Nutrition and Supporting Sciences Flashcards
what is energy?
the capacity to do work
___, ___, and ___ all yield energy
CHO, protein, and fat
___ and ___ provide 4 calories/gram
CHO and protein
CHO and protein provide ___ calories/gram
4
___ provides 9 calories/gram
fat
fat provides ___ calories/gram
9
the brain uses ___ exclusively as an E source
glucose
the brain uses glucose exclusively as an ___
E source
what does the brain use as an E source during starvation?
ketone bodies
where are tissue stores of glucose in the body
- glycogen in muscle and liver
- fat from adipose tissue
- cellular mass (protein stores)
glucose is stored in the ___ and ___ as glycogen
muscle; liver
glucose is stored in the muscle and liver as ___
glycogen
what is gluconeogenesis
conversion of non-carbohydrate sources into glucose; creation of glucose from glycerol and amino acids
what is homeostasis
state of equilibrium of the internal environment of the body
what are enzymes
proteins; organic catalysts that control reaction
what is a conenzyme
enzyme activators; includes some vitamins (B)
what vitamins are needed for E production?
pantothenic acid, thiamin, riboflavin, and niacin
what is a substrate
substance upon which an enzyme works
what is a cofactor
assists enzymes; minerals
what are hormones?
secretions from endocrine; trigger enzyme action; chemical messengers that trigger enzymes
what does thyroxine regulate
metabolism and rate of oxidation
thyroxine influences what
physical and mental growth
what happens when glycogenolysis and gluconeogenesis of the liver is stimulated
raises the blood glucose
what is anabolism
synthesis of a more complex substance
what is catabolism
breakdown; uses and releases energy; creates a constant energy deficit, which must be supplied by food
what is BEE
basal energy expenditure; minimum amount of energy needed at rest in fasting (amount needed to carry out involuntary work of the body, activity of internal organs, and internal temp)
BEE is affected by what?
extremes in environmental temperatures; tropical climate 5-20% increase
what stimulates metabolic rate and by how much?
caffeine, alcohol, and nicotine; 7-15%
what is EEPA
energy expended in physical activity; highly variable
what is TEF
thermic effect of food, diet-induced thermogenesis, the calorigenic effect of food; energy needed to digest, absorb, and assimilate nutrients; ~10% of E expenditure
TEF is greater or less after consumption of carb and protein than after fat
greater
TEF is about ___% of E expenditure
10%
what is BMR
basal metabolic rate; measured in morning when reclining, awake, relaxed, at normal body temp, at least 12 hrs after meal, and several hours after strenuous activity
BMR measures
oxygen consumed
BMR is affected primarily by what 4 things
- sex
- age
- body composition
- endocrine glands-thyroid
how is BMR affected by sex
women have 5-10% lower BMR than men
how is BMR affected by age
highest BMR is 0-2 years of age; older adults less activity, less lean body mass, more body fat: BMR decreases
how is BMR measured
by PBI/protein bound iodine; measures activity of thyroid gland, metabolism, level of thyroxine priduced
when PBI is elevated, BMR is ___
elevated
is PBI a nutritional assessment parameter?
no
BMR can be increased by ___
exercise
what is BEE
basal energy expenditure; calculated BMR
BEE includes what
age, sex, body surface area (height, weight)
what is rmr?
