Anatomical structures

Nasal septum

Divides the nasal cavity into left and right sides.

Nasal conchae (superior) (meatus nasi superior)

bony shelf

Nasal meatuses (superior)

air passage

Paranasal sinuses

Air-filled cavities connected to the nasal cavity; increase mucosal surface area.

Olfactory region

Contains receptors responsible for smell.

Hard palate (palatum durum)

Forms the floor of the nasal cavity (podniebienie)

Soft palate (palatum molle)

Elevates during swallowing to close off the nasal cavity from the pharynx.

Nasopharynx

Contains the pharyngeal tonsil and openings of the auditory tubes.

Oropharynx

Communicates with the oral cavity; passage for air and food.

Laryngopharynx

Shared passage leading toward the larynx and esophagus.

Pharyngeal tonsil (adenoid)

high up in the throat, behind the nasal cavity on the roof and posterior wall of the nasopharynx

Tubal tonsils

in the nasopharynx

Palatine tonsils

at either side of the lateral wall of the oropharynx

Lingual tonsil

at the root of the tongue

Waldeyer’s ring

Ring of lymphoid tissue providing early defense against pathogens.

Hyoid bone

Associated with the larynx and supports structures involved in swallowing.

Thyroid cartilage

Supports and protects the glottis and entrance to the trachea; Adam’s apple

Cricoid cartilage

Supports and protects the glottis and entrance to the trachea.

Epiglottis

Folds backward during swallowing to help prevent food and liquid entering the respiratory tract.

Arytenoid cartilages

Move and adjust vocal-fold position and tension.

Glottis

Opening between the vocal folds.

Vocal folds

Vibrate to produce sound; adduction closes the glottis, consists of:

1. Mucous membrane

2. Vocal ligament

3. Vocalis muscle

Vestibular folds

False vocal folds; lie above the vocal folds and are not responsible for normal sound production.

Intrinsic laryngeal muscles

Move laryngeal cartilages relative to each other

Extrinsic laryngeal muscles

Move and stabilize the larynx as a whole.

Superior laryngeal nerve

Branch of the vagus nerve; supplies the upper larynx.

Recurrent laryngeal nerve

Branch of the vagus nerve; supplies the lower larynx and intrinsic laryngeal muscles.

Trachea

Conducts air; supported by C-shaped cartilage rings.

Tracheal cartilages

Keep the trachea open; C-shaped rings leave a posterior opening for the esophagus.

Trachealis muscle

Smooth muscle spanning the posterior tracheal wall; contraction narrows the trachea.

Carina

Internal ridge at the tracheal bifurcation separating the openings of the primary bronchi.

Right primary bronchus

Wider and descends at a steeper angle than the left; aspirated foreign bodies are more likely to enter it.

Left primary bronchus

Main airway carrying air into the left lung.

Secondary (lobar) bronchi

Supply the lung lobes; three on the right and two on the left.

Tertiary (segmental) bronchi

Supply bronchopulmonary segments.

Bronchioles

Smaller conducting airways; cartilage progressively decreases and is absent in bronchioles.

Terminal bronchioles

Last part of the conducting portion before the respiratory portion; contain smooth muscle but no cartilage.

Alveolar ducts

Conduct air toward the alveoli; part of the respiratory portion.

Alveoli

Main sites of gas exchange between air and pulmonary capillary blood.

Respiratory mucosa

a specialized mucous membrane lining the upper and lower respiratory tracts, warms the air coming in

Cilia

Move mucus and trapped particles toward the pharynx.

Lamina propria

a thin layer of loose (areolar) connective tissue that lies directly beneath the surface epithelium in mucous membranes (mucosa) across the body

Right lung

divided into three lobes: the superior, middle, and inferior lobes, contains two fissures: an oblique fissure and a horizontal fissure

Left lung

divided into two lobes: the superior and inferior lobes, contains only one fissure: the oblique fissure

Horizontal fissure

Separates the superior and middle lobes of the right lung.

Oblique fissure

Separates lung lobes; present in both lungs.

Apex of lung

Hilum of lung

Passage for the primary bronchus

Visceral pleura

Serous membrane directly covering the lung. (purple on the picture)

Parietal pleura

Serous membrane lining the thoracic wall (navy on the picture)

Pleural cavity

Space between the visceral and parietal pleura; contains lubricating pleural fluid. (blue on the picture)

Pleural fluid

In the pleural cavity. Reduces friction between pleural surfaces during breathing.

Mediastinum

Central thoracic compartment separating the lungs; contains the heart.

Diaphragm

Primary muscle of inhalation; contraction moves it downward and increases thoracic volume.

External intercostal muscles

Elevate the ribs during inhalation.

Internal intercostal muscles

Assist forceful exhalation by depressing the ribs.

Sternocleidomastoid muscle

Accessory muscle of forceful inhalation; helps elevate the sternum.

Scalene muscles

Accessory muscles of inhalation; elevate the first and second ribs.

Pectoralis minor muscle

Accessory muscle that can assist inhalation by elevating the ribs when the shoulder girdle is fixed.

Serratus anterior muscle

Accessory muscle that can assist inhalation when the shoulder girdle is stabilized.

Transversus thoracis muscle

Assists forceful exhalation.

External oblique muscle

Compresses the abdomen during forceful exhalation.

Internal oblique muscle

Compresses the abdomen during forceful exhalation.

Rectus abdominis muscle

Compresses the abdomen during forceful exhalation

Pulmonary artery

Carries deoxygenated blood from the heart to the lungs for gas exchange.

Pulmonary veins

Carry oxygenated blood from the lungs to the heart.

Bronchial arteries

Supply the lung tissue itself; distinguish them from pulmonary vessels involved in gas exchange.

Sphenoidal sinus

frontal sinus

nares (nostril)

nasal conchae (middle) meatus nasi medius

nasal conchae (inferior) meatus nasi inferior

Palatum durum