chapter 9 lesson 2 Flashcards
Protein
one of the three macronutrients, serves a variety of important functions in the body. One of the primary functions of protein is in the synthesis and repair of cells, tissues, and structures, such as collagen, elastin, and muscle.
Amino acids
Organic building blocks of proteins containing both a carboxyl and an amino group.
Peptide bond
A chemical bond that connects two amino acids.
Essential amino acid (EAA)
Amino acid that must be obtained through the diet as the body does not make it; there are nine essential amino acids.
Substrates
Intermediate forms of nutrients used in metabolic reactions to create adenosine triphosphate.
Protein turnover
A process in which the body breaks down existing proteins and recycles the component amino acids for incorporation into new proteins or other nitrogen-containing compounds.
Complete protein
A protein source that provides all essential amino acids.
Incomplete protein
A protein that lacks one or more of the amino acids required to build cells.
Omnivorous diet
A diet that consists of both animals and plants.
Mutual supplementation
Combination of two incomplete protein sources that together provide all of the essential amino acids.
Protein quality
Refers to the amino acid profile and the digestibility of a protein source.
Low biological value (LBV) proteins
Foods missing one or more of the essential amino acids.
what makes a protein source quality
its digestibility and its amino acid composition
Protein efficiency ratio (PER):
A value assigned to a protein that is based on the amount of weight gain of a subject divided by the amount ingested of that particular protein during a test period.
high biological value (HBV)
Foods containing all the essential amino acids.
Biological value (BV):
A measure of the digestion and absorption of the amino acids provided by a protein source. BV reflects the amount of the absorbed protein that is used in the synthesis of new proteins in the body.
Protein digestibility–corrected amino acid score (PDCAAS):
Compares the amino acid composition of a food against a standard amino acid profile, with a score of 100 being the highest value possible. It also assesses the food’s digestibility (fecal digestibility) to provide an overall value for the protein’s quality.
Net protein utilization (NPU)
Compares the ratio of amino acids that are turned into proteins to the ratio of amino acids provided via dietary intake
Enterocyte
Intestinal cells that absorb nutrients
Gluconeogenesis
The formation of glucose from noncarbohydrate sources (proteins and fats).
Recommended dietary allowance (RDA)
The recommended amount of a nutrient that meets the needs of most healthy individuals within specific age and gender groups.
Negative energy balance
When calorie intake is lower than the number of calories expended.
