1. Blood Vessels
1.1. veins
1.2. arteries
1.3. venules
1.4. arterioles
2. Lungs
2.1. Physical Structure
2.1.1. thoracic cavity
2.1.2. bronchioles
2.1.3. alveolar duct
2.1.4. alveolar sacs
2.1.5. trachea
2.2. Mechanism
2.2.1. respiratory muscles
2.2.1.1. diaphrgam
2.2.1.1.1. inhale
2.2.1.1.2. exhale
2.2.1.2. intercostal muscle
2.2.1.2.1. inhale
2.2.1.2.2. exhale
2.2.2. gas exchanges
2.2.2.1. alveoli
2.2.2.1.1. partial pressure
2.2.2.1.2. diffusion
2.2.2.2. blood capillaries
2.2.2.2.1. transportation
2.2.3. Transition inhalation and exhalation
2.2.3.1. respiratory centres
2.2.3.2. chemoreceptors
2.2.3.3. medulla oblongata
2.2.3.4. central nervous system
3. Heart
3.1. Physical Structure
3.1.1. atria
3.1.2. ventricle
3.1.3. valves
3.1.3.1. sound
3.1.4. septum
3.2. Mechanism
3.2.1. impulse
3.2.1.1. SA node
3.2.1.1.1. AV node
3.2.2. systole
3.2.2.1. atria contract
3.2.2.2. ventricle contract
3.2.3. diastole
3.2.3.1. ventricle relax
3.2.3.2. atria relax
3.2.4. cardiac cycle
3.2.4.1. events the flow of blood
3.2.4.1.1. systemic circulation
3.2.4.1.2. pulmonary cirulation
3.2.4.2. ECG graph
3.2.4.2.1. electrical activity of heart