energy expenditure measured under similar conditions, after a short rest and controlled intake of caffeine, alcohol
___ is more frequently measured than BMR
RMR
RMR is ___ than BMR by ___%
greater; 10-20%
of the predictive equations ___ predicts within 10% of indirect calorimetry
Mifflin St Jeor
Mifflin St Jeor should be used with ___ and ___ individuals
normal weight and obese individuals; use actual body weight for underweight, overweight, and obese
what is the most practical way of measuring energy balance
following changes in weight
RQ depends on what
fuel mixture being metabolized: cho alone: 1 mixture: 0.85 protein alone: 0.82 fat alone: 0.7
list the monosaccharides
glucose, fructose, galactose
list the disaccharides
sucrose, lactose, maltose
what 2 monosaccharides is sucrose made of
glucose and fructose
what 2 monosaccharides is lactose made of
glucose and glucose
what 2 monosaccharides is maltose made of
glucose and galactose
list the polysaccharides
- starch
- cellulose
- glycogen
- dextrin
- pectin
what is starch
glucose chains, 50% of CHO intake
what is cellulose
resistant to digestive enzyme amylase; adds bulk
what is glycogen
animal starch; from glucose; stored in muscle and liver
what is pectin
nondigestible; thickening quality; in fruits
what is dextrin
intermediate product of starch breakdown
what is sorbitol
alcohol from glucose; absorbed by passive diffusion; converted into fructose
how sweet is fructose
the sweetest
how sweet is sorbitol
slightly less sweet than glucose
put the following in order of sweetness: sucrose, sorbitol, glucose, fructose, invert sugar, lactose, galactose, maltose, mannitol
- fructose
- invert sugar
- sucrose
- glucose
- sorbitol
- mannitol
- galactose
- maltose
- lactose
what is the make up carbohydrates
made of carbon, hydrogen, and oxygen
what are the functions of cho
energy, protein-sparing action, regulation of fat metabolism
sulfur is found in what proteins
cystine, cysteine, and methionine
what make up protein
carbon, hydrogen, oxygen, and nitrogen; sulfur in cystine, cysteine, and methionine
what % of a protein is nitrogen
16%
amino acids have a ___ and a ___
amino group (NH2) as acid; carboxyl group (COOH) as the acid
**what are the essential amino acids
TV TILL PMH; threonine valine tryptophan isoleucine leucine lysine phenylalanine methionine histidine
what are the 2 conditionally essential amino acids
arginine
glutamine
tryptophan is a precursor for ___ and ___
seratonin; niacin
___ is converted to tyrosine
phenylalanine
phenylalanine is converted to ___
tyrosine
methionine is converted to ___
cysteine
___ is converted to cysteine
methionine
what is a conjugated protein
simple plus non protein substance (like lipoprotein)
what is a simple protein
yields only amino acids
what is a derived protein
fragments from simple and conjugates (like peptide)
what are the functions of protein
- tissue synthesis
- maintains growth
- regulated body processes
why is protein an inefficient energy source
nitrogen must be removed first; 58% of protein can be converted to gluose
what are the diet requirements for protein
0.8 g/kg body weight; 10-15% of total E intake
legumes are low in what amino acids
methionine, cystine, and tryptophan
gelatin is low in what amino acids
methionine and cystine; has NO tryptophan
most food fat is a ___
triglyceride
triglycerides are ___ fats; made of ___ and ___
simple; 3 fatty acids and 1 glycerol
where are phospholipid found
cell membrane
what is a compound fat
simple plus other component (like a phospholipid)
what is a derived fat
derived from simple or compound by fat hydrolysis or enzymatic breakdown (like fatty acid, glycerol, steroid)
what are examples of a derived fat
fatty acid, glycerol, steroid
what are saturated fatty acids
all available bonds of carbon dioxide are filled with hydrogen; solid and hard at room temp
what is an unsaturated fatty acid
one or more double bond
**___ is the most polyunsaturated
safflower oil
**___ is the most unsaturated
canola oil
**linoleic acid is omega ___
6
**what is the best source
safflower oil
**a deficiency in linoleic acid does what
creates eczema, poor growth rate, petechiae
**if linoleic acid replaces CHO
LDL decreases, HDL increases
**if linoleic acid replaces saturated fat
cholesterol decreases, HDL decreases
EPA and DHA are what type of omega
3
EPA mainly comes from
fish
DHA comes mainly from
walnut, flaxseed, and canola oil
omega 3 have what effect on cholesterol levels
