Human AP I (lecture): Exam 5, Respiratory (study guide)

What are the components of the upper respiratory tract?

Nose, nasal cavity, paranasal sinuses, pharynx

What are the key functions of the upper respiratory tract?

Filters air, warms and humidifies air, provides sense of smell, contributes to voice resonance

What are the components of the lower respiratory tract?

Larynx, trachea, bronchi, bronchioles, alveoli, lungs

What are the key functions of the lower respiratory tract?

Conducting air (larynx → bronchioles), gas exchange (respiratory bronchioles + alveoli)

What are the differences between the right and left lung?

The right lung has three lobes, while the left lung has two lobes.

What is the cardiac notch?

A concave space in the left lung that accommodates the heart.

What is a pulmonary lobule?

The functional unit of the lung, consisting of alveoli and surrounding structures.

How does airway structure change as airways branch?

Cartilage decreases, smooth muscle increases, epithelium becomes thinner.

What are the components of the respiratory defense system?

Mucus production, cilia (mucociliary escalator), filtration in nasal cavity, alveolar macrophages.

What are the types of cells in the alveoli?

Type I pneumocytes (gas exchange), Type II pneumocytes (surfactant), macrophages (debris removal).

What are the three layers of the blood-air barrier?

Alveolar epithelium, fused basement membranes, capillary endothelium.

What happens during inspiration?

Diaphragm contracts, thoracic cavity expands, pressure inside lungs decreases, air flows in.

What happens during expiration?

Muscles relax, thoracic cavity volume decreases, pressure inside lungs increases, air flows out.

What drives airflow in the lungs?

Air flows from high pressure to low pressure; intrapulmonary pressure changes drive airflow.

What is tidal volume (TV)?

The amount of air inhaled or exhaled during normal breathing.

What is vital capacity (VC)?

The maximum amount of air a person can exhale after maximum inhalation.

What is Henry's Law?

Gases dissolve into liquids based on partial pressure.

How is oxygen primarily transported in the blood?

Mostly carried bound to hemoglobin.

How is carbon dioxide primarily transported in the blood?

Mostly carried as bicarbonate ions (HCO₃⁻).

What regulates breathing?

Medulla oblongata (basic rhythms), pons (modifies rhythm), chemoreceptors (monitor CO₂, O₂, pH).

What is the most important regulator of breathing?

CO₂ levels, via pH changes.

What are the functions of the nasal cavity?

Warms air, humidifies air, helps with immune defense.