Energy Systems

Question 1

Define energy

Answer 1

the ability to perform work (joules)

Question 2

Define chemical energy

Answer 2

energy from food

Question 3

Define potential energy

Answer 3

stored energy

Question 4

Define the equation of work

Answer 4

Work (joules)=force x distance

Question 5

Outline the three energy systems

Answer 5

There are 2 anaerobic stores and one aerobic store
These are ATP-PC System, Anaerobic glycolysis/Lactic acid system and the Aerobic system (glycolysis and lipolysis)

Question 6

What is energy?

Answer 6

Energy is the breakdown of ATP (Adenosine Triphosphate) in our cells

Question 7

What is the structure of ATP?

Answer 7

1 Adenosine molecule and 3 inorganic phosphate molecules
The phosphates are attached by ‘high energy’ which when broken release energy

Question 8

How long does ATP last for?

Answer 8

around 2-4 seconds

Question 9

What is the name of the enzyme that breaks down the bond in ATP?

Answer 9

ATPase

Question 10

The equation of the breakdown of ATP

Answer 10

ATP=ADP+Pi+Energy

Question 11

What are the 3 factors that affect the predominant energy system?

Answer 11

1. Intensity
2. Duration
3. Fitness levels

Question 12

Outline two key points of the ATP-Pc system

Answer 12

1. it is an anaerobic system
2. PC is found in the sarcoplasm of muscles
3. the substrate is PC
4. used for EXPLOSIVE exercise lasting for 8-10 SECONDS
5. most INEFFICIENT energy system
6. energy yield is 1mol of ATP per 1mol of PCr

Question 13

Describe how the ATP-Pc system works

Answer 13

1. PC is a compound stored in the muscle
2. CREATINE KINASE detects high levels of ADP
3. PC is the broken into P+C to release energy for ADP to combine with the extra phosphate released

PC~>Pi+C+[energy]~>ADP+Pi+[energy]~>ATP

Question 14

How long does it take for ~98% of PC stores to recover?

Answer 14

3 minutes of rest

Question 15

EXAM QUESTION (AO1)
When is the ATP-Pc system used predominantly and give some sporting examples?

Answer 15

Under the first few seconds of intense, explosive muscular activity (short, maximal movement)
e.g 100m sprinter or weight lifter

Question 16

Outline 2 key points from the Anaerobic glycolysis system

Answer 16

1. substrate is gluscose and glycogen
2. produces lactic acid
3. predominant for HIGH INTENSITY exercise and lasts for 3 MINUTES but PEAKS at 1 MINUTE

Question 17

Describe how the Anaerobic glycolysis system works

Answer 17

1. Glucose is broken down in the muscles
2. Energy is released to produce 2 ATP
3. Because of the absence of oxygen, pyruvic acid is converted into lactic acid (H+ ions and lactate)
4. As activity continues, lactic acid builds causing acidosis in the muscles causing muscle fatigue and discomfort, limiting performance

Glycogen ~> Glucose [ENERGY (2 ATP)] ~> Pyruvic Acid/2 pyruvate {no oxygen} ~> Lactic acid (H+ ions and Lactate)

Question 18

EXAM QUESTION
When is the Anaerobic Glycolysis used? and give some sporting example

Answer 18

high intensity exercise lasting 2-3 minutes

e.g 400-800m run and many team sports

Question 19

Outline two key points about the aerobic system

Answer 19

1. most EFFICIENT energy system but is the SLOWEST
2. in the presence of oxygen
3. used for long lasting events or exercises longer than 5 minutes

Question 20

Outline the three ways which aerobic system produces ATP

Answer 20

1. Krebs cycle
2. Electron transport chain
3. Beta oxidation

Question 21

How does the Aerobic glycolysis work?

