13. Energy Flashcards
What is a calorie?
A measure of energy in the form of heat.
- 1 calorie is the energy/heat required to raise the temperature of 1 gram of water 1oc.
What energy substance is used to drive a muscle contraction?
Adenosine Triphospate (ATP)
What molecules is ATP made up of?
1x adenosine
1x ribose
3x phosphate
Where does ATP store energy within its molecule/?
In the bonds between the phosphate groups
When a muscle contracts what happens to ATP?
It becomes ADP by releasing energy (-12kcal in vivo)
Which aids the breaking down of the bond between the 2nd and 3rd phosphate groups?
ATPase
What happens to the free phosphate ion after hydrolysis?
Usually transferred to another molecule
What does ADP become when the first and second phosphate groups are broken?
ADP becomes adenosine monophosphate (AMP)
How many times is an ATP molecule recycled in a day?
2,000-3,000 times
What is respiration?
Chemical process where organic compounds (carbs and fats) release energy
What are the 2 anaerobic respiration systems used to restore ATP?
Creating phosphate
Lactic acid
Where does aerobic / anaerobic respiration occur?
Aerobic: Mitrochondria
Anaerobic: Cytoplasm
What:
- happens to the glucose
- is the ATP Yield
- else does it produce
..in Aerobic/anaerobic respiration
Aerobic:
- Complete oxidation of glucose
- High ATP yield
- CO2 and Water
Anerobic:
- Glycolysis of glucose (not fully broken)
- Low ATP yield
- Lactic acid
Which substrate is used in the
- Creating phosphate system (anaerobic)
- Lactic Acid system (anaerobic)
- Aerobic system
- CP - creative phosphte
- Lactic acid - Glucose
- Aerobic - Glucose, fatty acids, amino acids
How does creating phosphte turn ADP into ATP?
By donating it’s phosphte group
How long would it take to replenish 50% and 100% of your creating phosphate stores?
50% = 30 seconds 100% = 2-3 minutes
When high intensity, short duration muscle contraction is required which system supplies the energy?
The creatine phosphate system
Where can creatine phosphte be obtained from?
Meat
Internal production by liver and kidneys
Glucose is broken down to create puruvic acid, where does it go to do this?
Either
- The mitochondria for slow ATP by aerobic respiration.
- Concerted to lactic acid to allow ATP to be synthesised.
From lactic acid we create pyruvic acid and ATP, but we also create ________ what does this mean?
Also create acidic hydrogen ions which causes acidic state - the reason lactic acid is wrongly blamed for fatigue
For high intensity exercises for a longer period, which system is used?
Lactate system
If the need for energy is high/fast and sufficient oxygen can not be provided, what happens (in lactate system)?
Pericardium is converted into lactic acid and hydrogen ions
Which system produces the largest amount of ATP and what are its downfalls?
Aerobic system, however is a slower process and takes longer to start
After glycolysis has occurred and pyruvic acid is produced, what happens?
The kerbs cycle (series of chemical reactions) breaks down pyruvic acid and continues production of ATP.
What new molecule does pyruvate become in the aerobic system?
Acetyl CoA
How many ATP molecules are produced from each system?
- CP = 1x ATP (by contributing 1x CP molecule)
- Anaerobic = 2x ATP (from each glucose molecule through glycolysis)
- Aerobic = 36-38 ATP (from each glucose molecule)
What 3 factor determine the energy system used?
- How quick is ATP needed? - intensity below/above 75% MHR
- How much/long ATP? - duration below/above 2 minutes
- Availability of substrates to support the system - CP can sustain 3-15 seconds
Glycogen 2 hours moderate intensity
Fat can sustain longer than can exercise for
Which system would be used for
- short duration 6-10 secs
- high intensity 10-90 secs
- 1 min-3+ hours
- CP 6-10 seconds
- Lactate 10-90 seconds
- Aerobic 1 min-3 hours
What is power?
Sum of the maximal speed at which ATP can be replenished and made available
What is capacity?
how much ATP can be provided
When the body can’t supply sufficient oxygen anymore, which system is used for energy production and what is this state called?
Lactate system takes over
Called the Anaerobic threshold
What happens when the anaerobic threshold approaches?
Anaerobic system makes up for the shortfall of the aerobic pathways that can’t keep up.
Carbon dioxide production is raised and must be removed so ventilation rates increase.
How is anaerobic threshold expressed?
Maximum heart rate and VO2 max
