protein in the diet and its metabolism Flashcards
what are proteins made up of ?
20 amino acids
amino acids consists of a carbon atom bound to what 4 groups?
hydrogen
nitrogen
oxygen
carbon
what bonds hold the structure of proteins
peptide bonds
what is the primary structure of proteins
peptide bonds
NH3+ groups terminal end
other end has a free carboxyl group
amino acids
at a high pH are carboxylic acids charged or uncharged and amines?
carboxylic acids are charged
amines are uncharged
what polypeptide chains make up
proteins
recommended intake of protein is …
10-35% pf daily energy intake
how do you calculate the recommended intake of protein
converted pounds to kg
multiply kg by 0.8 to get your RNI in g/day
where does chemical digestion begins
the stomach
what is the 3 step process of chemical digestion
hydraulic acid (HCL) denatures (uncoils) proteins
HCL activated pepsin (enzyme)
pepsin breaks peptide bonds leaving shorter polypeptide
where does chemical digestion occur after the stomach and where does it go to further break down
small intestine
pancreas enzymes in the microvilli of the intestine further break down polypeptides for absorption
the body needs what …
nitrogen balance
what is a conditionally essential amino acid
when a nonessential amino acid becomes essential under certain circumstances, it is known as conditionally essential
if the diet fails to provide phenylalanine, or the person has phenylketonuria (PKU), then tyrosine becomes…
conditionally essential
what is protein-energy malnutrition (PEM)
a condition characterised by loss of muscle and fat mass and an increased susceptibility to infection that results form the long-term consumption of insufficient amounts of energy and protein to meet the body’s needs
