Term | Definition |
protein(peptide) | nitrogen-containing macronutrient made from amino acids |
amino acid | nutrient composed of a central carbon bonded to an amino group, carboxylic acid group, and a side-chain group(R-group) |
peptide bond | a chemical bond that joins amino acids |
polypeptide | a string of 13+ amino acids held together via peptide bond |
amino group | the nitrogen-containing component of an amino acid |
R-group | the portion of an amino acid's structure that distinguishes it from other amino acids |
alpha-keto acid | a compound that accepts an amino group from an amino acid in the process of transamination |
transamination | the process whereby an amino group is formed via the transfer of an amino group from one amino acid to another organic compound |
phenylketonuria(PKU) | an inherited disease in which the body cannot convert phenylalanine into tyrosine |
complete protein source | a food that contains all the essential amino acids in relative amounts needed by the body |
incomplete protein source | a food that lacks or contains very low amounts of one or more essential amino acids |
limiting amino acid | the essential amino acid in the lowest concentration in an incomplete protein source |
protein complementation | combining incomplete protein sources to provide all of the essential amino acids in relatively adequate amounts |
high-quality protein source | a complete protein source with high amino acid bioavailability |
low-quality protein source | a food that id either an incomplete protein source or one that has low amino acid bioavailability |
genetically modified organism(GMO) | an organism(plant or animal) made by genetic engineering |
cell signalling | the first step in protein synthesis, in which the cell recieves a signal to produce a protein. Note that this term is also used for a variety of other processes (aside from protein synthesis) within the cell |
up-regulation | in the context of protein synthesis, increased expression of a gene |
down-regulation | in the context of protein synthesis, decreased expression of a gene |
transcription | the process whereby mRNA is made using DNA as a template |
chromosomes | a strand of DNA and associated proteins in a cell's nucleus |
gene | a portion of a chromosome that codes for the primary structure of a protein |
messenger ribonucleic acid(mRNA) | a form of RNA involved in gene transcription |
translation | the process whereby amino acids are linked together via peptide bonds on ribosomes, using mRNA and tRNA |
ribosome | an organelle, associated with the endoplasmic reticulum in the cytoplasm, involved in gene translation |
transfer ribonucleic acid(tRNA) | a form of RNA in the cytoplasm involved in gene translation |
primary structure | the sequence of amino acids that make up a single peptide chain |
sickle cell anemia | a disease in which a small change in the amino acid sequence of hemoglobin causes red blood cells to become misshapen and decreases the ability of the blood to carry oxygen and carbon dioxide |
secondary structure | folding of a protein because of weak bonds that form between elements of the amino acids backbone(not R-groups) |
alpha-helix | a common configuration that makes up many proteins' secondary structures |
Beta-folded sheet | a common configuration that makes up many proteins' secondary structures |
tertiary structure | folding of a polypeptide chain because of interactions among the R-group of the amino acids |
gene therapy | the use of altered genes to enhance health |
quaternary structure | the combining of peptide chains with other peptide chains in a protein |
prosthetic group | a nonprotein component of a protein that is part of the quaternary structure |
denaturation | the alteration of a protein's 3-D structure by heat, acid, chemicals, enzymes, or agitation |
genetic makeup | the particular DNA contained in a person's cells |
mutation | the alteration of a gene |
polymorphism | an alteration in a gene that is present in at least 1% of the population |
epigenetics | alterations in gene expression that do not involve changes in the DNA sequence |
nutrigenomics | the science of how genetics and nutrition together influence health |
gastrin | a hormone, secreted by endocrine cells in the stomach, which stimulates the production and release of gastric juice |
pepsinogen | the inactive from(proenzyme) of pepsin, produced in the stomach |
proenzyme | an inactive precursor of an enzyme |
pepsin | an enzyme needed for protein digestion |
protease | an enzyme the cleaves peptide bonds |
trypsinogen, chymotrysinogen, proelastase, and procarboxypeptidase | inactive proenzymes produced in the pancreas and released into the small intestine in response to CCK |
trypsin, chymotrypsin, elastase, and carboxypeptidase | active enzymes(proteases) involved in protein digestion in the small intestin |
food allergy | a condition in which the body's immune system reacts against a protein in food |
food intolerance | a condition in which the body reacts negatively to a food or food component but does not mount an immune response |
anaphylaxis | a severe and potentially threatening allergic reaction |
catalyst | a substance that increases the rate by which a chemical reaction occurs, without being consumed in the process |
antibody | a protein, produced by the immune system, that helps fight infection |
albumin | a protein important in regulating fluid balance between intravascular and interstitial spaces |
edema | the buildup of fluid in the interstitial spaces |
glucogenic amino acid | an amino acid that can be converted to glucose via gluconeogenesis |
gluconeogenesis | synthesis of glucose from noncarbohydrate sources |
deamination | the removal of an amino group from an amino acid |
protein turnover | the cycle involving both protein synthesis and protein degradation in the body |
labile amino acid pool | amino acids that are immediately available to cells for protein synthesis and other purposes |
urea | a relatively nontoxic, nitrogen-containing compound that is produced from ammonia |
nitrogen balance | the condition in which protein(nitrogen) intake equals protein(nitrogen) loss by the body |
negative nitrogen balance | the condition in which protein(nitrogen) intake is less than protein(nitrogen) loss by the body |
positive nitrogen balance | the condition in which protein(nitrogen) intake is greater than protein(nitrogen) loss by the body |
vegetarian | someone who does not consume any or selected foods and beverages made from animal products |
lacto-ovo-vegetarian | a type of vegetarian who consumes dairy products and eggs in an otherwise plant-based diet |
lactovegetarian | a type of vegetarian who consumes dairy products(but not eggs) in an otherwise plant-based diet |
vegan | a type of vegetarian who consumes no animal products |
protein-energy malnutrition(PEM) | protein deficiency accompanied by inadequate intake of protein and often of other essential nutrients as well |
marasmus | a form of PEM characterized by extreme wasting of muscle and adipose tissue |
kwashiorkor | a form of OEM often characterized by edema in the extremities |
ascites | abnormal accumulation of fluid in the abdominal cavity |