Energy systems Flashcards
APPLIED ANATOMY AND PHYSIOLOGY
what is kinetic energy?
any energy that causes movement
where is electrical energy stored and when released?
stored and released by charged particles, the human body uses it to pass impulses through nervous system
where is chemical chemical energy found and when released?
found in foods we eat and released during chemical reactions
where is potential energy stored?
within an object due to its position (e.g. energy in muscle tissue)
what does ATP stand for?
adenosine triphosphate
1x adenosine and 3x phosphate molecules
what is aerobic respiration?
the usual process for releasing energy for your muscles occurring WITH oxygen
what is the equation for aerobic respiration?
glucose + oxygen = energy + c02 + water
what is anaerobic respiration?
when the muscles have to work at a very intense level occurring WITHOUT oxygen
what is the equation for anaerobic respiration?
glucose = energy + lactic acid
when is aerobic and anaerobic respiration required?
aerobic = low intensity exercise, minutes or hours
anaerobic = high intensity exercise, short period of time
what are the anaerobic energy systems?
- ATP-PC
- Glycolytic system (lactic acid)
what are the aerobic energy systems?
- glycolysis
- krebs cycle
- electron transport chain
(in that order)
how does ATP-PC release energy?
- The ATP-PC system is an anaerobic energy system (does not require oxygen).
- It uses phosphocreatine (PC) stored in the muscles to regenerate ATP.
- When high-intensity activity begins, ATP is broken down into ADP + Pi, releasing energy for muscular contractions:
→ ATP → ADP + Pi + energy - PC is then broken down by the enzyme creatine kinase to release a phosphate:
→ PC → P + C + energy - The released phosphate is used to resynthesize ATP from ADP:
→ ADP + P → ATP - This process is very rapid, allowing for immediate energy supply.
- However, PC stores are limited, so the system only lasts 8–10 seconds.
- It’s predominantly used in explosive, high-intensity activities like sprinting, jumping, or weightlifting.
where does ATP-PC occur?
sarcoplasm (cytoplasm of muscle cell)
pros and cons of the ATP-PC system
pros:
- no by products
- quick and impulsive
cons:
- limited phosphocreatine stores
- only at high intensity for short time
- 3 minutes to recover
sport examples of when ATP-PC system is used
- lacrosse shot
- golf swing
- pass in netball
when is the glycolytic system used?
to produce energy once PC stores have been used up, anaerobically
how does the glycolytic system release energy?
- when ADP and Pi levels rise, enzyme phosphofructokinase (PFK) is released
- PFK catalyses the breakdown of glucose in the blood
[ if glucose levels are low, enzyme phosphroylase (GPP) breakes down glycogen to retain glucose concentration back in blood ] - then system is converted to pyruvic acid
1. [ if exercise is without oxygen, pyruvic acid is converted to lactic acid by enzyme lactate dehydrogenase as energy isn’t able to be continually extracted ]
2. [ if exercise is with oxygen pyruvic acid converts to Acetyl CoA to enter aerobic energy system ]
how does the build up of lactic acid affect ATP resynthesis?
- build up of lactic acid inhibits enzyme activity therefore slowing rate of ATP resynthesis
- leads to fatigue and onset blood lactate accumulation (OBLA)
pros and cons of glycolytic system
pros:
- 1:2 yield = 2 ATP back
- goes for longer period of time (compared to ATP-PC)
cons:
- produces by products (NADH and lactic acid)
- only lasts 3 minutes with 10 minute recovery
how does the aerobic systems release energy? (usually a 6 marker)
- glycolysis occurs in sarcoplasm
- glucose is broken down into pyruvic acid producing 2 ATP
- pyruvic acid is converted to Acetyl CoA at presence of oxygen
- krebs cycle takes place in mitochondria
- acetyl coa enters krebs cycle which produces, 2 ATP, Co2 when exhaled, by products FADH+NADH and hydrogen ions
- hydrogen ions are carried around by NAD and FAD
- electron transport chain also happens in the mitochondria
- hydrogen ions are transported on the electron transport chain in the inner membrane of mitochondria
- the electrons go through a series of reactions to produce 34 ATP molecules, energy and water as a by product
- overall producing 38 ATP
what happens when glucose stores have run out and the body still needs energy?
- begins breaking down fat stores (secondary energy source)
- fat is broken down into fatty acids
- with beta oxidation the fatty acids are converted to Acetyl CoA to resynthesises ATP for energy
pros and cons of aerobic energy system
pros:
- 1:38 yield
- with oxygen
cons:
- produces by products (Co2 + water)
- longer recovery
- low intensity exercise only
when is each energy system and provide examples:
ATP-PC: provides energy during maximal intensity
- 100m sprinter
- power lifter
GLYCOLITIC: provides energy during high intensity for intermediate period of time
- 200m sprinter
- team sports
AEROBIC: provides energy during low intensity exercise for extended periods of time
- marathon runners
- triathlon runners
