Final Quiz Questions Flashcards
Common limitations of observational studies
They can rarely establish causal relationships
Unit of energy density
kcal/g
Essential nutrients are ____ for health
Necessary but not sufficient
24 hour dietary recall is a ___ dietary assessment tool
Retrospective
Study was conducted to collect relevant info (exam scores, gender, major, attitude) from the same group of students for 10 years after completion of the course
What type of study is it
Prospective cohort
Strongest evidence to reject hypothesis that pellagra was germ based
Dr Goldberger exposed healthy individuals to bodily fluids of those with pellagra
None of them developed pellagra
Hypothesis from orphan experiment from Dr Goldberger
Orphans were fed nutritious diet and eventually recovered from pellagra
Nutritious diet is sufficient to cure pellagra
Essential nutrient cannot be
Made in sufficient quantities by the body
Average = 200 mg/day
SD = 20
What is the RDA
240
200 + (2*20)
Aldo monosaccharides
Glucose
Galactose
D fructose
Part of sucrose
Rich in corn syrup
Very sweet
Levulose
Why is it important to include omega 6/3 fatty acids in the diet
They are precursors of eicosanoids
The human body is unable to synthesize them because the cells can’t create double bonds between the CH3 and 9th carbon
They serve important roles that can’t be compensated fully by other nutrients
T/F
Humans don’t have the enzyme required to break beta 1-4 glycosidic bonds in lactose
False
Polysaccharides
Amylose and amylopectin have alpha 1,4 bonds
Glycogen is found in the liver and muscle. It has more branches than amylopectin
Liver glycogen contributes to the maintenance of blood glucose
Long chain fatty acids
saturated
Solid at room temp
Short chain fatty acids
saturated
Liquid at room temp
Medium chain fatty acids
Saturated
solid or liquid at room temp
T/F
Diverticula are polyps and are a precursor to colon cancer
False
Soluble fiber
Promotes satiety by delaying gastric emptying
Can protect against diabetes by preventing the rapid increase of blood glucose post meal
T/F
TGs can cross the cell membrane on their own
False
Rank relative sweetness of sugars
Sucrose > glucose > galactose > lactose
Proteins are the body’s main source of
Nitrogen
Semi essential AA
Cysteine from methionine
Tyrosine from phenylalanine
Essential AA
Valine is an example
Body does not contain enzymes to produce them
Obtained from the diet
T/F
All proteins have an amino + carboxyl group
True
Proteins
Heat, acid, salt, base can denature them
Tertiary structure determined by R group interactions
Proteins are AA joined by peptide bonds
Proteins have many functions: growth, enzymes, hormones, antibodies, energy, acid base balance
Why do you subtract 2 in the nitrogen balance equation
Account for N loss in other routes
Fecal/skin
Lipoprotein that transports diet derived lipids from the small intestine through lymphatics into bloodstream
Chylomicrons
Lipoprotein that is derived from VLDL as TGs are removed
LDL
Synthesized in the liver and intestine
Lipoprotein that picks up cholesterol for excretion
HDL
Synthesized in the liver to carry lipids and cholesterol to other tissues
VLDL
Emulsifiers ex
Lecithin
Polysorbate 60
Phosphatidylcholine
Egg yolk
Monoacylglycerol
T/F
Lipoprotein lipase is activated by insulin and acts on chylomicrons and VLDL
True
PKU
Affected individuals can’t make tyrosine
Treatment involves diet low in Phe
Toxic byproducts that build up cause severe retardation
Nutrient that starts its chemical breakdown in the mouth
Carbs
Primary function of the epiglottis
Block larynx and protect airway during swallowing
Stomach
Secretes protease
Releases chyme in small portions through the pyloric sphincter to the SI
Secretes HCl to aid digestion and absorption
Churns, mixes, and grinds food to produce chyme
Muscles in digestive system
Segmentation
Peristalsis
Sphincter contractions
Most digestion and absorption occurs in
The SI
Glucose is taken up by enterocytes through ___
Fructose is taken up through ___
Active transport
Facilitated transport
Epithelial cell that secretes mucin
Goblet cells
Water soluble nutrients are absorbed across enterocytes, released into the ___, delivered to the ___ through the ___
Blood
Liver
Portal vein
Secretion and motility functions of digestive system coordinated by
Hormonal system
Nervous system
Enzymes for:
Starch
Dextrins
TG
Protein
Pancreatic amylase
Isomaltase
Lipase
Pepsin
Biological sensation that prompts individuals to stop eating
Satiation
Class of nutrients with the largest difference btwn gross and metabolizable NRG
Vitamins
Satiety hormone released from adipose tissues
Leptin
Component of NRG expenditure that is modulated by macronutrient content
Thermic effect of food
Orlistat works by
Decreasing digestible NRG of food consumed
Decine in NRG needs associated with age is more pronounced in men than women
True
Planning diet for hospitalized patient who has been bedridden
How to access caloric needs
Indirect calorimetry
Insulin decreases blood glucose by
Increasing uptake in adipose
Increasing uptake in muscle
Increasing lipogenesis in adipose
Increasing glycogenesis in liver
Alcohol in red wine consumed with T bone steak, sweet potato, and marshmallow will undergo
Glycolysis
Without taking insulin, metabolic activities of type 1 diabetes are similar to
Those who are fasting
Beta oxidation of long chain FA
Generates reducing equilivants
8 Acetyl CoA are produced from a 16 C FA
Highly active after a breakfast of bacon, eggs, and sausages
Requires NAD and FAD
FA can be synthesized from C skeletons of
