NUTRITION/DIGESTIVESYSTEM

NUTRITION

I. NUTRIENTS – 6 A. Carbohydrates – sugary or starchy food

1. Fruits, vegetables, grains, potatoes, pasta, & fiber (undigestible cellulose)

2. polysaccharide (many sugars)

monosaccharide (1 sugar)

S – S – S – S – S – S – S – S – S – S – S

3. used for energy for cell respiration

B. Fats (Lipids)/Oils

1. ex. Butter, ice cream, red meat, cookies, chips, french fries, cheese

2. Fats Fatty Acids

FA - FA - FA

3. Used for energy (burned last, often stored as fat)

C. Protein

1. ex. Meat, fish, nuts, beans, eggs, & dairy products

Protein

Protein

2. Polypeptides amino acids

AA – AA – AA – AA – AA – AA – AA – AA

3. used for body building & repair of muscles, organs, cells, blood, hair, & fingernails

D. Vitamins

1. organic substance found in tiny amounts in plants & animals

2. Vitamin A (carrots: eyes)

Vit. C (citrus fruits: immune system)

Vit. D (sun, milk: bones)

Vit. K (made in l.i.: clots blood)

Vitamins

E. Minerals

1. inorganic substance found in water & foods

2. ex. Sodium (salt: nerves & muscles) Potassium (bananas: nerves & muscles) Calcium (milk: bones) Iron (red meat: blood)

F. Water

1. need 8 glasses/day; most of body contains water

2. needed for chemical reactions, digestion, etc.

Nutrients

II. Living RightA. Follow the new Food Plate1. eat mostly breads & cereals, then

fruits & vegetables, then milk & meat

2. go sparingly on the fats, oils, & sweets

B. Exercise

1. minimum 5x/wk – 30 min.; (kids – 7x/wk – 60 min.)

2. cardiovascular exercises to strengthen heart

3. weights to strengthen bones & prevent osteoporosis

4. stretching to prevent injury

C. Watch your weight – keep within recommended levels

D. Watch your cholesterol – should be under 200 to help prevent heart attacks & strokes

E. Have regular check-ups by your physician

DIGESTIVE SYSTEM

I. Types of Digestion A. Mechanical/Physical – breakdown by

physical means – does not change chemically; ex. chewing, churning, wetting

B. Chemical breakdown chemically into new substance by enzymes; ex. amylase, pepsin, sucrase, lipase

Types of Digestion – 0:27

II. Digestive System Structures

A. Mouth

1. teeth – grind food; ex. molars, bicuspids, cuspids, incisors; brush min. 2x/day; floss; see dentist 2x/year

2. tongue maneuvers food into a bolus

3. salivary glands – produces saliva: water, mucous, & amylase (converts starches to sugars)

(epiglottis – flap which covers windpipe)

Mouth Digestion – 1:08

B. Esophagus – connects mouth to stomach;

peristalsis (involuntary muscle contraction which pushes food down through digestive tract)

C. Stomach – makes gastric juice: mucous, HCl (enables pepsin to work & kills bacteria), and pepsin (begins breaking down protein)

Stomach Digestion – 1:33

D. Small Intestine (most digestion & absorption)

1. secretes intestinal juice – digests proteins, starches, & fats

2. villi – fingerlike projections lining through which nutrients are absorbed

SMALL INTESTINE HELPERS – (undigested food does NOT pass

through the liver or pancreas)- LIVER – produces bile (separates fat);

gall bladder stores bile

- PANCREAS – produces pancreatic juice; helps digest all 3 nutrients

Small Intestine – 2:15

E. Large Intestine (colon)

1. Undigested food (cellulose) forms feces

2. Water & minerals absorbed through walls into blood

3. Vit. K made

4. Mucous helps bind & wastes excreted out

Large Intestine – 0:58

Final Stage of Digestion – 0:21