Human Heart Conduction System and Lung Volumes: ECG, Respiratory Zones, and Spirometry

What is the function of the Sinoatrial (SA) node?

It acts as the pacemaker of the heart, initiating depolarization.

What role does the Atrioventricular (AV) node play in the heart's conduction system?

It passes depolarization to the ventricles and includes a brief delay to allow for ventricular filling.

What are Bundle Branches responsible for?

They connect the atria to the left and right ventricles.

What do Purkinje fibers do?

They spread the wave of depolarization throughout the ventricles.

What does the P wave represent in an ECG?

Atrial depolarization.

What does the QRS complex indicate in an ECG?

Ventricular depolarization and atrial repolarization.

What does the T wave represent in an ECG?

Ventricular repolarization.

What might ECG abnormalities indicate?

They may indicate coronary heart disease.

What is the primary function of the respiratory system?

To conduct air to the respiratory zone and facilitate gas exchange between air and blood.

What are the main components of the conducting zone?

Trachea, bronchial tree, and bronchioles.

What components make up the respiratory zone?

Respiratory bronchioles and alveolar sacs.

What is vital capacity (VC)?

The maximum amount of gas that can be expired after a maximum inspiration.

What is residual volume (RV)?

The volume of gas remaining in the lungs after maximum expiration.

What does total lung capacity (TLC) refer to?

The amount of gas in the lungs after a maximum inspiration.

What is inspiratory reserve volume (IRV)?

The extra air that can be forcibly inhaled after a normal breath.

What does spirometry measure?

Lung volumes such as inspiratory reserve volume (IRV), tidal volume (TV), and expiratory reserve volume (ERV).

What are the components of lung capacities measured by spirometry?

Inspiratory capacity (IC), vital capacity (VC), and total lung capacity (TLC).

What is the formula for gas diffusion?

V gas = rate of diffusion, A = tissue area, T = tissue thickness, D = diffusion coefficient of gas, P1 - P2 = difference in partial pressure.