Transcript Energy + ADP + P = ATP

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Define ‘energy’, ‘work’, and ‘power’.
Identify examples of potential, chemical and kinetic
energy within the body.
The role of ATP within the body and explain how energy
is made available for muscular contraction.
Describe the three energy systems for ATP re-sythesis
Identify the thresholds of each of these systems.
Explain the term ‘OBLA’
Explain the factors that determine how these systems
combine to provide energy for different sporting
activities.
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Energy is the ability to perform work.
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Energy is measured in Joules (J)
It is also measured in calories
 1 calorie = 4.18 joules
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total intake of food sufficient to supply
enough energy to :
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keep cells alive
keep systems working
meet demands of life
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Neutral energy balance:
Energy input = Energy output
Negative Energy balance:
Energy output > Energy input
Balanced diet and regular aerobic exercise is the most
effective means of weight control.
Basal Metabolic Rate = the rate at which energy is used
by basic bodily functions (@ rest or sleeping)
Total Metabolic Rate = the rate at which energy is used
by all bodily functions including exercise
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FOOD
KILOJOULES
PER GRAM
KILOCALORIES
PER GRAM
FAT
37
9
ALCOHOL
29
7
PROTEIN
17
4
CARBOHYDRATES
16
4
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Calories
in:
a 100g bar of Cadbury's Dairy Milk: 530kcal
a pack of Maltesers: 183kcal
a Mars Bars (65g): 294kcal
A 30g bowl of Corn Flakes: 112 cal
Check out
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www.whatsinsideguide.com
www.brianmac.co.uk/energyexp.htm
www.weightlossresources.co.uk/calories/c
alorie_counter
www.bmi-calculator.net
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WORK = force x distance moved
Force = a push or pull that alters, or tends to alter, the state of
motion of a body. Measured in Newtons.
measured in joules (J)
WORK = force x distance moved
 A rugby players spear tackles a
stationary 95kg opponent. He drives
him back 2 metres? How much work
did he do before he was sent off and
banned for 3 months?
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is the rate at which we can work or
work/time
 the energy used per second
 POWER = work/time
 Considered a combination of strength
and speed
 unit = watt (W)
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ATP is adenosine triphosphate.
This compound is the only immediately
usable form of energy stored in our
bodies.
We have other energy rich compounds
such as phosphocreatine and glycogen.
CHEMICAL ENERGY
 is energy that is produced by a complex series of
chemical reactions
 Stored as …..
 which can then be made available as :
KINETIC ENERGY
 is energy due to movement
 which results from muscular contractions
POTENTIAL ENERGY
 is stored energy waiting to happen.
 eg. ATP does nothing until P group is released with the
help of ATPase.
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However, ATP is the only one that can be
utilised by the muscles to create movement.
ATP is stored within the muscle cell
Total mass of 85g within the body
Enough to last for about 2 seconds of
exercise.
To maintain exercise, ATP has to be resynthesised from adenosine diphosphate
(ADP) and a phophate group (‘P’ of ‘Pi’)
High-energy
bond
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Adenosine
P
P
Adenosine
P
P
P
The energy is stored in the
bond between the last two
phosphate groups.
ATPase
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When this bond is broken by
the action of the enzyme
ATPase, energy is released
that can be used by the
muscle cell to contract.
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ATP re-synthesis is achieved by 3 energy
systems:
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The Phosphocreatine system
Lactic acid system
Aerobic system
The amount of ATP re-synthesis is done by each
system will depend purely on the intensity of the
exercise.
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Two systems can be working at the same time.
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This system uses another high-energy compound known as
phosphocreatine to provide energy to combine ADP and P.
PC = P + C + energy
Energy + ADP + P = ATP
Advantages
(exothermic)
(endothermic)
Disadvantages
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Provides ATP re-sythesis very quickly because
the PC is stored in the sarcoplasm of the
muscle cell and there are very few steps in the
reaction
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There is only a small amount of PC stored in
the muscle cells.
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O2 is not required, therefore there is no delay
to wait for oxygen to be supplied from the
lungs
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Only one mole of ATP is re-synthesised from
one mole of PC
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It can provide energy for very high-intensity
exercise.
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It will only provide energy for a maximum of
ten seconds
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Recovery times for this system are very quick,
as PC will re-synthesise quite quickly.
