Respiratory System

Respiratory system

Brings oxygen into the body and to carry carbon dioxide out of the body; phonation, body temperature regulation, acid base balance, and olfaction

Chondromalacia

The softening (chondromalacia) of the cartilage rings that support the trachea (windpipe); cause of tracheal collapse (goose cough when excited common in toy breeds)

Nose

Site where air molecules first enter the respiratory system; begins with nostrils (nares), the external openings of the respiratory tube leading to nasal passages

Stenosis

abnormal narrowing of a body passageway, blood vessel, or space; nasal stenosis is common in brachiocephalics

No stenosis (open nostrils)

Level of stenosis

Mild

Level of stenosis

Moderate

Level of stenosis

Severe

Level of stenosis

Nasal passages

Located between the nostrils and the pharynx; seperated into left/right halves by the nasal septum; hard and soft palate seperates nasal cavity from oral cavity

Turbinates

Thin scroll like bones covered with nasal epithelium; divide each nasal passage into 3

Warming, humidifying, filtering

Three main conditioning roles of nasal passages

Allow air filtration before lungs (first line of defense)

Function of the turbinates

Paranasal sinuses

Outpouchings of the nasal passages that are contained within spaces in certain bones; examples are frontal and maxillary sinus

Ciliated lining

Sweep mucus produced in the sinuses down into the nasal passages

Prevents fluid and debris accumulation and the obstruction of nasal opening

Cilia function in the sinuses

Pharynx

Common passageway for both respiratory and digestive systems; the “throat”

Soft palate

Division between the dorsal nasopharynx and ventral oropharynx

Dorsally, ventral

Respiratory passageway starts ________ but as it comes caudally it becomes ________ to the digestive system

Larynx

Connects pharynx to trachea; made up of cartilage segments supported by the hyoid; the “voice box”

Epiglottis, arytenoid, thyroid, crioid

Cartilages of the larynx rostal to caudal

Epiglottis

Leaf-shaped rostal-most cartilage of the larynx; projects forward into the pharynx and pulled back to covering larynx opening when swallowing

Vocal cords

Attached to the arytenoid cartilages; muscles adjust the tension of the vocal cords by moving the cartilages

2

The larynx has _ fibrous connective tissue bands, as air passes over the cords they vibrate creating a sound

Less

As there is ____ tension in the vocal cords, sounds that come out are lower pitched

More

As there is ____ tension in the vocal cords, sounds that come out are higher pitched

Trachea

Tube of fibrous tissue and smooth muscle with cartilaginous rings (ciliated) that extends from the larynx to where it divides into the two main bronchi; the “windpipe”

Bifurcation of the trachea

The division of the trachea into two main bronchi

Cartilaginous rings of the trachea

Incomplete rings of hyaline cartilage spaced evenly along the length of the trachea, “C shaped”

Mucociliary escalator

Structure in the trachea where mucus traps small particles and cilia carry oit back to the pharynx to be swallowed

Lower respiratory tract

Tract that begins with the bronchi and ends with alveoli; comprised mostly of air passageways

Base (contact with diaphragm), apex, convex lateral surgace

Portions of the lung

Diaphragm

Thin muscle that directly aids in respiration

Mediastinum

Between the left and right sides of the lungs

Lung lobes

Left cranial (2 sections), left caudal, right cranial, right middle, right caudal, and right accessory

Nonfunctional

Before birth, the lungs of a fetus are (fully functional/nonfunctional)

Floats

A piece of lung tissue was placed into water, you can tell if a baby has died before birth if the lung _____ because there is no air in it

Bronchial tree

Air passageways that lead from the bronchus to the alveoli; diameter can be adjusted by smooth muscle fibers that line the wall; divides into smaller and smaller branches; begins at tracheal bifurcation

Relaxes

During times of intense exercise, the bronchial smooth muscle _____ allowing the air passageways to dilate and move more air

Constrict

When relaxed, smooth muscle fibers in the bronchial tree _______ to lessen amount of work

Tracheal bifurcation, principal bronchi (left and right), labor bronchi, segmental bronchi, bronchioles, alveolar ducts, alveoli

Flow of air in the brochial tree (cranial to caudal)

Alveolar sacs

Groups of alvoli at the end of alveolar ducts; resembles bunches of grapes

Alveoli

Site of external respiration (oxygen exchanged between blood and air for carbon dioxide); tiny and thinned wall sacs (composed of thin epithelium) surrounded by networks of capillaries

Asthma

Causes the brochial tree to becomes overly sensitive to certain irritants; exposure to irritants causes brochoconstriction that can range from mild-severe; frantic attempts for air can cause wheezing, coughing, dyspnea, and cyanosis

Emphysema

Damages the alveoli sacs, enlarges sacs and increases lung surface area; old air becomes trappped during exhalation as new air cannot enter the alveolar sacs and supply oxygen to the blood system