Macronutrition Flashcards
excess carbohydrates are converted to (2)
- glycogen
- triacyglycerol
What is the major energy source for humans?
carbohydrates
1 gram of carbs is how many kcal?
4 kcal
simple carbs
monosaccharides
- glucose
- fructose
- galactose
simple carbs
disaccharides
- sucrose
- lactose
- maltose
complex carbs
polysaccharides
* many ___ linked together in chains
* ___ in animals, and ___ and ___ in plants
- monosaccharides
- glycogen, starch, fiber
What is the most important carbohydrate fuel for the body?
glucose
T or F: glucose rarely appears are a monosaccharide in food.
True
part of a disaccharide or starch
T or F: fructose causes a great rise in blood glucose but not blood lipids.
False; fructose increases blood lipids but not blood glucose
high fructose corn syrup is suggested to be the cause of increased ___ and ___
diabetes and obesity
Digestion of carbohydrates
α-Amylase
* ___ starch and glycogen to ___ and ___
* exists in ___ and ___ juice
- hydrolyzes, maltose, maltotriose
- saliva and pancreatic
enzymes on the ___ surface of the small intestine
1. maltase “___:” maltose and maltotriose → ___
2. sucrase: sucrose → ___ and ___
3. lactase: lactose → ___ and ___
luminal
* α-glycosidase, glucose
* glucose and fructose
* glucose and galactose
T or F: only monosaccharides are absorbed in the body
True
Bacterial contribution
- Bacterial enzymes break down carbs that we cannot by metabolizing them ___.
- Results on production of ___ fatty acids, lactate, ___, ___, and ___.
- May cause ___ and abdominal discomfort.
- anaerobically
- short chain, H2, CH4, CO2
- flatulence
The glycemic index measures how ___ individual foods with raise ___ level.
* ratio of the AUC of the ___ response curve to that of ___
quickly, blood glucose
* blood glucose response, glucose
Dietary Fibers
Cellulose and Hemicellulose
* found in ___ cereals, ___, and ___ wheat
* increase ___ bulk and decreases ___ transit time
* insoluble
- unrefined, brand , whole
- stool, intestinal
Dietary Fibers
Lignin
* found in the ___ parts of vegetables
* binds ___ and ___
* insoluble
- woody
- cholesterol and carcinogens
Dietray Fibers
Pectin
* found in ___
* decreases rate of ___ uptake and decreaces serum ___
* soluble
- fruits
- sugar, cholesterol
Lipids in Diet
- efficient source of energy ___ kcal/g
- carrier for ___ vitamins
- ___ is greater than 90% of dietary fat
- ___, cholesterol, ___ esters, and fatty acids are less that 10% dietary fat.
- 9 kcal/g
- fat soluble
- triacylglycerol
- phospholipids, cholesterol
Essential fatty acids
ω-3 fatty acids
* __ acid (18:3) in ___ oils
* ___ acid (20:5) and ___ acid (22:6) in ___ oils
- α-linolenic, vegetable
- Eicosapentaenoic (EPA), docosahexaenoic (DHA), fish
Essential fatty acids
ω-6 fatty acids
* ___ acid (18:2) in ___ oil
* ___ acid (20:4) in ___ and ___
- linoleic, corn
- arachidonic, meat and fish
Essential fatty acids
- used to synthesize ___
- deficiency is rare in US
- ratio of ω-3 to ω-6 fatty acids in the diet is important in regulating blood ___, blood ___, and ___ functions
- eicosanoids
- blood pressure, blood clotting, immune
Trans fatty acids
- unsaturated fatty acids found in nature have ___ double bonds
- hydrogenation converts ___ fatty acids to ____ fatty acids and produces ___ fatty acids as byproducts
- ___ fatty acids have a higher melting point that ___ configuration
- trans fats raise blood ___ levels and increase the risk of ___ disease.