AA
Glucose
Acetyl CoA
Ethanol
Failure of ___ leads to high ammonia in the blood
Liver
Gluconeogenesis
Requires NRG
During glycolysis
Glucose is converted to 2 pyruvate
Uncoupling protein allows H+ to bypass ATP synthase
Overexpression
Increases NRG expenditure
Glycogenesis
Is stimulated by insulin
B vitamins have a major role in
NRG metabolism
Disease from prolonged thiamin deficiency
Beriberi
Best source of riboflavin
Liver
Niacin
Niacin flush is a pharmacological side effect from taking large doses of supplemental niacin
RDA is expressed in mg of niacin equivalents
Deficiency can lead to dermatitis
Vitamin B6
B6 is stored in muscle tissue
B6 helps with carb, FA, and AA metabolism
Alcohol contributes to destruction of B6 in the body
Deficiencies that lead to megaloblastic anemia
Folate
B12
High intakes of folate mask
B12 deficiency
Fortification of grain products with folate reduces risk of
Neural tube defects
Macrocytic anemia
Group most at risk for developing B12 deficiency
Older adults
Fat soluble vitamins
Deficiency symptoms take a long time to develop after insufficient ditary intake
Can be toxic at high levels
Night blindness
Due to low levels of retinal in the eyes
First sign of vitmain A deficiency
Inability to see in dim light or darkness
Rich source of retinoids
Beef liver
An animal raised on retinoic acid as its only source of vitamin A
Becomes blind
Dietary intake to storage of Vitamin A for vegans
Provitamin A
Retinal
Retinol
Retinyl ester
Final step of vitamin D activation occurs in
The kidney
Vitamin D deficiency leads to
Rickets in children
Osteomalacia in adults
Vitamin D promotes
Calcium and phosphorous absorption
Naturally occuring food sources of vitamin D
Beef
Salmon
Features shared by vitamin A and D
Require dietary fat for absorption
Can cause toxicity
Function like a hormone
Regulate gene expression
Electrolytes
Sodium is paired with Cl in extracellular fluid
Sodium is the main extracellular cation
Excess movement of water out fof cells causes dehydration
Fluid movement into/out of capillaries
Fluid absorbed into capillaries on venous side
Controlled by albumin concentration
Filters fluid out of capillaries on arterial side
Water consumption
Overconsumption may be lethal
Increases during prolonged heavy exercise
Consume 1 mL of water per Kcal burned per day
Occurs by eating low fat solid foods
During prolonged heavy exercise
Water is lost through sweating and breathing
ADH release is increased
Mineral nutrients
I
Se
Mg
Mn
Cu
DRIs of calcium and iron
UL calcium > RDA iron
UL calcium > UL iron
Individual more likely to have osteoblast activity
1 year old
blood glucose and glucagon : blood calcium and
parathyroid hormone
T/F
Blood calcium is a good indicator of calcium status
False
Increase calcium absorption
Vit D
Pregnancy
Lactose
Stomach acid
Bioavailability
Amount of a nutrient absorbed and ready to be used by the body
Almost all the Ca2+ in the body is used to
form Hydroxyapatide
When blood calcium is low
Resportion from bones increases
PTH is released
Reabsorption from kidney increases
Absorption from intestine increases
Carries iron through the blood to tissues
Transferrin
When iron levels are low
IRPs bind to IREs
Insulin/glucose : ___/iron
Hepcidin
Ferroportin facilitates
Cellular iron export
DMT transports
Reduced nonheme iron
Other 2+ ions
Ferroxidase contains
Copper
Incidates iron deficiency
High total iron binding capacity
Low serum ferritin
Low transferrin saturation
Mutations that lead to hemochromatosis
Mutations leading to impaired function of hepcidin
Iron RDA
Adolescent female > adult male
Pregnant women > postmenopausal women
Early indicator of iron depletion
Serum ferritin
Zinc/MT : iron/____
Ferritin
Iron/hepcidin : calcium/__
Calcitonin
Selenium
Part of endrogenous antioxidant system
Function of iron
Required for NRG metabolism
Involved in synthesis of neurotransmitters
Cofactor of enzymes in redox reactions
Oxygen carrier
Response to declining zinc status in expression of Zip 4
Increase
Copper homeostasis
Excessive copper can be excreted into bile
Copper can bind to MT
Iodine
Essential component of T3 and T4
Iodine deficiency causes goiter
Maternal iodine deficiency can result in increased risk of cretinism
Seaweed is a rich source
Flouride
Can substitute for the hydroxyl group of hydroxyapatite
Iron absorption
Consumtion of animal tissues enhances it
Increased requirements enhance it
Vit C enhances it
Gastric acid enhances it
Zinc
Excessive Zn causes copper deficiency
Zn supplementation induces expression of MT
Fe, Cu, Zn compete for intestinal absoroption
Nutrigenetics
The study of how genetic makeup modulates response to diet
Nutrigenomics
The study of how what you eat modulates expression of genes
Epigenetics
The study of heritable changes in phenotype caused by changes in gene expression that do not involve changes to the DNA sequence
Metagenomics
the study of genetic material from a mixed community of organisms
Microbiome
The combined genetic material of microorganisms in a particular environment
Microbiota
the microorganisms of a particular environment
Prebiotics
are the non-digestible food ingredients that stimulate the growth/activity of bacteria in the digestive systems in ways beneficial to health
Probiotics
live microorganisms that are intended to have benefits when consumed or applied to the body
What factors regulate the distribution adn compostion of gut microbiota
Antimicrobial peptides
Mucus
Gastric acid
O2 tension
GI secretion
GI motility
Synbiotics
Diet
Homocysteine
B9/12
Create Met
B6
Covert homocysteine to cys
