1.1c Energy systems Flashcards
Coupled reaction?
Where the products of one reaction are used in another
ATP-PC system?
The body’s ‘turbo system’ - produces energy quickly for maximal bursts, but also depletes quickly.
Aerobic system?
Involves the complete breakdown of glucose and can sustain long-term energy production at low-moderate intensity.
Reversible reaction
A reaction that can take place in either direction.
Glycolytic system?
The partial breakdown of glucose during high intensity effort, resulting in the production of lactic acid.
ATP?
energy currency
A high energy compound which is the only immediate available sourse of energy for muscular contraction.
Exothermic reaction?
A chemical recation that releases energy.
Endothermic reaction?
A chemical recation that absorbs energy
Energy?
The capacity to perform work and can exist in chemical, potential and kinetic forms.
Where do we get energy?
- Food contains chemical energy. This is digested and stored as potential energy.
- Fuels can be metabolised to create kinetic energy.
ATP - adenosine triphosphate?
- universal currency of the human body
- stored inside cytoplasm of the muscle cell
How much ATP is readily available?
2 seconds worth
What needs to happen to ATP to continue exercising?
ATP needs to be resynthesised by PC
what is the controlling enzyme of PC?
creatine kinase
what is the fuel for PC?
phosphocreatine
what is the controlling enzyme of ATP?
ATPase
what part of the ATP/PC system is exothermic
when a high energy bond is broken and energy is released
eg pc = p + c + energy
eg atp = adp + p + energy
what part of the ATP/PC system is endothermic
when energy is used to resynthesise
eg adp + p + energy = atp
what is the energy yield of the atp/pc system
1:1
advantages of the atp/pc system
- PC readily available on site
-anaerobic so no wait for oxygen
-simple structured and reactions
-not fatiguing by-products
disadvantages of atp/pc system
-limited stores of pc run out quickly
-once exhausted, can’t be used again until adequate recovery
-inefficient in comparison to other systems
fuel of glycolytic system
glycogen/glucose
site of glycolytic system
cytoplasm of the muscle cell
process of the glycolytic system
-glycogen reacts with glycogen phosphorylase to produce
glucose
-glucose reacts with phosphofructokinase to produce 2x energy and pyruvic acid
-pyruvic acid reacts with lactate dehydrogenase to produce lactic acid
by product of glycolytic system
lactic acid - fatigue
LA accumulates and causes OBLA
inc acidity in muscle cells inhibits enzyme activity
energy yield of glycolytic system
1:2
strengths of glycolytic system
-no O2 require means quick access
-large fueld stores to resynthesis more than atp/pc
-relatively few chemical reactions
-la can be recycled back into glycogen
weakness of glycolytic system
-lactic acid causes muscle fatigue and can only be used for max 3 mins
-relatively low atp yield
-long recovery to remove la
what are the four stages of the aerobic system
-aerobic glycolysis
-link reaction
-krebs cycle
-electron transport chain
process of aerobic glycolysis
-glycogen + gpp = glucose
-glucose + pfk = pyruvic acid + 2x energy
location of aerobic glycolysis
cytoplasm of muscle cell
process of the link reaction
-pyruvic acid + coenzyme A = acetyl coa
-acetyl coa + oxaloacetic acid = citric acid
location of the link process
cytoplasm of muscle cell
process of Kreb’s cycle
-citric acid oxidised by o2 = 2x energy
-co2 is removed
-hydrogen leaves
location of Kreb’s cycle
matrix of mitochondria of muscle cell
process of electron transport chain
-H atoms carried by hydrogen carriers nad and fad
-H split into ion H+ and electron H-
-H+ + o2 = h2o and removed
-pairs of H- carried and form nadh2 and fadh2
-release 30 + 4 x energy
location of electron transport chain
cristae of mitochondria in muscle cell
energy yield of aerobic system
1:38
strengths of glycolytic system
-large fuel stored to last hours of activity
-large amount of ATP resynthesised from 1 mol of glucose
-no fatiguing byproducts
weakness of aerobic system
-fatty acids require 15% more oxygen to metabolise and be used
-delay of o2 delivery and series of reaction is slow
-limited to sub-max work
duration and intensity of atp/pc system
short duration (max 10s)
max intensity
eg 100m sprint in athletics
duration and intensity of glycolytic system
medium duration (max 3 mins)
high intensity
eg 800m in athletics
duration and intensity of aerobic system
long duration (>3 mins)
low intensity
eg marathon run
what is the energy continuum
the relative contribution of each energy system to overall energy production
energy continuum and intermittent exercise
activity where intensity alternates
eg interval training (w:r ratios) or gameplay with breaks or varying intensities
-more energy demanding than continuous work
-game players physiologically develop all 3 energy systems
energy continuum and threshold
the point at which an athletes predominant energy production moves from one energy system to another
how does fitness level effect energy continuum
-high Vo2 max max and aerobic capacity means efficient utilisation of great vol of o2
-increased intensity they can perform before obla and increases buffering capacity
-oxygen arrives quicker and minimise time in glycolysis
-ffa require 15% more oxygen to break down - trained can do this and save glucose
