B3.1 Respiratory system (SL)

These flashcards cover key terms and concepts related to the respiratory system, including gas exchange, lung anatomy, and the mechanics of breathing.

Gas Exchange

The process by which organisms exchange gases with their environment to maintain survival.

Aerobic Respiration

A metabolic process that requires oxygen to produce ATP.

Carbon Dioxide

A waste product of metabolism that must be removed from the body to maintain pH balance.

Concentration Gradient

A difference in the concentration of a substance across a distance, crucial for efficient gas exchange.

Alveoli

Spherical air sacs in the lungs where gas exchange occurs, surrounded by capillaries.

Pneumocytes

Cells in the alveoli; Type I are responsible for gas exchange, and Type II secrete pulmonary surfactant.

Surfactant

A substance secreted by Type II pneumocytes that reduces surface tension in alveoli.

Ventilation

The process of moving air into and out of the lungs to facilitate gas exchange.

Diaphragm

The primary muscle involved in breathing, contracting to increase thoracic volume.

Lung Capacity

The volume of air the lungs can hold, measured in various ways like tidal volume and vital capacity.

Inspiratory Muscles

Muscles involved in inhalation, including the diaphragm and external intercostals.

Expiratory Muscles

Muscles involved in exhalation, such as the internal intercostals and abdominal muscles.