Answer 21

1. Glycogen is broken down into glucose and then pyruvic acid/2 pyruvate. Enough energy is produced to make 2 ATP
2. Then in the presence of O2 pyruvic acid turns into Acetyl Choline A
3. This then goes into the krebs cycle where enough energy is produced to make 2 ATP
4. The H+ electrons join the electron transport chain which produces enough energy for 34 ATP

Glycogen~>Glucose [energy (2 ATP)]~> Pyruvic acid/2 pyruvate~>ACA~>Krebs cycle [energy (2 ATP)]~>Electron Transport Chain [energy (34 ATP)]

Question 22

How does aerobic lipolysis works?

Answer 22

Fats~>Glycerol & Free fatty acids~>Acetyl coenzyme A~>Krebs cycle [energy] ~>Electron Transport system [energy] (147 ATP)

Question 23

EXAM QUESTION
When is the aerobic system used? and give some sporting examples

Answer 23

LOW INTENSITY exercise and oxygen supplies are high for continuous exercise over 5 minutes

Question 24

Define energy continuum

Answer 24

Explains how the body uses different energy systems during physical activities

Question 25

EXAM QUESTION Describe the ATP-Pc system and identify one activity where it is predominantly used (3 marks)

Answer 25

1 mark: The ATP-PC system provides energy by breaking down phosphocreatine (PC) in the muscles. 1 mark: No oxygen is required (anaerobic process). 1 mark: Predominantly used in short, explosive activities like a 100m sprint or weightlifting.

Question 26

EXAM QUESTION Compare the anaerobic glycolysis system to the aerobic system in terms of duration and byproducts (4 marks)

Answer 26

1 mark: The anaerobic glycolysis system is used for high-intensity activity lasting up to 2 minutes, while the aerobic system is used for low-to-moderate intensity activity lasting several minutes to hours. 1 mark: Anaerobic glycolysis produces lactic acid as a byproduct. 1 mark: The aerobic system produces carbon dioxide and water as byproducts. 1 mark: The aerobic system produces more ATP (up to 36 ATP per glucose) compared to anaerobic glycolysis (2 ATP per glucose).

Question 27

EXAM QUESTION Explain the energy continuum and how it applies to a 400m runner (5 marks)

Answer 27

1 mark: The energy continuum shows how different energy systems contribute to physical activity depending on intensity and duration. 1 mark: At the start of the 400m race, the ATP-PC system is used for explosive energy (first 5-10 seconds). 1 mark: During the middle phase, the anaerobic glycolysis system dominates, providing energy without oxygen. 1 mark: Towards the end, the aerobic system contributes as oxygen becomes more involved. 1 mark: The energy systems overlap, but the anaerobic glycolysis system is the primary contributor in a 400m race due to its duration and high intensity.

Question 28

EXAM QUESTION Outline the key processes of the aerobic system and explain why it is ideal for marathon running (6 marks)

Answer 28

1 mark: The aerobic system uses oxygen to break down glucose or fat for energy. 1 mark: It begins with glycolysis, producing pyruvate, which enters the Krebs cycle. 1 mark: The Krebs cycle releases hydrogen, which is carried to the electron transport chain. 1 mark: The electron transport chain produces a large amount of ATP (up to 36 per glucose molecule). 1 mark: Byproducts are carbon dioxide and water, which are easily removed from the body. 1 mark: This system is ideal for marathon running as it provides a sustained energy supply for long-duration, low-intensity activities.

Question 29

EXAM QUESTION Evaluate the contribution of the three energy systems during a football match (8 marks)

Answer 29

Level 1 (1–2 marks): Basic knowledge of energy systems with little relevance to football (e.g., mentioning ATP-PC system and oxygen use). Level 2 (3–5 marks): Some understanding of how energy systems contribute during a football match, with examples (e.g., ATP-PC for short sprints, anaerobic glycolysis during intense runs). Level 3 (6–8 marks): Clear and detailed explanation of all three energy systems, applied directly to football. For example: ATP-PC system for explosive actions like sprints, jumps, and tackles. Anaerobic glycolysis during periods of high-intensity running or sustained effort. Aerobic system during recovery, jogging, and maintaining overall endurance. Reference to the energy continuum and overlapping of systems.