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NUTR 140 - Exam 3
Chapters 6, 7, and 10
73
Science
Undergraduate 1
12/01/2008

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Cards

Term
Protein Turnover
Definition
  • closely related to the ageing process
  • they are broken down and resynthesized
  • measured by the nitrogen balance
Term
Nitrogen Balance
Definition
to monitor protein intake
Term
Lacto-ovo-vegetarian
Definition
  • Includes: milk, eggs
  • Concern: Iron
Term

Protein-Energy Malnutrition

(types)

Definition
  • Marasmus
  • Kwashiorkor 
Term
How do you determine a person's protein requirement?
Definition
0.8 g protein/kg body weight recommended
Term
Protein Structure
Definition
  • Primary
  • Secondary
  • Tertiary
  • Quaternary
  • the primary is most important because it determines the protein's basic characteristics
Term
Denaturing Proteins
Definition
  • when a protein unfolds in unusual ways
  • denaturing agents:
    • physical agitation, heat, detergents, acids, bases, salts, alcohols, heavy metals.
Term
How many calories per gram of carbohydrates?
Definition
4 calories / gram
Term
How many calories per gram of protein?
Definition
4 calories / gram
Term
How many calories per gram of fat?
Definition
9 calories / gram
Term

Protein Synthesis:

Trascription

Definition
  • when mRNA writes a copy of the DNA
  • this is so it can be brought outside the nucleus
Term

Protein Synthesis:

translation

Definition
  • mRNA binds to a ribosome
  • tRNA reads the mRNA then builds a new protein
Term

Protein Synthesis:

Cell Signaling

Definition
  • when a protein or other compound in the cell membrane signals that transcription should be started or stopped
  • starting is called up-regulation
  • stopping is called down-regulation
Term
Hydrophilic Lipids
Definition
  • water-loving
  • Short- & medium-chain fatty acids
  • Transported into enterocytes without further assistance

 

Term
Hydrophobic Lipids
Definition
  • water-fearing compounds
  • Long-chain fatty acids, monoglycerides, lysophosphoipids, cholesterol
  • The longer the chain of the fatty acid the more solid it can be
  • Repackaged into micelle in lumen with assistance from bile then delivered into the mucosal sac

 

Term
Oils
Definition
lipids that are liquid at room temperature
Term
Fats
Definition
lipids that are solid at room temperature
Term
Alpha
Definition
  • the end of a fatty-acid that has the carboxylic acid group
  • a.k.a. the first carbon
Term
Omega
Definition
the end of a fatty acid that has the methyl group
Term
Saturated Fatty Acids
Definition
  • single carbon bonds
  • sources:
    • Animal Foods
Term
Monounsaturated Fatty Acids
Definition
  • Only one double bond
  • Sources:
    • Plant products
Term
Polyunsaturated Fatty Acids
Definition
  • has at least two double bonds
  • Sources:
    • plant products
Term
Trans Fats
Definition
  • Hydrogen atoms are on opposite sides of double bond (one on top and one on bottom)
  • Makes chain resemble saturated fat, while being unsaturated
  • Sources: hydrogenated oils/fats
  • Concerns: cause good cholesterol to go down and bad cholesterol to go up

 

Term
Essential Fatty Acids
Definition

Linoleic (ω-6)

Linolenic (ω-3)

Term
ω-3 Fatty Acids
Definition
  • linolenic acid
  • 18 carbons, 3 cis double bonds
  • dilation of blood vessels
  • Oils (soybean, safflower, corn, flaxseed)
Term
What is the dietary guideline for fats?
Definition
no more than 10% of total calories
Term
Hydrogenation
Definition
  • Process by which some carbon-carbon double bonds found in PUFAs are converted to single bonds
  • Produces trans fatty acids
    • Trans fatty acids cause good cholesterol to go down and bad cholesterol to go up
  • Reduces spoilage & improves texture
Term
Structure of Triglycerides
Definition

a molecule of glycerol with three fatty acids

Term
Structure of Phospholipids
Definition
  • very similar to triglycerides
  • instead of the third fatty acid they have a phosphate-containing polar lead group
  • They are amphipathic
    • contain both polar and non-polar portions

