Anatomy of the Respiratory System

What are the main functions of the respiratory system?

Gaseous exchange

Air transport

Respiratory protection

Phonation

Olfaction

Nasal Cavity

Vestibule

Conchae

Surrounding sinuses

Pharynx

Nasopharynx

Oropharynx

Laryngopharynx

Larynx

Spchincter

Phonation

What is the difference between the conducting and respiratory portions?

The conducting portion warms, humidifies, and filters air; the respiratory portion performs gaseous exchange.

Where does the trachea begin and where does it divide?

Begins at the cricoid cartilage (C6)

divides at the carina (T4)

Toracic wall

Functions = respiration/ breathing

Protection

Musculoskeletal

What skeletal elements form the thoracic wall?

12 thoracic vertebrae, ribs with costal cartilages, and the sternum.

Thoracic Vertebrae

Body - heart shaped, facets for heads of ribs

Vertebral canal - Round

Transverse process - Facet for tubercles of ribs

Spinous proces - Slopes inferiorly

Atypical vertebrae - T1, T10 - T12

Sternum

Green = Manubrium

Blue = Body

Purple = Xiphisternum

Rib

intercostal vein and artery sit in the costal groove

2 floating ribs

Costochondral joints

What are the three layers of intercostal muscles?

External

Internal

Innermost intercostal muscles

Neurovascular bundle in costal groove (remember: VAN)

Intercostal vein

Intercostal artery

Intercostal nerve

What are the three major openings in the diaphragm and their vertebral levels?

Inferior vena cava (T8)

Oesophagus (T10)

Aorta (T12).

Which nerve supplies motor innervation to the diaphragm?

Phrenic nerve (C3, C4, C5).

What is the difference between the parietal and visceral pleura?

Parietal pleura lines the thoracic cavity; visceral pleura closely covers the lung surface.

Pleural cavity

Contains small amont of fluid to elimate friction and allow layers to glide smoothly

How many lobes do the right and left lungs contain?

Right lung has three lobes; left lung has two lobes.

Which fissure is found in the right lung only?

The horizontal fissure.

What is the arrangement of major structures at the lung hilum?

Bronchi are posterior, pulmonary artery is superior, and pulmonary veins are anterior and inferior.

Trace the pathway of the bronchial tree from the trachea to the alveoli.

Trachea -> main bronchi -> lobar bronchi -> segmental bronchi -> bronchioles -> alveoli.

What is the primary function of the alveoli?

Thin-walled sacs responsible for gas exchange.

What is the function of the bronchial arteries?

Supply most of the bronchial tree and visceral pleura.

What is the function of the pulmonary arteries?

Supply the alveoli with deoxygenated blood.

What is the effect of parasympathetic stimulation on the airways?

Bronchoconstriction via the vagus nerve.

What is the effect of sympathetic stimulation on the airways?

Bronchodilation and vasoconstriction via the sympathetic trunk.

How does Boyle's Law apply to pulmonary ventilation?

Pressure is inversely proportional to volume (P = 1/V).