nutrition-protein

Question 1

RDA protein

Answer 1

Table

Question 2

Define the term essential amino acids giving examples. TRY THis VIP MALL

Answer 2

a group of amino acids that humans cannot synthesise, thus it must be supplied from diet in sufficient amounts.

histidine
isoleucine
leucine
lys
meth
phenyl
threo
trypt
val

Question 3

Define PDCAAS (Protein Digestibility Corrected Amino Acid Score)/biological value of protein

Answer 3

method to evaluate protein quality based on the profile of EAA after correcting for the digestibility of the protein.
* The highest possible score:1.00
Quality of Proteins:
i- Complete Protein (PDCAAS=1)
▪Contain all essential amino acids
▪Animal sources
▪Soy protein
ii- Incomplete Proteins (PDCAAS < 1)
▪Lack one or more of the essential amino acids ▪Plant sources

Question 4

List the PDCAAS of egg albumin, milk protein and soy protein

Answer 4

egg- 1.00
milk- 1.00
soy-1.00

Question 5

Define the term limiting amino acids giving examples.

Answer 5

-the essential amino acids in digested protein that are in shortest supply relative to body requirements for protein synthesis.
- exp:Lysine, methionine, threonine and tryptophan TTM Ly
look at table
MCQ
Dietary protein must be supply at least 9 essential amino acid to prevent break down of protein.
* If an essential amino acid is missing, a cell may break down its own proteins to obtain it and protein synthesis will be limited.

Question 6

Explain mutual supplementation of proteins with examples

Answer 6

combination of two or more plant-food protein to provide the high-quality protein in the diets.
* yields complementary proteins that together contain all the essential amino acids in quantities sufficient to support health.
Exp:
* Wheat is deficient in lysine but rich in methionine.
* Beans is rich in lysine but deficient in methionine.
*If a mixture of wheat and beans is consumed it provides a protein with higher PDCAAS.

Question 7

Define the term nitrogen balance

Answer 7

the amount of nitrogen intake equals the daily loss through urine, sweats, and feces.

Question 8

Explain positive and negative nitrogen balance with conditions during which they occur

Answer 8

table

Question 9

Explain the protein sparing effect of carbohydrates.

Answer 9

Protein-sparing effect is having adequate dietary carbohydrate to
prevent the breakdown of protein for energy.
* When enough carbohydrate are ingested, proteins are spared to be used for their primary function. (build and repair tissue)
*But, when intake of carbs is low, proteins are breakdown into glucose for energy production by gluconeogenesis.