little; decreases hepatic production of triglycerides (inhibit VLDL synthesis)
omega 3 is involved in ___
retinal function and brain development
what does omega 3 deficiency result in
neurological changes-blurred vision, numbness
what is the structure of fatty acids
straight hydrocarbon chain ending in a corboxyl (COOH) group at one end and a methyl group (CH3) at the other
how are fatty acids classified
- number of carbons
- position of first double bond
- number of double bonds
what is designated by the omega sign
location of the first double bond counted from the METHYL end
what is the structure of linoleic acid
C18:2omega6
what is the structure of linolenic acid
C12:3omega3
linoleic acid is omega ___
6
linolenic acid is omega ___
3
in terms of fat, what is hydrogenation
process of adding hydrogen at the double bond of unsaturated fatty acids to increase saturation and stability
in trans fatty acids the hydrogens are found ___ from each other
across from each other; harmful to cell function
trans fats are found in milk fat, ___%
4-8%
___, ___. and ___ contain trans fats as a product of partial hydrogenation of PUFA
margarine, shortenings, frying fats
**what is the most saturated
coconut oil
list the following in order from most to least saturated fat: palm oil, palm kernel, cocoa butter, coconut, canola, butter
coconut, palm kernel, cocoa butter, butter, palm oil, canola
Medium chain triglycerides have how many carbons
6-12
where are MCTs found
milk fat, coconut oil, palm kernel
list the following in order from most to least MUFA: coconut, sunflower, peanut, kernel, olive
olive, canola, peanut, sunflower, coconut
what has the most MUFA
olive oil
what has the most PUFA
safflower oil
list the following in order from most to least PUFA: cottonseed, soybean, safflower, p;am kernel, sunflower
safflower, corn, soybean, cottonseed, sunflower, palm kernel
list the following from most to least for butter: MUFA, PUFA, sat
sat, pufa, mufa
list the following from most to least for margarin: MUFA, PUFA, sat
pufa, mufa, sat
how does fat delay gastric emptying
depresses gastric secretion
why does fat provide more energy than CHO
has less oxygen and more carbon; more carbon atoms for oxidation
what are the diet requirements for fat
less than 30% kcals
how is alcohol metabolized
as a fat; 7 g/kcal
how do you determine calories from alcohol?
(.8)(proof)(ounces); proof=(%alcohol)(2)
how is proof calculated
(% alcohol)(2)
**what is winterized oil
treated so won’t crystallize when cold (salad dressings)
**how is winterized oil made?
oil chilled to 45 degrees; fatty acids with high melting points crystallize and are filtered out
**what is the appearance of winterized oil
clear NOT cloudy
**what are some oils that have are winterized
corn, soy, cottonseed; NOT olive
how much insensible water is lost each day
0.8-1.2 litres
how do you calculate mEq
(mg/atomic wt)*valence
what are the atomic weights and valances of Na+, K+, and Ca2+
Na+: 23, 1
K+: 39, 1
Ca2+ :40, 2
what are extracellular electrolytes
- Na; sodium
- Ca; calcium
- Cl; chloride
- HCO3; bicarbonate
sodium chloride is ___% sodium
40%
one tsp of salt has ___g of NaCl
6g
sodium is reabsorbed by ___ and retained by ___
aldosterone; steroids
what are intracellular electrolyes
- K; potassium
- Mg; magnesium
- P; phosphorus
what are sources of potassium
meat, fruits, veg; banana, orange, tomato, potato, cantaloupe
potassium excretion is increased by ___
aldosterone
hypercalemia causes ___
cardiac irregularities
**what is the normal range for sodium
136-145 mEq/L
what is the normal range for potassium
3.5-5 mEq/L
what is the normal range for calcium
4.5-5.5 mEq/L
what is the normal range for magnesium
1.5-2.5 mEq/L
what is the normal range for chloride
96-106 mEq/L
what is the normal range for phosphorus
3-4.5 mEq/L
what is the effect of protein of fluid balance
exerts osmotic pressure
what is the function of albumin
exerts pressure on blood vessel wall that keeps water within; when alb drops, pressure drops, causing fluid to leak out-water moves from extracellular to interstitial space (edema)
what happens when albumin is low
when alb drops, pressure drops, causing fluid to leak out-water moves from extracellular to interstitial space (edema)
low serum protein leads to ___ and ___
edema and ascites
what is anasarca
extreme, generalized edema and widespread swelling of the skin due to effusion of fluid in extracellular space
anasarca is associated with what?
