Transcript NUTRITION & DIGESTION - Fox Valley Lutheran High School

NUTRITION & DIGESTION
• Why Food is important
• Calorie: amount of energy to raise the temp. of 1g of water 1
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degree Celsius usually provided by food
1 Calorie = 1000 calories for nutritionists
Adults need roughly 1500 Calories/day depending on how active
you are, kind of work you do, & your gender.
Food supplies energy and building materials
WATER (most important)
– Water is a solvent, coolant, moistener, thinner
– Water is constantly being used and lost within your bodies.
– Replaced by drinking, eating certain foods, & in cellular respiration
FOOD & NUTRITION
• MINERALS (fig. 39-4)
– Inorganic substances required by the body.
– Lost in sweat, urine, and waste products, so they must be replaced.
– Plants get the minerals from the ground, animals eat the plants, and
we eat the plants and animals.
– Replacement of Na, K, and Cl through dairy, salt, meat, & veggies
• CARBOHYDRATES: organic compounds
– Bodies fuel composed of carbon, hydrogen, & oxygen
– Simple sugars, glucose, frutcose, & galactose, are good sources of
quick energy.
– Disaccharides: Maltose, sucrose, lactose, two simple sugars linked
together, enzymes must break the bonds to release the energy.
CARBOHYDRATES
• Polysaccharides: Complex carbohydrates made of stored sugars
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consisting of long chains of monosaccharides. (starch & cellulose)
Starch: bread, corn, rice, potatoes
Must be broken down first through cellular respiration.
Cooked veggies easier to digest the starch.
Cellulose: Part of the cell wall of plants.
Indigestible for humans, but important because it gives us
roughage, which stimulates digestion. Lettuce, celery, whole grain
FATS
Provide protection, keep skin from drying out, parts of the cell
membrane, insulation from environmental changes
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FATS
• The structure of fats
• Organic composed of oxygen, hydrogen, & carbon
• Saturated: single bonds w/maximum H atoms
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Solid at room temp.: butter, lard, animal fat
• Unsaturated: One or more double bonds, so fewer H atoms
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Liquid at room temp.: vegetable oils
• Polyunsaturated: Multiple double bonds, fewest H atoms
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Liquid at room temp.: vegetable oils
• Our diets should be limited in fats, especially saturated fats.
• Fats and Energy
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Provide twice the calories/gram than carbos.
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Stored for late use, deposited under the skin
PROTEINS
• Proteins: complex macromolecules that build & repair for growth
• Essential Amino Acids: The 8 of the roughly 20 your body can’t
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manufacture, must get from your diets.
Meat and dairy contain all 8 amino acids: complete proteins
Most plants lack one or more: incomplete proteins(vegetarians)
Proteins & Energy
Can be used but must be converted into carbos. first
This is done in the liver through deamination in the liver as an
amino group is removed.
Produces ammonia which is converted to urea and removed
from the body by the kidneys.
VITAMINS
• Vitamins are complex molecules needed is small amounts that
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usually cannot be synthesized by the body. (sunlight-Vitamin D)
Vitamins are cofactors for enzyme-catalyzed chemical reactions
Cofactors: Organic catalysts that assist enzymes in reactions
See fig. 39-11 Needed in small amounts
Fat soluble can be stored (A,D,E,K) water soluble can’t (C & B)
Scurvy- bleeding gums, teeth loss, death Need vitamin C
HEALTH AND A BALANCED DIET
Five food groups (see fig. 39-12) Proportions is the key
Fats, oils,& sugars used sparingly
Keep calorie intake balanced no more than 30% from fats