Chapter 10

What is the primary role of the respiratory system?

The respiratory system plays a crucial role in both pulmonary and cellular respiration.

What is pulmonary respiration?

involves ventilation, the mechanical process of moving air into and out of the lungs.

What are the two components of pulmonary respiration?

1. Ventilation (moving air into and out of the lungs) 2. Exchange of O2 and CO2 in the lungs.

What is cellular respiration?

O2 utilization and CO2 production by the tissues.

What is the purpose of the respiratory system during exercise?

1. Gas exchange between the environment and the body, ensuring a sufficient supply of oxygen to working muscles and removal of carbon dioxide. 2. Regulation of acid-base balance.

What is the normal pH of blood?

7.4, and the body tries to maintain it between 7.35 and 7.45.

What occurs during acidosis?

blood pH drops below 7.35.

What occurs during alkalosis?

blood pH rises above 7.45.

What conditions can affect respiration?

Chronic obstructive pulmonary disease (COPD) and asthma increase airway resistance.

Where does gas exchange occur in the lungs?

at the alveoli.

What is diffusion in the context of respiration?

random movement of molecules from an area of high concentration to an area of lower concentration.

What governs the rate of gas transfer (V gas)?

Fick's law of diffusion: V gas = (A/T) × D × (P1 − P2).

What are the main sections of the respiratory system?

1. Upper respiratory tract: nose, pharynx, larynx 2. Lower respiratory tract: trachea, bronchi, bronchioles, alveoli.

What is the conducting zone of the respiratory system?

includes the nose, pharynx, larynx, trachea, and bronchi, cleanses and humidifies the air.

What is the respiratory zone of the respiratory system?

respiratory bronchioles and alveoli, where gas exchange occurs.

What causes inspiration?

when the volume of the lungs increases, decreasing intrapulmonary pressure below atmospheric pressure.

What is expiration?

when the volume of the lungs decreases, increasing intrapulmonary pressure above atmospheric pressure.

What is airway resistance?

the resistance to airflow in the respiratory system, primarily dependent on the diameter of the airway.

How does COPD affect airway resistance?

COPD increases airway resistance by narrowing the airways.

What is tidal volume (TV)?

the amount of air inhaled or exhaled in one breath, approximately 500 ml at rest.

What is the normal breathing frequency at rest?

12-15 breaths per minute.

What is the effect of training on ventilation during exercise?

Following endurance training, ventilation is 20 to 30% lower at the same submaximal work rate.

What is the oxyhemoglobin dissociation curve?

illustrates the relationship between the partial pressure of oxygen (PO2) and the saturation of hemoglobin with oxygen.

How is carbon dioxide transported in the blood?

three ways: dissolved in plasma (10%), bound to Hb (20% as carbaminohemoglobin), and as bicarbonate (70%).