- cis
- unsaturated to saturated, trans
- trans, cis
- cholesterol, heart
Digestion of Lipids
- fat needs to be ___ for digestion
- this is done by ___ acids
- gastric and pancreatic ___ hydrolyze triacylglycerol to ___ and monoacylglyceryol
- fatty acids act as ___
- esterase hydrolyzes monoacylglycerol and ___ ester
lipid phase made into small droplets
- solubilized
- bile
- lipases, fatty acids
- surfactants
- cholesterol
Utilization of lipids
- ___ delivers lipid to peripheral tissues directly
- ___ uses fat as an energy source
- ___ does not used fat
- when starved, liver converts fatty acid to ___ which are the used by ___ and ___
- chylomicron
- muscle
- brain
- ketone bodies, brain, muscle
Proteins in Diet
Excess protein is a source of energy
* eventually converted to triacylglycerol in ___ tissue
* makes up ___ body weight
- adipose
- 20%
Nitrogen Balance
negative nitrogen balance - ___ dietary intake of protein, trauma or illness
positive nitrogen balance - growing children, ___ women, or adults recovering from illness
- inadequate
- pregnant
T or F: essential amino acids are synthesized by the body in sufficient amounts
False; they are the ones that can’t be synthesized or cannot be made sufficiently
arginine, methionine, and phenylalanine
what are conditionally essential amino acids
amino acids that cannot be made if an essential amino acid is not ingested
if phenylalanine is not ingested enough, tyrosine cannot be made
Digestion of Proteins
Gastric digestion
* low pH of ___ denatures proteins
* ___ are stable and active at acidic pH; espartic protease
- 2
- pepsins
Digestion of Proteins
Intestinal digestion - ___ at the luminal surface
* brush border at the luminal surface of ___ cells
* rich in ___
* produce free amino acids and di and tri___
peptidases
* epithelial
* peptidases
* peptides
Digestion of Proteins.
Intestinal Digestion - ___ peptidases
* amino acid and peptide ___ systems
* intracellular ___ of di and tripeptides
* practically only ___ amino acids are realeased to blood.
intracellular
* transport
* hydrolysis
* free
Celiac Disease
- ___ intolerance
- ___ disorder in genetically predisposed individuals
- caused by ___ to gluten
- major proteins contained in ___, ___ , and ___
- lining of ___ is inflamed and damaged causing ___ , ___ , and ___
- gluten
- autoimmune
- exposure
- wheat, rye, and barley
- small intestine, diarrhea, weight loss, and malnutrition
Energy Reserves
- excess energy is stored mostly as fat in ___ tissue
- glycogen in the liver to maintain ___ levels
- glycogen in muscle is used for ___
- protein is not a ___ energy reserve
- adipose
- blood glucose
- exercise
- preferred
Well-fed state
- ___ release
- glycolysis and ___ synthesis
- catabolism of ___ acids
- ___ acid synthesis
- no ____ = no ___ cyclle
- insulin
- glycogen
- amino
- fatty
- gluconeogenesis, Cori
Early Fasting State
- ___ release
- ____ breakdown
- gluconeogenesis: ___ cycle and ___ cycle
- no ____ of amino acids
- glucagon
- glycogen
- Cori, Alanine
- catabolism
Fasting State
- ___ release
- gluconeogenesis
- protein is used as a major carbon and ___ source (2 amino acids)
- ___ in adipose tissue
- fatty acid ___
- ketogenesis
- reduced ___ hormones
- daily basal energy requirement drops by ___%
- glucagon
- nitrogen (alanine, glutamine)
- lipolysis
- oxidation
- thyroid
- 25%
Caloric Homeostasis
- if [glucose] < ___ nM (27 mg/dL), coma and death with follow
- hyperglycemia leads to ___ , ___ coma, and complications of ___
- 1.5 nM
- dehydration, hyperglycemic, diabetes
Energy for Brain
- brain uses more than ___% of total energy
- ___ g of glucose/day is preferred
- uses ___% of total oxygen
- membrane potential uses ___ ATPase
- brain does not use ___ or ___ storage
- use ketone bodies during starvation made from ___ in the liver
- 20%
- 100-120g
- 15-20%
- Na+/K+
- fat, glycogen
- acetyl-CoA
Protein-energy malnutrition
Marasmus: inadequate intake of both ___ and ___
* thin, wasted appearance
protein and energy
Protein-energy malnutrition
Kwashiorkor: inadequate intake of ___ with adequate ___ intake
* mainly in children ___ years of age
* deceptice plump appearance due to ___
protein, energy
* 1-3
* edema
