Anatomy of the Respiratory System - Week 3

Functions of the Respiratory System

Deliver O2, remove CO2, regulate blood pH, smell, filter air, produce sound, and excrete water and heat.

Upper Respiratory Tract Structures

Nose, mouth, and pharynx.

Lower Respiratory Tract Structures

Larynx, trachea, bronchi, and lungs.

Conducting Zone Structures

Nose, mouth, pharynx, larynx, trachea, bronchi, bronchioles, and terminal bronchioles.

Respiratory Zone Structures

Respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli.

Nose Functions

Warm, moisten, and filter air; detect olfactory stimuli; act as a resonance chamber for speech.

Larynx Function

Prevent food entry into the trachea via the epiglottis and produce voice via vocal folds.

Type I Alveolar Cells

Form the main site of gas exchange in the alveoli.

Type II Alveolar Cells

Produce alveolar fluid containing surfactant.

Alveolar Macrophages

Phagocytes that consume dust and debris in the alveoli.

Pleura Function

Surround and protect lungs, and secrete fluid to reduce friction.

How does deoxygenated blood enter the lungs?

Deoxygenated blood enters via pulmonary arteries.

What happens to deoxygenated blood in the lungs?

Deoxygenated blood becomes oxygenated following gas exchange in alveoli.

How does oxygenated blood return to the heart?

Oxygenated blood returns to the heart via four pulmonary veins.

Which chambers of the heart does oxygenated blood move through?

Oxygenated blood moves through the left atrium and ventricle.

How does oxygenated blood exit the heart?

Oxygenated blood exits the heart through the aorta.

What is the pathway of deoxygenated blood from the heart to the lungs?

Deoxygenated blood passes through the pulmonary trunk into left and right pulmonary arteries, which enter the lungs.

Bronchial Arteries Function

Provide oxygen-rich systemic blood to the lung tissues, including bronchi and connective tissue.

Bronchial Arteries Origin

Branch directly from the thoracic aorta.

Bronchial Veins Function

Drain deoxygenated blood from the larger bronchial walls and surrounding lung structures.

Bronchial Veins Drainage

Drain into the azygos and hemiazygos systems.

Hilum

Houses bronchial tree.

Alveoli

Main site of gas exchange.

Alveolar Sacs

Passageway for air. Small amount of gas exchange.

Alveolar Ducts

Passageway for air. Small amount of gas exchange.

Respiratory bronchiole

Passageway for air. Small amount of gas exchange.

Conducting Zone Air Pathway

Nose and nasal cavity -> Pharynx -> Larynx -> Trachea -> Main (primary) bronchi -> Lobar (secondary) bronchi -> Segmental (tertiary) bronchi -> Bronchioles -> Terminal bronchioles

Terminal Bronchioles

Passageway for air.

Bronchi

Passageway for air.

Main (primary) bronchus

Passageway for air.

Lobar (secondary) bronchus

Passageway for air.

Segmental (tertiary) bronchus

Passageway for air.

Trachea

Passageway for air.

Trachea Cartilage

Provides structural support to keep the airway open.

Oesophagus

Muscular tube that connects the pharynx to the stomach.

Pharynx

Passageway for air