| A | B |
|---|
| proteins | contain carbon, hydrogen, oxygen, and nitrogen; 16% nitrogen |
| amino acids | building blocks of protein |
| amino | containing nitrogen |
| essential amino acids | 9 amino acids that the body cannot synthesize |
| nonessential amino acids | 11 amino acids that the body synthesizes |
| amino acid configuration | hydrogen, carbon, amino group, and side group |
| peptide bond | links amino acids in a protein chain |
| dipeptide | two amino acids bonded together |
| tripeptide | three amino acids bonded together |
| polypeptide | ten or more amino acids bonded together |
| hemoglobin | quaternary structure (4 polypeptide chains) |
| denaturation | chain in a protein's shape and function |
| pepsin | hydrolyzes proteins into smaller polypeptides |
| pepsinogen | inactive form of pepsin |
| proteases | hydrolyze proteins into small amino acid chains |
| peptidases | split proteins into individual amino acids |
| functional proteins | collagen and keratin |
| structural proteins | enzymes, hormones, and antibodies |
| anabolic | building up |
| catabolic | breaking down |
| edema | fluid retention due to plasma proteins |
| proteins as buffers | keep solutions acidic or alkaline |
| acids | compounds that release hydrogen ions |
| bases | compounds that accept hydrogen ions |
| acidosis | high levels of acidity in the blood |
| antigens | bodily invaders such as viruses and bacteria |
| immunity | ability to fight an antigen |
| protein turnover | the making and breaking-down of protein |
| nitrogen balance (NB) | nitrogen intake (NI) - nitrogen loss (NL) |
| nitrogen intake (NI) | protein intake (in g/day) divided by 6.25 |
| neurotransmitters | made from the amino acid tyrosine |
| tyrosine | can be made into thyroxine |
| tryptophan | makes niacin and serotonin |
| excess protein | deaminated and converted into fat |
| deamination | removal of amino groups |
| products of deamination | ammonia and keto acids |
| transamination | transferring an amino group to a keto group |
| urea | product of ammonia and carbon dioxide |
| kidneys | filter urea out of the blood |
| high-protein diets | require increased water intakes |
| animal proteins | 90% - 99% absorbed |
| plant proteins | 70% - 90% absorbed |
| soy and legumes | 90% absorbed |
| limiting amino acids | deficiency of essential amino acids |
| high-quality proteins | contain all the essential amino acids |
| complementary amino acids | plant food blend containing essential amino acids |
| DRV for protein | 50g based on a 2000 kcal diet |
| children with chronic protein malnutrition | are small (short) for their age |
| animal proteins | tend to be high in saturated fat |
| high-protein intakes | associated with increased calcium excretions |
| recommended protein intakes | 10% - 35% of energy intake |
| protein RDA | .8 g/kg for most adults; 1.2 -1.7 g/kg for athletes |
| protein powders | no proof of improved performance |
| whey protein | waste product of cheese manufacturing |
| ribosome | cell structure where protein synthesis occurs |
| RDA protein-to-calcium ratio | > 20-to-1 (milligrams to grams) |
| protein-based hormones | all hormones except for sex hormones and corticoid hormones |
| 1 gram of protein | yields 4 kcal of energy |
| legumes | provide isoleucine and lycine |
| grains | provide methionine and tryptophan |