Term
Structure of Cholesterol
Definition
  • lipid class of sterols/sterol esters
  • multiring structures
  • weak polar compound

 

 

Term
Lipogenesis
Definition
  • the synthesis of fatty acids and triglycerides so they can be stored
  • happens when there is excess energy
Term
Lipolysis
Definition
the breakdown of triglycerides into fatty acids and glycerol in order to be used for energy
Term

Ketones

What are they?

When are they produced?: 

Definition
  • alternative engergy source formed from fatty acids
  • as a last resort for energy to be used by the brain, heart, skeletal muscles, kidney
Term
Adipocytes
Definition

a specialized cell that is part of the adipose tissue (fat tissue)

 

Term
What stimulates fat storage?
Definition
Energy excess → Insulin stimulates triglyceride storage → Lipogenesis (Synthesis of fatty acids & triglycerides)
Term
What stimulates fat breakdown?
Definition

  • Low levels of insulin during hypoglycemia
  • Exercise
  • Physiological stress
Term
Subcutaneous Fat
Definition

adipose tissue found directly under the skin

 

Term
ω-6 Fatty Acids
Definition
  • linoleic acid
  • 18 carbons, 2 cis double bonds
  • Makes arachidonic acid
  • inflamation
  • nuts and seeds
Term
Visceral Fat
Definition
surrounds the vital organs
Term
Lipoproteins
Definition
  • Spherical particle made of varying amounts of triglycerides, cholesterol, cholesteryl esters, phospholipids, proteins
  • The higher the content of triglycerides the lower the density
  • Transport lipids (hydrophobic substances around inside hydrophilic blood)
Term
Sources of Cholesterol
Definition
  • made from glucose and fatty acids
  • animal products
Term
Lipases
Definition
produced by the salivary glands that hydrolyze fatty acids from glyceral molecules (triglycerides)
Term
Micelles
Definition
  • Smaller stable lipid particles
  • Increase surface area of lipid
Term
What hormone stimulates the gallbladder?
Definition
Cholecystokinin
Term
Lipid Digestion
Definition

Phase 1: emulsification of lipids by bile

Phase 2: digestion of triglycerides by pancreatic lipase

Term
Nitrogen Balance
Definition
  • a way of measuring protein turnover
  • negative balance is bad
Term
Lacto-vegetarian
Definition
  • Includes: milk
  • Concern: Iron
Term
Vegan
Definition
  • Includes: no animal product
  • Concerns: calcium, zinc, iron, vitamin B12
Term
Marasmus
Definition
  • type of protein-energy malnutrition
  • All out starvation
  • skin and bones appearance
Term
Kwashiorkor
Definition
  • What the first child gets when the second child comes
  • Slight energy deficiency with significant protein deficiency
  • Puffed bellies

 

Term
Primary Structure of Proteins
Definition
  • Determined by DNA
  • Every proteins primary structure is unique, making it a unique molecule
  • determines the protein's major characteristics
  • one variation in this structure can cause serious disease
    • sickle cell anemia
Term
Secondary Structure of Proteins
Definition
  • the three-dimensional shape of the protein
  • created by +/- charges of the amino and carboxylic acid groups
  • form weak hydrogen bonds
  • most common structures
    • α-helix
    • β-folded sheets
Term
Tertiary Structure of Proteins
Definition
  • additional folding of the protein
  • due to R-groups
  • form disulfide bonds
    • very strong
    • distrupting them can ruin the structure
Term
Quarternary Protein Structure
Definition
  • several polypeptide chains that come together to form the final protein
  • only applies to proteins with more than one polypeptide chain
  • can also have non-protein parts called prosthetic groups
    • are essential to the protein's function
Term
Essential Water-Soluble Vitamins
Definition
  • Thiamin
  • Riboflavin (B2)
  • Niacin (B3)
  • Pantothenic Acid (B5)
  • Vitamin B6
  • Biotin
  • Folate
  • Vitamin B12
  • Vitamin C
  • Choline

