits; vegetables; meat; fish)
Sodium – Helps maintain water
balance; needed for normal nerve function
(table salt; soy sauce; processed foods)

14. Water 60% of the body is water (most found within our cells)
Cells need water to carry out life processes
Nutrients from food need to dissolve in water in order to get throughout the body
Most chemical reactions in the body take place in solutions

15. The Digestive Process Digestion is a 3 step process:
Food is broken down into smaller
molecules.
2) Molecules are absorbed into the blood and carried throughout the body.
3) Wastes are eliminated from the body

17. Absorption: passage of nutrients from the
digestive system into your blood
Ingestion
Digestion
Absorption
Egestion
Saliva plays an important role in the 2 types of digestion (both begin in the mouth)…

18. Topic: The Digestive System
Aim: What is the digestive system?
Do Now: What two types of digestion take place in the mouth? How are they similar and different?

19. 2 Types of Digestion Saliva + Starch = Sugar
Mechanical Digestion: breaks down large
food molecules into smaller ones using your
teeth to chew your food and mixing it with your tongue.
2. Chemical Digestion: begins with the addition of a watery substance called saliva
that breaks food molecules down into different substances…
Saliva + Starch = Sugar

20. Organs of the Digestive System
Your digestive system has 2 parts—the digestive tract and the accessory organs.
The 7 major organs of your digestive tract are:
1. mouth large intestine
2. esophagus 6. rectum
3. stomach 7. anus
4.small intestine

21. The accessory organs are the: tongue, teeth, salivary glands, liver, gallbladder, and pancreas.
They are important in mechanical and
chemical digestion.
Your liver, gallbladder, and pancreas produce or store enzymes and chemicals that help break down food.

22. Enzymes: proteins that speed up chemical reactions in the body
*Specific Shape = Specific Reaction
Digestive Enzymes
Mouth: salivary amylase
Stomach: pepsin, hydrochloric acid
Pancreas: amylase, trypsin, lipase

23. Topic: The Digestive System
Aim: What is the digestive system?
Do Now: What are the 7 major organs of the digestive system? What is an enzyme? How do enzymes help digestion?

24. The Mouth

25. Food mixed with saliva becomes a soft mass and is moved to the back of your mouth by your tongue.
It is swallowed and passes into your esophagus.
Food moving into the esophagus passes over the epiglottis

26. Epiglottis: flap of tissue that seals off your
windpipe
Esophagus: muscular tube that connects
the mouth and the stomach
Mucus: thick, slippery substance that makes food easier to swallow

27. Topic: The Digestive System
Aim: What is the role of the intestines?
Do Now: How does the body prevent food from entering the windpipe (trachea) when swallowing?

28. Peristalsis: muscle contractions that push
food through the digestive system
Stomach: j-shaped organ
most mechanical digestion takes
place here
chemical digestion
digestive juices contain pepsin, hydrochloric
acid, & mucus

30. Small intestine: most of the chemical digestion takes place
*Almost all chemical digestion and absorption
of nutrients takes place in the small intestine!
Contains villi – tiny hair-like structures – that increase surface area for absorption.
From here, blood transports the nutrients to all cells of your body.

31. Topic: The Digestive System
Aim: How does the digestive system prevent dehydration?
Do Now: What is peristalsis? What happens when peristalsis is reversed in the esophagus?

32. Peristalsis continues to force the remaining undigested and unabsorbed materials slowly into the large intestine.
The main job of the large intestine is to absorb water from the undigested
mass.

33. After the excess water is absorbed, the remaining undigested materials become more solid.
Muscles in the rectum, which is the last section of the large intestine, and the
anus control the release of semisolid wastes from the body in the form of
feces (FEE seez).

34. Gallbladder: organ that stores bile
Liver: produces bile – a substance that breaks up fat particles, medicine and other substances.
Gallbladder: organ that stores bile
Pancreas: Produces enzymes that break down starches, proteins and fats
LIVER
GALL BLADDER
PANCREAS

35. Topic: The Digestive System
Aim: How does food travel through the digestive system?
Do Now: What is the function of the large intestine?

36. QUESTION:
The foods in this illustration are rich in _______.
A. carbohydrates
B. fat
C. minerals
D. protein
The answer is D. Your body uses proteins for replacement and repair of body cells.

37. QUESTION:
This illustration represents _______.
A. absorption
B. digestion
C. elimination
D. ingestion
The answer is D. Ingestion occurs as food enters your mouth.

38. QUESTION:
_______ are a type of protein that speeds up the rate of a chemical reaction in your body.
The answer is enzymes. Enzymes reduce the amount of energy necessary for a chemical reaction to begin.

39. QUESTION:
Which is a major organ in your digestive tract?
A. esophagus
B. gallbladder
C. pancreas
D. salivary glands
The answer is A. The major organs of the digestive tract are mouth, esophagus, stomach, small intestine, large intestine, rectum, and anus. Food passes through all of these organs.

40. QUESTION:
Which is a function of the large intestine?
A. Absorbs water from undigested mass
Produces bile and breaks up large fat
particles
C. Produces hydrochloric acid and chyme
D. Takes food to the stomach
The answer is A. The large intestine keeps large amounts of water in your body and helps maintain homeostasis.

41. QUESTION:
Which begins the process of chemical digestion?
A. esophagus
B. saliva
C. teeth
D. tongue
The answer is B. Chemical digestion begins with the addition of a watery substance called saliva. Saliva is produced by three sets of glands near your mouth.

42. Topic: The Digestive System
Aim: Excellent test scores!!!!
Do Now: Review your notes for 5 minutes.
HW: Lab conclusion questions due Monday.