Protein

Question 1

Types of protein

Answer 1

Collagen: structural - cartilage, ligaments, bones
Contractile: enables muscles to move
Structural: hair, skin, nails - keratin
Clotting: blood clotting

Also: nearly all enzymes, hormones (insulin and glucagon), transport proteins (albumin)

Question 2

Amino acids

Answer 2

Essential: cannot be made by the body, must be supplied by diet (9/20)

Non-essential: can be made by the body (11/20)

Question 3

Protein quality

Answer 3

High quality/complete: contains all 9 essential amino acids (animal products, quinoa, processed soy)

Low quality/incomplete: lacks/has inadequate amounts of 1+ essential amino acids (most plant foods)

Question 4

Denaturation

Answer 4

Heat: cooking raw eggs
Acid: hydrochloric acid denatures food proteins in stomach for digestion
Alcohol
Physical agitation (beating an egg)

Question 5

Recycling

Answer 5

Proteins can be recycled in an amino acid pool
Endogenous AA: available from pool
Exogenous AA: not available from pool

Question 6

Complementary proteins

Answer 6

Mixing certain plant foods to get all AA without adding animal proteins

• red beans and rice
• PB bagel with wheat germ

Question 7

Protein deficiency

Answer 7

Elderly, poor, alcoholics, people with anorexia

Kwashiorkor: adequate energy intake but low intake of high quality protein –> edema
Marasmus: not enough calories or protein –> extreme weight loss