Human Energy Transfer Flashcards
Energy
Capacity to do work
Metabolism
Total of all energy transformation that occur in the body
Energy transfer
All of the metabolic processes that are involved in the production and utilization of adenosine triphosphate
ATP
Stored chemical energy that links the energy yielding and energy requiring function within all cells
Currency of cells
Structure of ATP
Adenosine linked to three phosphates
Where does ADP come from?
ATP + water and catalyzed by adenosine triphosphatase
Hydrogen is also released - no change of pH due to breakdown and rebuild
How is ATP energy released?
ATP HYDROLYSIS liberates energy to do biological work
Bioenergetics
Flow and exchange of energy within a living system
1st law of thermodynamics
Law of conservation of energy - law that human body is subjected to
Energy can neither by created or destroyed
Catabolic
Energy is produced from the breakdown of foodstuffs
ADP AND PI SND ENERGY gives ATP (endergonic)
Anabolic
Energy is used to build tissues
ATP into ADP AND PI AND ENERGY (exergonic)
Coupled reactions
Linking of an energy yielding and energy requiring reaction.
Sliding filament theory and 2ATP uses
Thick over thin
Neurotransmitters trigger AP which moves along the cell membrane, then ATP and Ca bind to troponin and a shift as tropomyosin occurs
ATP needed for ca to go back to SR through ATPase pumps
Three types biological work that use energy
Mechanical
chemical
transport
Is all the energy from food converted into ATP and mechanical work?
No some is released as heat according to the second law of thermodynamics
Food is converted into
Mechanical energy and heat
Total energy expenditure is proportional to
Work done and heat produced - 2nd law of thermodynamics
O2 + macronutrients
= ATP And CO 2 and h2o
Mechanical work from ATP is measured by
Ergo meter
Heat from ATP is measured by
Direct/indirect calorimeter - o2 and co2 that you breath out
What do you need to measure to figure out how much ATP you used?
Mechanical work and heat
How doe muscles use ATP
Binds to myosin heavy chain ATPase which is structurally bond to the myosin head
Cross ridge, power stroke, one to detach the Cross bridge then cocking
ATP in skeletal muscle at rest
6mmol/kg, 80-100g of ATP
Good because its heavy
How much body weight do we resynthesize in ATP per day
With normal daily PA, 75 of our body weight
How long will stored ATP last us at max activity
3s
How much ATP is used to run a marathon?
80kg
What stimulates ATP synthesis?
Small changes in the concentrations of ATP, ADP and Pi
When do ATP levels in skeletal muscle decrease?
Extreme exercise, and it never drops below 40% except for death
Response to a minimal ATP decrease in cells
Rapid change in concentration because there only a small amount of ATP Within the cell
5 energy sources for ATP generation
Creating phosphate Mayo kinase reaction Glucose/glycogen Fat Protein
All operate at diff rates with PC being the phosphate, as it contains a phosphate group it can immediately re phosphate ADP
Short exercises and ATP resynthesis
Up to 6 seconds - stored ATP
up to 10 - PC and ADP (myokinase - make two ADP Into ATP and AMP)
30-end - glycogen to glucose to ATP with metabolic by products as lactate and hydrogen
Prolonged duration exercise and ATP resynthesis
Generated by breakdown of macronutrients by aerobic pathway, using oxygen from myoglobin or delivered by hemoglobin, oxygen deficit removed when activity ends
Three biomechanical pathways/systems of ATP resynthesis
- Phosphogen - ATP-PC alactic - instantaneous - C&ATP
- Anaerobic respiration -fast glycolysis, lactic - glycolysis or glyconeogenolysis (predominates) - immediately - ATP & Pyruvic acid that turns into lactic acid
- Aerobic respiration - Glycolysis, kerbs cycle, ETC/oxidative phosphylation - ongoing but lags to meet increased needs. ATP at 3 places - glycolysis, kerbs and ETC
Cellular respiration
Process by which cells transfer energy from food to ATP in stepwise series of actions - relies heavily upon use of oxygen
Substrate level phosphylation
Direct transfer of Pi from phosphorylated immediate or substrate to ADP without any oxidation occurring - glycolysis and kerbs
Oxidative phosphorylation
The process by which NADHH and FADH2 are oxidized in the electron transport system and energy is usedtovsynthesize ATP from ADP and Pi
Endocrine system in ATP resynthesis
Mobilize stored fuel of glucose and FA for regeneration of energy (ATP) to support muscle contraction
e and NE (catecholamines) and growth hormone and cortisol
Glucagon
Acts on liver to release sugar into blood stream
Gluconeogenesis
Breaking protein down to make glucose
Relative contribution of anaerobic versus aerobic energy
Energy continuum
Short and intense is anaerobic
3s - ATP then at 10s glycolysis then at around 90 aerobic dominates
Why is the system approach beneficial? 2
Permits classification if demands of exercise, sport and PA
design training programs
Timeline of energy systems
ATP - PC Predominate in activities of 10 sec
glycolytic - lactic - 1-2 mins
Aerobic - activities greater than 2 mins
