Transcript NUTRITION/DIGESTIVE SYSTEM

NUTRITION/DIGESTIVE
SYSTEM
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 Right
A. Follow the new Food Plate
1. 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