NS prelim 1 Flashcards
how does the human body store energy?
chemical energy extracted from food
simple form of CHO
Glucose
stored form of CHO
glycogen
primary store sight of CHO
muscle > liver
simple forms of lipids and fats
free fatty acids
stored forms of lipids and fats
triglycerides
primary store site of lipids and fats
adipose tissue > muscle > serum
simple forms of proteins
amino acids
stored forms of proteins
not really
primary store site of proteins
muscle
exception about protein energy storage
amino acids cannot be stored for later use. however, under very extreme metabolic conditions such as prolonged starvation, muscle will be broken down and its main constituent amino acids will be used to produce energy
energy intake balance components
CHO, proteins, lipids and fats, alcohol
3 examples of energy expenditure in the body
basal metabolism, thermogenesis, physical activity
basal (resting) metabolic rate
energy needed to perform normal body functions
thermogenesis
the energy cost of food processing
examples of processes for basal metabolic rate
respiration, circulation, digestion
examples of processes for thermogenesis
ingestion, digestion, absorption, transport, and storage. including peristalsis and segmentation.
physical activity energy expenditure
body movement determining activity-induced
how to measure energy in units
expressed in a 1000-calorie metric unit known as kcal
1 kcal to joules
4184 joules
1 kcal to cal
1000 cal
1 kcal to dietary cal
1 dietary cal
scientific terms for calories
1 calorie is the unit of E required to increase the temperature of 1 g of water by 1 degree Celsius
methods of measuring energy
assessing O2 consumption, CO2 production, and heat released from metabolized nutrients
how to calculate energy theoretically
calories can be calculated by burning food and measuring the heat produced
calorimetry
the change in E of a system by measuring heat exchange
calorimeter
an instrument to measure the transfer of heat
bomb calorimeter
used to determine the E content of nutrients
bomb calorimeter energy value for carbohydrates
4.3 kcal
bomb calorimeter energy value for lipids
9.45 kcal
bomb calorimeter energy value for protein
5.65 kcal
bomb calorimeter energy value for alcohol
7.0 kcal
energy digestion value for carbohydrates
4 kcal
energy digestion value for lipids
9 kcal
energy digestion value for protein
4 kcal
energy digestion value for alcohol
7 kcal
calorimetry rooms
are big enough to contain a person and can be used as a direct form to measure the body’s heat production. this is not a very practical or accurate method, especially while exercising.
indirect calorimetry
measures respiratory gas exchange
example of direct calorimetry
calorimetry rooms
VO2
volume of O2 consumed per min.
VO2 equation
volume of O2 inhaled minus volume of O2 exhaled
VCO2
volume of CO2 produced per minute
VCO2 equation
volume of CO2 exhaled minus Volume of O2 inhaled
how to estimate energy expenditure using indirect calorimetry
the ratio of O2 consumed compared to CO2 produced can be used
Respiratory Exchange Ratio (RER)
measurement of how many CHO or fats we are using for energy
RER equation
RER = VCO2 / VO2 = CO2 made / O2 used
oxidation of palmitic acid in RER
0.71 (only fats)
oxidation of glucose in RER
1.00 (only carbs)
Cellular currency
ATP
Catabolism
the process of when the body needs energy, it breaks down compounds
3 basic units of ATP
a sugar called ribose, a base called adenine, and 3 phosphate groups
where is the energy in ATP stored
in chemical bonds between the phosphate groups
3 energy compounds that are
constantly interconverted
AMP, ADP, ATP
hydrolysis
ATP breakdown
how much energy is released from hydrolysis
7.3 cal/mol
how is energy released with ATP?
when a high-energy phosphate bond in ATP is broken. The loss of 1 phosphate from ATP results in the formation of ADP
product of hydrolysis
ADP + inorganic P or AMP + 2P
substrate phosphorylation
the addition of a phosphate group directly to ADP
where does the ATP energy come from
the breakdown of energy-yielding nutrients
anabolic reactions
chemical reactions that require energy
energy for anabolic reactions
the body uses ATP to transfer energy from catabolic reactions to power anabolic reactions
how to make a nonspontaneous reaction into a spontaneous one
the E released from hydrolyzing ATP is transferred to make unfavorable reactions favorable
metabolic pathways
catabolic reactions are coupled with anabolic reactions in a complex scheme to be able to do work
3 examples of metabolic pathways in the body
moving muscles, synthesizing compounds, or transporting nutrients
Substrate Product Metabolic Pathway
what types of energy do cells interconvert with high efficiency
chemical, electrochemical, mechanical, and osmotic energy
electron transport chain (ETC)
catabolism of the three energy-yielding nutrients starts down a different path, but they have the same destination of the ETC
glycolytic energy system substrate
carbohydrates (glucose and glycogen)
glycolysis
the breakdown of carbohydrates to resynthesize ATP. involves a series of 10 reactions that occur in the cytoplasm of cells (sarcoplasm of muscle cells)
how does glycolysis produce ATP
energy pathway uses glucose from the blood and liver or glycogen stored in the liver and muscles
glycogenolysis
breakdown of glycogen from liver or muscle into glucose within the blood or liver to synthesize ATP
glycogenesis and location
when glucose from the blood or liver is made into the glycogen polymer in the liver or muscle
pyruvate
end product of glycolysis which may proceed in one of two directions
lactic acid
one pathway for pyruvate through the Cori cycle
Acetyl CoA
one pathway for pyruvate through the TCA cycle
anaerobic glycolysis alternative terms
anaerobic respiration, fast glycolysis, lactic acid fermentation
anaerobic glycolysis
takes place when the body needs energy quickly such as intense exercise. ATP resynthesis occurs at a faster rate but is limited in duration.
aerobic glycolysis alternative terms
aerobic respiration or slow glycolysis
aerobic glycolysis
takes place in the mitochondria. when pyruvate is shuttled into the mitochondria the ATP resynthesis rate is slower, but it can occur for a longer period.
glycolysis general process summarized
intake of complex carbs to pyruvate to oxygen determining processes
macronutrient fact: Acetyl CoA
the METABOLISM of all energy-yielding nutrients starts at different points but all arrive at acetyl CoA
two directions Acetyl CoA can proceed
oxidative phosphorylation to generate ATP or lipogenesis for the synthesis of fats