Metabolism Flashcards
Nutrient
molecule obtained from food that body requires for its metabolic processes
5 main categories of nutrients include
fuel molecules carbohydrates, proteins, and lipids
Vitamin and minerals
Structural molecules such as cholesterol
Macronutrients
carbohydrates, proteins, and lipids; required in relatively large amounts, thus make up bulk of diet
Micronutrients
vitamins and minerals because they have much lower requirements in diet
Essential nutrients
molecules that body is incapable of producing and must obtain from dietary sources
Carbohydrates
in diet consist of monosaccharides, disaccharides
Fiber
group of polysaccharides that are not fully digestible by humans
Found in whole grains, fruit skins, and bran; passes through digestive tract virtually unaltered
insoluble
Partially digested by bacteria in colon into compounds that can be absorbed into bloodstream
soluble
In diet include triglycerides, cholesterol, and certain vitamins
lipids
hydrocarbon chains without any double bounds; include mostly animal-derived products
saturated fatty acids
contain one double bond (monounsaturated) or more double bonds (polyunsaturated); found commonly in plant-derived products
unsaturated fatty acids
Those fats that body is unable to synthesize and must be obtained from diet.
essential fatty acids
______ and 20 amino acids used in their construction are important molecular fuels, structural molecules, and enzymes.
proteins
11 amino acids that can be synthesized from carbon skeletons
nonessential amino acids
nine amino acids, which cannot be synthesized and must be obtained from dietary sources
essential amino acids
Functions: oxidized for energy, used in production of other substances, incorporated into multiple structural molecules
carbohydrates
Functions: oxidized for fuel, used to form structural molecules, glycerol used for gluconeogenesis
lipids
Functions: used to form structural molecules, used to manufacture enzymes, antibodies and hormones, oxidized for fuel, used for gluconeogenesis
proteins
include vitamins and minerals; not used as fuel; play critical roles in nearly all of body’s physiological processes
micronutrients
13 organic compounds to date; required for body’s functions
vitamins (vital amines)
hydrophobic compounds structurally similar to cholesterol; include vitamin A,D, E, K
fat-soluble vitamins
hydrophilic compounds featuring polar covalent bonds; include vitamin C and B
water-soluble vitamins
any element other than carbon, hydrogen, oxygen and nitrogen required by living organisms; not used as fuels but are important components in many physiological processes
minerals
seven major minerals- ions that are required in moderate amounts for optimal health:
calcium, chloride, magnesium, phosphorus, potassium, sodium, and sulfur
______ is packaged along with other lipids and proteins into structures called _____
cholesterol, lipoproteins
Provide ________ for cholesterol and other lipids in bloodstream; types of lipoproteins differ in ratios of lipid to protein.
transportation
Two types of lipoproteins:
very low-density lipoproteins (VLDLs)
lipoprotein lipase
synthesized in liver and released into bloodstream or small intestine
high-destiny lipoproteins (HDLs)
___ is considered “good” cholesterol because it carries cholesterol back to liver where it is ____ from body as component of bile.
HDL, excreted
Transport primarily triglycerides from liver to adipose tissue for storage and to muscle tissue for immediate use as fuel
very low-density lipoproteins (VLDLs)
Considered “bad” cholesterol because they carry cholesterol to peripheral cells; can contribute disease.
VLDL and LDL
amount of matter in body
body mass
(more commonly used) refers to force exerted on body mass by gravity
body weight
equation that accounts for height; provides reference range that helps to determine relative body mass
body mass index (BMI)
difference between energy intake and energy expenditure; determines rate individual gains or loses body mass
energy balance or nitrogen balance
meets an individual’s needs in terms of micronutrients, macronutrients, essential amino acids and other molecules such as cholesterol
healthy diet
resource provided by USDA in 2011; depicts proportions of types of foods that should make up nutritious meal
myplate
individuals who have body mass index of greater than 30.0 are considered ____
obese
measure of heat; one calorie is the amount of heat required to raise the temperature of one gram of water by one degree Celsius
Calorie (C)
actual unit of calorie used to measure human diet; one kilocalorie is the amount of heat required to raise the temperature of one kilogram of water by one degree Celsius
Kilocalorie
Sum of body’s chemical reactions; series enzyme-catalyzed reactions
metabolism
harnessing energy in chemical bonds of molecules obtained from diet (____) ; may be used to make _____
nutrients, ATP
harnessing energy in chemical bonds of molecules obtained from diet nutrients ; may be used to make ATP, is apart of what?
metabolic pathways
converting one type of molecule into another for cell’s synthesis reactions
metabolic pathways
synthesizing macromolecules such as proteins, polysaccharides, nucleic acids, and lipids
metabolic pathways
breaking down macromolecules into monomers or other small molecules
metabolic pathways
series of reactions in which one substance is broken down into smaller parts
catabolism
process as whole releases energy that cell can harness to drive other processes
catabolism
Body catabolizes three types of nutrient monomers to generate ATP
glucose, fatty acids mainly triglycerides, amino acids
breakdown of dietary and stored carbohydrates, carried out by every cell in body, is preferred fuel for many cells including those of brain and liver
glucose
broken down into free fatty acids and glycerol, can proceed into separate catabolic pathways or can be used by cell for other purposes
fatty acids - mainly triglycerides
liberated by catabolic pathways that breakdown proteins, amino acids can proceed into separate catabolic pathways or can be used by cell for other purposes
amino acids
series of reactions in which smaller molecules are combined to make larger molecule
anabolism
Anabolism: Cells use smaller molecules to build larger macromolecules such as:
proteins, nucleic acid, lipids, carbohydrates
chemical reactions are usually paired such that energy released from exergonic reaction (usually _______ process) feed liberated energy into endergonic reaction (usually_____ process)
catabolic, anabolic
Energy present ____ reaction (in reactants) must equal energy present ____ reaction (in products or as liberated energy.
before, after
release energy leaving products with less energy than original reactants possessed
exergonic reactions
most catabolic reactions are
exergonic
require input proceed, products possess more energy than reactants, energy must be added to reactant side of equation to satisfy law of conservation of energy
endergonic
most anabolic reactions are
endergonic
energy is release from _____ _____ reactions
exergonic catabolic
used to fuel _____ _____ reaction to ATP synthesis
endergonic anabolic
ATP is broken down in ______ reaction
exergonic catabolic
energy from ATP breakdown fuels another ____ ____ reaction in cell
endergonic anabolic
ATP is inherently ______ molecule
unstable
bond between second and third phosphate group has been misnamed “____ _____” ; possesses no more energy than other bonds.
high-energy
cells harness ATP energy by removing third phosphate group in _____ reaction
hydrolysis
bond between second and third phosphate groups is broken with _____ molecule, releasing free phosphate and ADP.
water
ATP hydrolysis is ____ exergonic but cell is only able to harness about 40% of released energy to perform work
highly
