GCSE PE: Cardiac Cycle and Pathway of Blood

Introduction

• Overview of the cardiac cycle
• Pathway of blood in the heart
• Key terms and equations

Heart Orientation

• Left and right sides of the heart in images:
  • Oxygenated side (left in images)
  • Deoxygenated side (right in images)

Pathway of Blood

Right Side of the Heart (Deoxygenated Blood)

• Right Atrium: Entry point for deoxygenated blood
• Tricuspid Valve: Blood passes into the right ventricle
• Right Ventricle: Pumps blood into the pulmonary artery
• Pulmonary Artery: Transports deoxygenated blood to the lungs

Gas Exchange in the Lungs

• Red blood cells appear blue (illustration of high CO2)
• CO2 diffuses from capillaries to alveolus
• Oxygen diffuses to red blood cells, turning them red

Left Side of the Heart (Oxygenated Blood)

• Pulmonary Vein: Transports oxygenated blood to the left atrium
• Left Atrium: Blood passes through bicuspid valve
• Left Ventricle:
  • Thicker muscular wall
  • Pumps oxygenated blood to the rest of the body
• Aorta: Large artery transporting oxygenated blood away from the heart

Exercise and Aerobic Respiration

• CO2 buildup in muscles from aerobic respiration
• Veins transport deoxygenated blood back to heart
• Vena Cava: Returns deoxygenated blood to right atrium

Key Definitions and Equations

• Cardiac Output:
  • Amount of blood ejected per minute
  • Formula: Cardiac Output = Stroke Volume x Heart Rate
• Stroke Volume: Blood ejected per contraction
• Heart Rate: Number of beats per minute
• Diastole: Relaxation phase of the cardiac cycle
• Systole: Contraction phase of the cardiac cycle

Conclusion

• Key concepts are crucial for GCSE PE and relevant for biology
• Encouragement to subscribe and engage with the content

Make sure to review this information for your exams, as it's essential for GCSE PE and beneficial for understanding broader scientific concepts.