Mechanisms of breathing/lung capacity - Respiratory System

Breathing definition

Entrance and exit of air from the lungs

Ventilation definition

The term for the movement of air into the alveoli (where exchange takes place)

2 major actions take place when you breath in and out

1. inhalation/inspiration

• pulling air into lungs

2. Exhalation/Expiration

• push air out of lungs

function of the two actions of breathing

to bring O2 into the lungs, bring CO2 out of the lungs

what two flat muscles produce the exhalation and inhalation movements?

the Diaphragm and intercostal muscles

where is Diaphragm located

below the rib cage and separates thoracic cavity from abdominal cavity

Factors that influence lung capacity

Age, gender, size, body physical condition

Tidal Volume (TV)

• amount of air moving in and out of the lungs

• avg amount 500 mL

Inspiratory reserve Volume (IRV)

• amount of air you can forcibly take in beyond tidal volume

• 2100 - 3200 mL

Expiratory Reserve Volume (ERV)

• amount of air you can force out beyond tidal volume

• 1200mL

Vital capacity (VC)

• total amount of exchangeable air

• TV + IRV + ERV = VC

Residual Volume (RV)

• the amount of air that will always be in your lungs and cannot be expelled

• 1200 mL