Question

provide a summary of the respiratory system from the perspective of inhaled air. Your description should include:

- An organized progression of travel. What organs does the air travel through? What types of tissues and structures are seen within them? What purposes do those structures serve?

- Orientation of those organs within the body using correct directional and regional terminology. For example - it is not adequate to say that air is inhaled via the nose, you should include a description of where the nose is found and where air will progress (i.e. Air is inhaled via the nares in the facial region, and progresses posterior through the nasal cavity towards the naso-pharynx.)

Answer 1

functions of pharynx:

Passageway for air and food

Warming and humidifying

Hearing

Protection

Speech

LARYNX :

POSITION :The larynx or voice box links the laryngopharynx and the trachea. It lies in front of the laryngopharynx and the 3rd, 4th, 5th and 6th vertebrae.

STRUCTURE :

THE LARYNX IS COMPOSED OF SEVERAL IRREGULAR SHAPED CARTILAGES ATTACHED TO EACH OTHER BY LIGAMENTS AND MEMBRANES. THE MAIN CARTILAGES ARE 1 THYROID CARTILAGE , ONE CRICOID CARTILAGE, TWO ARYTENOID CARTILAGES ,ONE EPIGLOTTIS.

FUNCTIONS OF LARYNX:

Production of sound

Speech

Protection of the lower respiratory tract

Passageway for air

Humidifying, filtering and warming.

TRACHEA :

POSITION :

the trachea or wind pipe is a continuation of the larynx and extends downwards to about the level of 5th thoracic vertebrae where is devides at the carina into the right and left primary bronchi, one bronchus going to each lung.it is approximately 10 to 11 cm long and lies mainly in the median plane in front of the oesophagus.

STRUCTURE :

The tracheal wall is composed of three layers of tissue and is held open by between 16 and 20 incomplete c shaped rings of hyaline cartilage lying one above the other. the rings are incomplete posteriorly where the trachea lies against the oesophagus. These cartilages are embedded in a sleeve of smooth muscle and connective tissue which also forms the posterior wall where the rings are incomplete.

Three layers of the cartilages of trachea are:

The outer layer contains fibrous and elastic tissue and encloses the cartilages.

the middle layer consists of cartilages and bands of smooth muscle that wind around the trachea in helical arrangement.there is some aerola tissue containing blood and lymph vessels and autonomic nerves. the free ends of the incomplete cartilages are connected by the trachealis muscle, which allows for adjustment of tracheal diameter.

Functions of trachea:

support and patency

Mucociliary escalator

Cough reflex

Warming, humidifying and filtering.

LUNGS:

THERE ARE TWO LUNGS ONE LINE ON EACH SIDE OF THE MIDLINE IN THE THORACIC CAVITY.

They are cone shaped and have an apex, a base, costal surface and medial surface.

Pleura and pleural cavity :

the pleura consists of a closed sac of serous membrane which contains a small amount of serous fluid. the long is pushed into the sad so that it forms two layers one adheres to the lungs and other to the wall of the thoracic cavity.

BRONCHI AND BRONCHIOLES:

the two primary bronchi are formed when the trachea divides at the level of thoracic vertebrae.

the right bronchus is wilder shorter Anmol vertical than the left bronchus and therefore more likely to become obstructed by an in held foreign body it is approximately 2.5 cm long.after entering the right lung at the hilum it divides into three branches one to each lobe each branch then subdivided into numerous small branches

The left bronchus is about 5 cm long and is narrower than the right. after entering the lung at the hilum it divides into two branches.

the bronchial walls contain the three layers of tissue as the trachea and are lined with ciliated columnar epithelium.

Functions:

Control of air entry, warming and humidifying, support and patency, removal of particulate matter, cough reflex.

the muscles involved in the breathing for intercostal muscles and diaphragm.