 

Term

Niacin Deficiency

Definition
Pellagra
  • “Rough skin”
  • Four Ds
    • Dermatitis
    • Dementia
    • Diarrhea
    • Death
Term
Functions and Deficiencies of Vitamin B12
Definition
Coenzyme that catalyzes:
 

•    Production of succinyl CoA
•    Uses amino acids & fatty acids for ATP production
•    Conversion of homocysteine to methionine
•    Allows use of folate

 

Deficiency Conditions:

  • Pernicious anemia
Term
Function and Coenzyme of Thiamin
Definition
  • ATP production
  • Needed for the citric acid cycle
  • Synthesis of DNA and RNA
  • Nerve Function

Coenzyme: TPP

Term
Functions of Cholesterol
Definition
  • synthesize bile acids
  • component of cell membranes
  • help maintain fluidity
  • synthesis of steroid hormones
Term
Functions and Coenzyme of Folate
Definition
  • involved in the metabolism and interconversion of amino acids
  • conversion of homocystine
  • coenzyme - THF
Term
Functions of Niacin
Definition
  • Coenzymes catalyze redox reactions related to energy metabolism
  • Synthesizes fatty acids, cholesterol, steroid hormones, & DNA
  • Metabolizes vitamin C & folate
  • NAD+
    • Protein synthesis
    • Maintenance, replication & repair of DNAGlucose homeostasis
    • Cholesterol metabolism
  • Lower LDL & increase HDL
Term
Recommendations for Cholesterol
Definition
  • No DRI
  • U.S. Dietary Guidelines
  • Consume < 300 mg/day
Term
Deficiency Conditions of Vitamin C
Definition
Scurvy
Term
Function of Vitamin C
Definition
  • an anitoxidant that recharges enzymes by acepting and donating electrons
  • involved in the synthesis of carnitine
  • protection from free radical damage
  • enhances iron, copper, and chromium bioavailability

 

 

Term
Functions and Coenzymes of Vitamin B6
Definition
  • Coenzyme - PLP
  • involved in over 100 chemical reactions related to metabolism of proteins and amino acids via transamination
Term
Deficiency Conditions of Thiamin
Definition

Beriberi - "i can't, i can't"

dry, wet, infintile, cerebral

Term
Functions and Coenzyme of Riboflavin
Definition
  • converst vitamin A to folate
  • converts triptophan to niacin
  • forms vitamin B6 and K
  • Metabolism of important neurotransmitters
Coenzyme: FAD
Term

Deficiency Conditions of Riboflavin

Definition
Ariboflavinosis - weakness, sores of the lips, inflamation of the mouth, inflammed tongue, anemia, confusion
Term
Deficiency Conditions of Vitamin B6
Definition
microcytic hypochromic anemia - inadequate heme production
Term

Deficiency Conditions of Folate

Definition
macrocytic anemia
Term
VLDL
Definition
  • Made by liver
  • Contains large amounts of triglyceride
  • Delivers fatty acids to cells
  • More dense than chylomicrons
Term
LDL
Definition
  • “Bad” cholesterol
  • Delivers cholesterol to cells
  • Can increases build-up of plaque
  • High levels of LDL associated with increased risk for cardiovascular disease
Term
HDL
Definition
  • “Good” cholesterol
  • Lipoprotein made by liver that circulates in the blood to collect excess cholesterol from cells
  • Lowest lipid-to-protein ratio
  • Reverse cholesterol transport
  • Salvages excess cholesterol from cells
  • Transported back to liver
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