heart, liver, renal failure, and extreme protein/calorie malnutrition
a serum albumin of ___ is often associated with physical signs of fluid retention
2.8
**what are the symptoms of dehydration
nausea, dizziness, sunken eyes, fever, hyperventilation, excessive sweating, concentrated urine, dry inelastic skin, increase in solutes (BUN), tachycardia, headache, fatigue, decreased appetite, and rapid weight loss
what is the best assessment parameter for fluid status
serum sodium
___ releases hydrogen ions
acid
___ takes up hydrogen ios
base
what is a buffer?
mixture of acid and base components to protect against a strong acid or strong base
what is a major extracellular buffer
combination of carbonic acid and sodium bicarbonate
the pH scale measures what
hydrogen ion concentration
lungs control supply of ___ to help with acid base balance
carbonic acid; hypoventilation retains acid and hyperventilation loss of acid
kidneys control supply of ___ to help with acid base balance
bicarbonate (base); excrete excess bicarbonate and level of base decreases
**a change in one side of the buffer brings about a ___ in the other side to ___
compensatory change; maintain balance, pH close to 7.4
in acid-base balance, a failure related to the pulmonary system is
respiratory
in acid-base balance, a failure related to the kidneys is
metabolic
- *what do the following tell you and what are the normal values:
1. HCO3 (bicarb)
2. pCO2 (carbonic acid)
- tell you if kidneys working; 24-28
2. tell you if lungs working; 35-45
**what is the function of vitamin A
skin, vision
**what are sources of vitamin A
yellow, orange fruits; dark green leafy vegetables; cantaloupe, fish, liver, carrots, fortified skim milk, apricots, sweet potato
**what are signs of vitamin A deficiency
night blindness, nyctalopia, xeropthalmia, bitot’s spots, hyperkeratosis
**what is the earliest sign of vitamin A deficiency?
nyctalopia, reversible
**what is a sign of vitamin A deficiency that appears when deficiency is severe and prolonged
xeropthalmia -corneal damage, not reversible
**what is one of the least toxic vitamins
E
**what is the function of vitamin E
antioxidant; resists hemolysis of RBC
what are sources of vitamin K
spinach, kale, broccoli, green leafy vegetables
what vitamin is lost in cooking as temp of ph rises but is stable in acidic solution
b1 aka thiamin
what is the function of b1/thiamin
oxidation of CHO; increase CHO increased need for b1; metabolism of pyruvate
what are sources of b1/thiamin
grains, wheat germ, pork, liver
what are signs of b1/thiamin deficiency
beriberi, muscle weakness, foot drop, memory loss tachycardia, decreased erythrocyte transketolase, increased plasma pyruvate
what is the name for vitamin b1
thiamin
what is the name for vitamin b2
riboflavin
what are signs of b2/riboflavin deficiency
cheilosis (cracked lips), angular stomatitis (mouth corner cracks, sore throat), and magenta tongue
what are sources of folate
fortified dry cereal, liver, kidney, green leafy vegetables, citrus fruits, lentils, beans
what is the name for b6
pyridoxine
what is the name for b12
cyanocobalamin
an increase in protein requires an increase in what vitamin
b6/pyridoxine
what is the most abundant mineral
calcium
what mineral is regulated by the parathyroid hormone
calcium
what aids calcium absorption
vitamin D, acid, lactose
what lowers serum calcium and how
calcitonin by inhibiting bone resorption
what are the functions of calcium in the body
blood clotting, cardiac function, nerve transmission, smooth muscle contractility
what are sources of phosphorus
meat, milk, poultry, eggs, fish, cheese
what is the absorbable form of iron
ferrous (stored form is ferritin)
what are signs of copper deficiency
rare: microcytic anemia, neutropenia
what is Wilson’s disease
low serum copper, genetic absence of liver enzyme
what are sources of sulfur
meat, fish, eggs, poultry
what are the 2 minerals required in glucose metabolism
chromium and zinc
as E expenditure of the body increases, the need for ___, ___, ___, and ___ also increase
thiamin, niacin, riboflavin, and pantothenic acid