proteins

Question 1

what are proteins

Answer 1

They are the predominant structural and functional material in every cell. They are polypeptides made of amino acids and joined by peptide bonds.

Question 2

why are proteins important

Answer 2

• they are the structural and functional basis of every cell
• breaks down into amino acids for many uses

Question 3

what are the components making up proteins

Answer 3

Contain: carbon, hydrogen, oxygen (like carbs and fats)
Made up of 20 unique amino acids: central carbon atom with amino group, side chain (gives specific characteristics to protein), hydrogen, carboxy group
They are polypeptides made of amino acids and joined by peptide bonds.
Dipeptide bond: acid and amine group connect

Question 4

how does the body digest proteins

Answer 4

• HCl denatures proteins and activates pepsin which breaks down proteins into smaller polypeptides
• In small intestine: proteases cleave peptide bonds so polypeptides are broken down into tri/dipeptides and amino acids
• Accessory organs: Pancreas produces proteases and liver uses AA to make new proteins or converts them to glucose

Question 5

how does the body absorb proteins

Answer 5

Amino acids absorbed into blood stream and travel through portal vein to liver

Question 6

functions of proteins

Answer 6

• Amino acids can be made into body proteins or non protein substances
• After amine group removed from AA they can be burned for energy, stored as fat, made into glucose
• Provide structural and mechanical support in tissues with collagen and connective tissues
• Enzymes and hormones are made of proteins
• Regulate fluid balance
• Maintain acid/base balance with buffers (plasma proteins)
• Transport substances through out body with transport proteins
• Contribute to healthy immune system with proteins called antibodies
• Provide energy
• Improves satiety and appetite control

Question 7

what are the daily protein needs

Answer 7

AMDR: 10-35% of total daily cal
RDA: is 0.8 grams of protein per kilogram of body weight, or 0.36 grams per pound
RDA adult women: 46g/day
RDA adult men: 56g/day

Question 8

Identify healthy sources of protein

Answer 8

• Soy products like tofu and edamame
• Quinoa and lentils
• meat alternatives like beans, nuts, peanut butter, soy
• meat, poultry, fish

Question 9

Explain health consequences of consuming to much protein

Answer 9

• Increase risk of: heart disease, kidney stones, calcium loss from bones,
• Can displace other nutrients and fiber rich foods

Question 10

Explain health consequences of consuming to little protein

Answer 10

• Reduced lean body mass
• Risk of: increased frailty, impaired healing, decreased immune function
• Protein energy malnutrition(PEM): inadequate cal/protein
• Kwashiorkor: severe protein deficiency
  Signs: swollen abdomen, moon face, edema, muscle loss, skin rash, water/electrolyte imbalance
• Marasmus: severe calorie deficiency
  Signs: emaciation, lack of growth, loss of fat

Question 11

benefits and risks of vegetarian diet

Answer 11

Benefits: reduce risk of heart disease, high BP, diabetes, cancer, stroke, obesity.
Diet is rich in fiber and low in saturated fats and cholesterol.
Risks: potential deficiencies of nutrients found in animal foods like protein, iron, zinc, calcium, Vit D, riboflavin, B12, A, omega 3 fatty acids

Question 12

essential AA
nonessential AA
conditionally essential AA

Answer 12

essential: 9, cant be made by body
nonessential: 11, can be made by body with essential AA
conditionally essential: some times with trauma or pregnancy need more