Bio question about respiration?

Question

What are the basic steps of gas exhange (respiration) in the body?

Answer 1

Gas transport: Oxygen in and Carbon Dioxide out

Ventilation: (atmosphere <-> respiratory zone)

Lung diffusion: (respiratory zone <-> erythrocyte/plasma)

Circulation: (blood flow carries erthyrocyte/plasma <-> tissue)

Tissue diffusion: (erythrocyte/plasma <-> tissue cells)

Internal respiration: (cellular metabolism using O2 & producing CO2)



VENTILATION: Structure and Function



A. Gas conduction:

Upper respiratory tract: Gas humidification, filtration, and warming

Conducting airways: Gas distribution to respiratory zone

Trachea: Cartilage rings

Bronchi: Cartilage plates

Bronchioles: No cartilage -> depend upon lung structure

Total cross-sectional area of conducting airways INCREASES as we move from the trachea to the respiratory zone.

VELOCITY (cm/sec) = FLOW (cm3/sec) / CROSS-SECTION AREA(cm2). Therefore in the periphery of the lung near the respiratory zone gas velocity drops to zero and there is no CONVECTIVE movement of gas. Movement of gas in the respiratory zone is by DIFFUSION alone.

Terminal bronchioles of conducting airways have ciliated and goblet cells to help clear particulate matter.

Respiratory bronchioles mark the beginning of the respiratory zone and have alveoli in their walls.



Negative Pressure Breathing:



Pump Structure:

Rib cage and spine

Diaphragm

Intercostal muscles

Respiratory control is a complex, integrated phenomenon with voluntary and involuntary controls.