Nutrition-Chapter 6 Proteins PDF

Preview

Summary

Notes taken from PowerPoint by Professor DIMarco...

Description

Nutrition-Chapter 6: Proteins What’s a Protein? Macronutrient Kcal Organic Smallest unit- Amino Acid Only one that contains nitrogen 20 side chains Amino Acids 20 amino acids ➔ 9 essentials ➔ 11 nonessentials Conditionally essential amino acids ➔ Could have a condition that does not make amino acids Amino acids connect to form peptides Peptide: chain of amino acids (a protein) How do we digest proteins? Mouth ➔ No enzymes Stomach ➔ Acid causes denaturation ➔ Proteins are tangled up and need to be unfold ➔ Pepsin (enzyme) Proteins are the most difficult for the body to digest Small Intestine ➔ Proteases from the pancreas Protein Turnover Amino acids are absorbed into the amino acid pool ➔ Body is recycling amino acids from food for different uses, to be used at different times How does the body know how to build each protein? DNA is the code DNA is the template and we unfold the section that we need that we need and make a copy = RDNA copy

Protein Structure Primary structure ➔ Sequence of amino acids Secondary Structure ➔ Local (small) structure ➔ Determined by side chains ➔ Positive and negative charges will attract and fold together Tertiary Structure (3rd level) ➔ Overall structure ➔ Determined by side chains Quaternary Structure (4th level) ➔ Joining of multiple peptide chains

Structure determines function Loss of structure = loss of function What would cause this? ➔ Denaturation: unfold and loss of purpose

➔ ➔ ➔ ➔ ➔

Heat PH level Chemical DNA error: instructions can have a problem causing a problem throughout Protein building error: Adding wrong amino acid

DNA Errors are the cause of some diseases Sickle Cell Anemia ➔ Hemoglobin (oxygen travels through blood) gets built incorrectly and cannot carry oxygen through. Red blood cells are not fluffy, plump and do not work properly. What does the body use protein for? Structure: growth, maintenance and repair Enzymes: Function and all proteins helps every process in your body to stay alive Some Hormones Immune System: antibodies Proteins Fluid Balance: keeping the right amount of water in your body. Proteins in blood help control water levels Proteins help transport items throughout the body Energy from Proteins ➔ Last resort ➔ Have to remove nitrogen ➔ Forms ammonia (toxic for the body) ➔ Urea (convert ammonia to urine, then pee it out) How much protein do we need? RDA: 0.8g/kg/day AMDR: 10-35% kcal Adequate calories from carbs and fats What happens if we eat too much protein? Animal proteins provide saturated fat ➔ Heart Diseases Problematic for people with kidney disease Too Little Protein Kwashiorkor (“First Child Syndrome”) ➔ Usually seen in the first child after they stop getting breast fed ➔ Weight/Muscle loss ➔ Ascites ➔ Slow Growth

➔ Skin, hair, and organ damage ➔ Weak immune system Marasmus (“dying away”) ➔ Extreme wasting ➔ Severe stunting (vertical growth) ➔ Severe organ damage MyPlate for Vegetarians Plant Based Proteins ➔ Legumes ➔ Soy ➔ Nuts ➔ Seeds ➔ Whole grains...