A&P II – Respiratory System Vocabulary

Vocabulary flashcards summarizing essential respiratory terms for Exam 3 study.

Respiratory System

Body system responsible for gas exchange, air conduction, sound production, olfaction, protection, pH and blood-pressure regulation.

Gas Exchange

Process of O2 moving from alveoli to blood and CO2 moving from blood to alveoli or tissues.

Mucosal Lining

Inner respiratory tract surface covered with mucus that traps debris and pathogens.

Mucus

Sticky secretion that protects respiratory surfaces by trapping particles and microorganisms.

Larynx

Cartilaginous structure that serves as an air passage, prevents food entry, produces sound, and aids pressure regulation.

Pitch (voice)

Tone of sound determined by tension of vocal cords.

Vocal Range

Overall high-to-low span of a voice, set by the length and thickness of vocal folds.

Volume (voice)

Loudness of sound controlled by the force of airflow across vocal cords.

Laryngitis

Inflammation of the larynx causing hoarseness or loss of voice.

Bronchitis

Inflammation of the bronchi; can be acute or chronic.

Asthma

Disorder marked by hypersensitive airways, bronchoconstriction, and difficulty breathing.

Alveoli

Microscopic air sacs where gas exchange occurs in the lungs.

Type I Alveolar Cells

Squamous cells forming the majority of the alveolar wall and permitting gas diffusion.

Type II Alveolar Cells

Cells that secrete surfactant to reduce surface tension inside alveoli.

Surfactant

Lipid-protein fluid that lowers alveolar surface tension, preventing collapse.

Alveolar Macrophages

Immune cells that remove debris and pathogens from alveoli.

Respiratory Membrane

Thin barrier (alveolar epithelium + capillary endothelium) across which O2 and CO2 diffuse.

Segmented Lungs

Anatomical divisions that allow isolation of damaged lung areas.

Pulmonary Circulation

Blood flow from heart to lungs for gas exchange.

Bronchial Circulation

Systemic blood flow that nourishes lung tissues themselves.

Pleura

Serous membrane enveloping lungs and lining thoracic cavity.

Serous Fluid (pleural)

Lubricating fluid between pleural layers that reduces friction and helps maintain lung inflation.

Pulmonary Ventilation

Breathing; movement of air into and out of lungs.

Medulla Oblongata

Brainstem region that sets basic respiratory rhythm.

Pons

Brainstem region that fine-tunes breathing rhythm generated by the medulla.

Chemoreceptors

Sensors that detect changes in blood or CSF levels of CO2, O2, and pH to influence breathing.

O2-Hemoglobin Saturation Curve

S-shaped graph showing the percentage of hemoglobin bound to oxygen at various PO2 levels; shifts with pH, CO2, and temperature.

Hyperventilation

Breathing rate/depth above metabolic needs, lowering CO2 and causing alkalosis.

Hypoventilation

Breathing rate/depth below metabolic needs, raising CO2 and causing acidosis.

Hyperpnea

Increased breathing depth/rate that matches metabolic demand, as during exercise.

Altitude Sickness

Illness from low atmospheric PO2 leading to hypoxia at high elevations.

Hypoxia

Deficiency of oxygen reaching the tissues.

Bicarbonate (HCO3−)

Primary form (≈70%) in which CO2 is transported in the blood.