Download Proteins - Mr. McKittrick`s Website


Make up ~10% of daily calories

Are not a primary energy source
› Carbohydrates and fats are!

Important in maintaining and replacing body
tissues (growth)

Found in almost every living cell and liquid
› Blood (clotting)
› Muscles, organs
› Used to make hemoglobin

Enzymes are proteins!

Accelerate the rate of metabolic
reactions
› Ex. food digestion

Highly selective catalysts
› Increase the rate of reaction, not a reactant

Amino acids (aa’s) are the building blocks
of proteins (monomers)

20 different amino acids make up >20,000
proteins in the body
Amine
group
Carboxylic
acid
Functional group
Amino Acid 1
Amino Acid 2

Chains of amino acids

Multiple polypeptides join together to
form a functional protein
Meat: Beef, poultry, pork and lamb
 Fish and shellfish
 Dairy products: cottage cheese, cheese,
yogurt, and milk
 Egg whites, and egg substitutes
 Dry beans, peas, oats and legumes
 Tofu and soy products
 Nuts and seeds


Our bodies can synthesize 12
out of 20 of the amino acids

We need to get the other 8
amino acids from our food
› They are called essential amino
acids
Complete Proteins
Incomplete Proteins
Contain all 8 essential
amino acids
Do NOT contain all 8
essential amino acids
(“partial proteins”)
“Animal” proteins
“Plant” proteins
Fish, meat, poultry,
eggs, yogurt, milk,
cheese
Legumes, grains, nuts,
seeds, beans, corn
**Incomplete proteins must be
combined
to obtain all 8 essential aa’s:

**Incomplete proteins must be combined
to obtain all 8 essential aa’s:
EXAMPLES:
Grains and Legumes
 peanut butter + whole wheat bread
 rice + beans
 bean soup + roll
 tofu vegetable stir-fry + rice/pasta
Grains + Nuts
 whole wheat bun + sesame seeds
 rice cakes + peanut butter
 breadsticks rolled in sesame seeds
Legumes + Nuts
 hummus (chickpeas + sesame paste)
 trail mix (peanuts + sunflower seeds)
**Add small amounts of animal protein to
any group to get a complete protein
e.g. yogurt + granola
macaroni + cheese
oatmeal + milk
bean + cheese burrito
salad with beans + hard boiled egg
1) Kwashiorkor
 causes fluid retention
(edema), dry skin, hair
discoloration
 liver enlargement and fluid
retention can distend the
abdomen and disguise
weight loss
 anemia, diarrhea, and fluid
and electrolyte disorders are
common

High cholesterol can lead to
atherosclerosis, coronary artery disease
and strokes

On its own, cholesterol is healthy around
the body:
› Found in cell membranes
› Crucial for growth in babies

Cholesterol is a lipid, it can't dissolve in
water or blood
› It needs “help” to get through the body

Cholesterol combines with protein,
forming a lipoprotein (lipid + protein)
› The protein coats the cholesterol
› 2 types: high density (HDL) and low density
(LDL)
More protein than cholesterol
 Drives like a FERRARI, speeding straight to
the liver, then gets converted into bile
acids
 “Good" cholesterol

› Protects against heart attack
› Removes excess cholesterol from arterial
plaque, slowing its buildup
More cholesterol than protein
 Drives like an old beater, runs into arterial
walls, adds to platelets and plaque
 “Bad” cholesterol

› Plaques can lead to heart attacks etc.
Type of fat made in the body
 Elevated triglycerides can be due to:

› obesity, inactivity, smoking, excess alcohol
consumption and >60% dietary
carbohydrates

High triglycerides often accompanies
high total cholesterol level
› high LDL (bad) level and a low HDL (good)
level
Genetic variation of LDL (bad)
cholesterol
 High level is a risk factor for fatty deposits
in arteries

› May interact with substances found in artery
walls and contribute to the buildup of fatty
deposits