[3] PROTEIN Flashcards
- Fundamental structural unit/elements of every cell of the body
- Essential for normal growth and development and maintenance of health
Protein
Protein
From GREEK word (1) “____” meaning (2) ____
(1) proteios
(2) “of first” or “primary”
Protein
- Has extremely complex molecules containing:
(1) ____ - Only nutrient group that contains (2) ____
- Composed of chemical compounds called (3) ____
(1) C, H, O, N S, Fe, P, I, Cu
(2) nitrogen (16%)
(3) amino acids
- Chemical compounds which make up proteins
- Building blocks of all proteins
Amino Acids
Amino Acids
Assembled in the body to form specific ____
tissue protein
Amino Acids - Examples
- (1) ____ in the connective tissues
- (2) ____ in muscles
- (3) ____ in hemoglobin
(1) Collagen
(2) Myosin
(3) RBC
Classification of Amino Acids
Amino acids not manufactured by the body and are obtained only from the food we eat.
Essential Amino Acids
Examples of Essential Amino Acids
Histidine
Phenylalanine
Lysine
Threonine
Valine
Isoleucine
Leucine
Methionine
Tryptophan
Classification of Amino Acids
Can maintain life processes for adults but not enough for normal growth in children (essential only for children)
Semi-essential Amino Acids
Example of Semi-essential Amino Acids
Arginine
Classification of Amino Acids
Amino acids which are synthesized/manufactured by the body so they are not essential in the diet
Non-essential Amino Acids
Examples of Non-essential Amino Acids
Alanine
Aspargine
Aspartic Acid
Cystine (Cysteine)
Glutamic Acid
Glutamine
Glycine
Hydroxylysine
Proline
Serine
Tyrosine
Functions of Protein
- ____ & ____
- Essential for ____
- Provides ____
- ____
- Body building & repair tissue
- Essential for growth
- Provides energy
- Regulator of body processes
Recommended Energy & Nutrition Intakes (RENI) - Protein
Standard:
* (1) ____ desirable body weight for normal adult
Based on caloric requirement:
* (2) ____ of total calories consumed in a day
(1) 1 gm/kg
(2) 10-15%
Ways of Improving Protein Quality
Adding micronutrients to foods to ensure that minimum dietary requirements are met
Fortification
Ways of Improving Protein Quality
Vitamins or minerals have been added to the food
Enrichment
Ways of Improving Protein Quality
A preparation intended to provide nutrients that may be missing or may not be consumed in sufficient quantity in a person’s diet
Supplementation
Ways of Improving Protein Quality
Any protein that is incomplete on its own but may become complete when combined with other proteins to provide all of the amino acids necessary for normal metabolism
Complementation
Digestion of Protein
- (1) ____ to make it more susceptible to the action of enzymes
- HCl coverts (2) ____ to ____.
- (3) ____ begins to break down proteins into smaller polypeptides & some amino acids.
(1) Stomach acid with the aid of HCl
(2) pepsinogen to the enzyme pepsin
(3) Pepsin
Digestion of Amino Acids
- Bulk of protein digestion takes place in the (1) ____
- (2) ____ are responsible for breaking down proteins into simpler substances (tripeptide, dipeptides, & amino acids).
- Enzymes located on the surface of the intestinal wall, (3) ____, complete the digestive process
(1) small intestine
(2) Pancreatic enzymes (trypsin, chymotrypsin, & carboxypeptidase)
(3) aminopeptidase & dipeptidase
Absorption of Proteins
- Takes place in the (1) ____ of the small intestine through (2) ____
- (3) ____ release amino acids into the bloodstream for transport to the (4) ____
(1) mucosa
(2) active transport
(3) Intestinal cells
(4) liver
Liver Functions Related to Protein Metabolism
- It uses the (1) ____ & ____.
- It retains amino acids to make (2) ____, ____, & ____
- It regulates the release of (3) ____ and removes ____ from the circulation
- It regulates (4) ____
(1) amino acid that it needs & releases those that aren’t needed elsewhere
(2) liver cells, non-essential amino acids, & plasma protein
(3) amino acids into the bloodstream and removes excess amino acids
(4) energy metabolism
Metabolism of Proteins
A constant two-part process:
1. ____ - proteins are broken down by the body into amino acids.
1. ____ – amino acids are resynthesized into tissues as needed.
This is a continuous conversion needed to maintain (3) ____ within the body.
(1) Catabolism
(2) Anabolism
(3) overall protein balance
Index of the amount of CHON utilized by the body & how well body tissues are being maintained
Nitrogen Balance
Nitrogen Balance
Nitrogen intake from CHONs must be equal to the ____
nitrogen output in urine & feces
Nitrogen Balance
Occurs when the body takes in more nitrogen than it excretes = tissue building
Positive Nitrogen Balance
e.g. infancy, pregnancy & lactation, childhood and adolescents
Nitrogen Balance
Occurs when the body takes in less nitrogen than it excretes = More tissues are broken down than built
Negative Nitrogen Balance
e.g. Malnutrition, emotional stress, illness, surgery, shock, immobility and severe pain
Problems Related to Protein Intake
Develops when there is an inadequate supply or intake of protein e.g. in case of famine, poverty and inadequate food supply
Kwashiorkor (Protein Deficiency)
Kwashiorkor (Protein Deficiency)
Manifestations: accumulation of (1) ____, (2) ____, painful skin lesions, changes in the (3) ____, and (4) ____
(1) fat in the liver
(2) edema
(3) pigmentation of skin and hair
(4) muscle wasting
Problems Related to Protein Intake
- Resulting from severe malnutrition
- Afflicts young children and adults who lack both energy and protein foods as well as vitamins and minerals
Marasmus (Protein Energy Malnutrition)
Marasmus (Protein Energy Malnutrition)
Appears (1) ____ but does not have (2) ____, hair is (3) ____, and the skin is (4) ____
(1) emaciated
(2) edema
(3) dull and dry
(4) thin and wrinkled
Problems Related to Protein Intake
May contribute to:
* Heart disease
* Colon cancer
* Osteoporosis due to Ca depletion
Protein Excess
Protein Excess
Puts more demands on the (1) ____, converting (2) ____ to ____, and the (3) ____ to excrete excess urea as in the case of (4) ____
(1) liver
(2) nitrogen to urea
(3) kidneys
(4) ketosis
Effects of Imbalance
- (1) ____
- Increased (2) ____
- Loss of (3) ____ leading to impairment of body function
(1) Growth retardation
(2) susceptibility to infection
(3) muscle tissue