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There are no harmful by products that will
cause fatigue.
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Another anaerobic system
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takes place in the sarcoplasm
The fuel used is CHO.
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Stored in the muscles and liver as glycogen.
CHO is converted to glucose by the enzyme glycogen
phosphorylase and undergoes a series of reactions
known as anaerobic glycolysis.
This is started by the enzyme phosphofructokinase (PFK)
until eventually it is converted into pyruvic acid.
During this process 2 moles of ATP are re-synthesised.
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Due to the lack of oxygen, the pyruvic acid is converted to lactic
acid by the enzyme lactodehydrogenase.
Glucose
PFK
Lactic acid
2 ATP
Pyruvic acid
LDH
Advantages
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There is a relatively large supply of
glycogen stored in our bodies and so ths
system can supply more ATP than the
PC system
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ATP can be provided quickly for highintensity activities that last from
anywhere from 15-180 secs.
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O2 is not required, therefore there is no
delay to wait for oxygen to be supplied
from the lungs
Disadvantages
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The bi-product, lactic acid, reduces the
pH of the muscle cell, making it more
acidic; this prevents the enzymes from
functioning properly, causing fatigue.
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Requires Oxygen as a fuel alongside glycogen or fat to resynthesise ATP
First part of the system is identical to the lactic acid system.
However the pyruvic acid is not converted into lactic acid. Instead
it is taken by the co-enzyme acetyl CoA into the Kreb’s Cycle.
Here a series of chemical reactions occurs, further breaking down
the CHO compound.
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This takes place in the matrix of the mitochondria.
Once this series of reactions is completed, Carbon Dioxide and
Hydrogen ions are produced.
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The CO2 is removed via the lungs
The hydrogen ions enter the electron transfer chain.
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This occurs in the cristae of the mitochondria.
Electrons are removed from hydrogen and passed down the elctron
transfer chain providing energy to resynthesise 34 moles of ATP.
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The hydrogen is combined with oxygen to produce water.
Glucose
PFK
Lactic acid
2 ATP
Pyruvic acid
Sarcoplasm
LDH
Acetyl CoA
2 ATP
Kreb’s Cycle
2 CO2
Mitochondria
(matrix)
H
02
e-
24 ATP
Electron
transfer
chain
H20
Mitochondria
(cristae)
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Advantages
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A large amount of ATP
can be resynthesised
 36 to 38 moles can
be produced from
one mole of
glycogen.
Activity can last for
hours
There are no harmful
by-products of the
chemical reactions
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Disadvantages
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Due to the need for
oxygen, the system
cannot resynthesise
ATP immediately;
there is a delay while
oxygen is transported
from the lungs
Cannot provide ATP
whilst working at
higher intensities.
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The threshold of any system is the point at
which that energy system is unable to provide
energy.
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PC system
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Lactic Acid system
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Approx. 10 seconds
Approx. 15 -180 secs
Aerobic system
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Onset of Blood lactate accumulation (OBLA)
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When blood lactate levels goes above 4mmol per litre or the
point at which there is a rapid increase in this value.
OBLA ranges from 50% VOs max in untrained individuals to
85% VO2 max in highly trained athletes.
 Due to increased ability to remove waste products and
supply oxygen to working muscles.
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In an given situation our energy systems
rarely work in isolation.
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E.g a footballer
Movement at low intensity whilst jogging back into
position
 Sudden high intensity movement – break down the
wing.
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Energy is provided by all three systems,
and the contribution is determined by the
intensity and the duration of exercise.
Duration of maximal exercise
Seconds
Minutes
10
30
60
2
4
10
30
60 120
Percentage
anaerobic
90
80
70
50
35
15
5
2
1
Percentage
aerobic
10
20
30
50
65
85
95
98
99
Aerobic
Anaerobic
100m sprint
0
100
200m sprint
10
90
100m swim
20
80
boxing
30
70
800m
40
60
1500m / hockey game
50
50
400m swim
60
40
rowing 2000m
70
30
3000m run
80
20
Cross-country run
90
10
100
0
Marathon
Adapted from Davis et al (2005) - Physical Education and the study of Sport
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Carnell et al (2002), Advanced PE for OCR
AS
Davis et al (2005), Physical Education and
the Study of Sport.