Chapter 7: Proteins: Amino acids
Peptide Bond
the connection between two amino acids
Undernutrition
the lack of food
Edema
the resulting accumulation of fluid in tissues
Nutrigenomics
the study of how nutrients affect the expression of a person's genome
Your body makes proteins by following information coded in your
DNA
Daily nitrogen losses also occur when
nails and hair grow and the outermost layer of the skin and cells from the intestinal tract are shed
what element is primarily lost through the elimination of urea and creatinine
nitrogen
Lactovegetarian
obtains animal protein by consuming milk and milk products, including yogurt, cheese, and ice cream
Amino acids are the end products of
protein digestion
Primary structure of a protein
refers to the sequence of amino acids liked by peptide bonds
If a person with celiac disease eats food that contains: , the body will activate the immune system, destroying villi
wheat, gliadin, gluten
Nutritional genomics may explain
why dietary interventions can have different effects on the health of different individuals
Polypeptides
Compromised of 50 or more amino acids
A healthy adult's RDA for protein
0.8g/kg of body weight
For healthy adults, the level of consumption is
10-35% of energy from protein
Conditionally essential
Acids that become essential under certain conditions
Essential amino acids
Amino acids that are needed, but cannot be made by the body; they must be eatin in foods
Celiac Disease
An autoimmune disorder that results in poor absorption of nutrients in the small intestine. People with this disease cannot tolerate food with gluten
Nitrogen
An element cells need to make a wide array of important biological compounds such as enzymes and hormones
Low-quality or incomplete protein
Lacks or contains inadequate amounts of one or more of the essential amino acids
What element is part of protein but not part of lipids or carbohydrates?
Nitrogen
Blood urea nitrogen (BUN)
blood test often used to assess kidney function
Amino Acids
building blocks of proteins
Anaphylactic shock
a serious drop in blood pressure that affects the whole body
What elements are combined to make a protein?
carbon, oxygen, hydrogen, nitrogen
To treat children with PEM, children need hospitalization, frequent health assessments, and
carefully controlled refeeding
To make proteins,
cells assemble the 20 amino acids in specific sequences according to the info provided by DNA
Signs and symptoms of celiac disease
chronic diarrhea, abdominal bloating, weight loss
A meal that provides all of the essential amino acids w/out including animal protein consists of
complementary combinations
High quality or complete protein
contains all amino acids in amounts that support protein deposition in muscles and other tissues, as well as supporting the growth of a young child
signs of food intolerance
headache, intestinal discomfort from eating a food w/out triggering the body's immune response
Vegetarians
individuals who rely heavily on plant foods; they may or may not include some animal foods in their diet
Who has an increased RDA for protein?
Children in periods of rapid growth, pregnant women, breastfeeing women
Proteins
Complex molecules that are chemically similar to lipids and carbohydrates b/c they contain carbon, hydrogen, and oxygen atoms
Urinary elimination of urea and creatinine
accounts for most of the lost nitrogen
Protein-energy malnutrition
affects people whose diets lack sufficient protein as well as energy
Nonessential amino acids
amino acids that the body can synthesize
Allergic reactions can result in
anaphylactic shock
Semivegetarian
avoid red meat but consumes other animal foods, including fish, poultry, eggs, and dairy products
When a protein is exposed to various conditions that cause it to alter its shape, the protein has undergon
denaturation
Protein Efficiency ratio (PER)
determined by measuring the weight gain of a growing laboratory animal that consumes a known amount of a specific type of protein
The two key factors in determining the quality of a protein are amino acid composition and its
digestibility
ovovegetarian
eats eggs for animal protein
vegan
eats only plant foods
PEM affects people whose diets lack
energy and protein
Denaturation
loss of normal shape of a protein due to heat or other factor
Personalized nutrition
making dietary choices based on one's genetic makeup, based on nutritional genomics
Biological value
measure of protein quality based on how well and how quickly the body converts food protein into body tissue proteins
Complementary combinations
mixtures of certain plant foods that provide all essential amino acids without adding animal proteins
to determine a person's RDA for protein
multiply his or her weight in kg by 0.8 g
Food intolerances
unpleasant physical reactions, including headaches and intestinal discomfort, after they consume nonprotein substances in foods such as lactose, monosodium glutamate, or sulfites
Secondary structure of the protein
reflects the polypeptide chain's coiling b/c of chemical attractions between certain component of the chain's amino acids
Gluten-free products are not always healthier as some are high in
sodium, simple sugars, fats
lactoovovegetarian
vegetarian who consumes milk products and eggs for animal protein
following digestion of proteins to amino acids,
the amino acids are transported by specific carrier systems into the absorptive cells
DNA
the hereditary material in a cell's nucleus that are in genes
Protein digestibility corrected amino acid score (PDCAAS)
the most commonly used tool to measure protein quality. Takes into consideration the essential amino acid composition of the protein, as well as how well the protein is digested and absorbed
Protein turnover
the process of breaking down old or unneeded proteins into their component amino acids and recycling them to make new proteins. Occurs constantly within cells
Tertiary structure
the protein's final three-dimensional form
Nutrigenetics
the study of how inherited genetic variations influence the body's responses to specific nutrients and nutrient combinations
Digestibility and amino acid composition of a protein
the two key factors in determining the quality of that protein
Limiting amino acids
they reduce the protein's ability to support growth, repair, and maintenance of tissues