The structures and organs that function in air distribution and gas exchange.
In does the of the respiratory system aid?
- Filter, warm, and humidify the air breathed in
- Influence sound produciton
- Provide for the sense of smell
What are the subdivisions of the upper respiratory tract?
Allows for air intake and sense of smell
- Nares (Nostrils)
- Nasal Cavity
- Madian Nasal Septum
Median Nasal Septum
The nasal cavity is divided into right and left halves by hte nasal septum in the midline; this septum is formed by the perpendicular plate of the ehtmoid bone, vomer, and a septal cartilage.
A septum that is markedly off center is referred to as a deviated setpum; this condition is commonly a result of trauma to the nose.
3 conchae found per side in the nose; conchae are covered with ciliated mucous membranes that filter, warm, and humidify air.
Olfactory Receptor Cells
Receive chemicals interpreted as smells.
Air-filled spaces in the skull; mucous membrane lined; drain into nasal cavity.
- Frontal, ethmoid, sphenoid, maxillary
Inflammaiton of the sinus membrane
Separates nasal cavity from oral cavity (mouth)
Separates nasopharynx from oral cavity
Commonly known as throat
Connects nasal and oral cavities to the larynx and esophagus
A common tube for the respiratory and digestive systems
Region where the nasal cavities open into pharynx
Located posterior to the nose, extends to the soft palate
Includes the eustachian tubes (maintain pressure in the middle ear) and the pharyngeal tonsils which are located on the posterior wall just above the oropharynx - tonsils are part of the lymp system and help defend against bacteria.
Where the oral cavity opens into the pharynx, between the soft palate and the hyoid bone, just behind the tongue.
What is included in the oropharynx?
Palatine tonsils, which are between the two arches of tissue to the sides of the opening into the pharynx form the mouth (most often removed in a tonsillectomy) and lingual tonsils, which are located at the base of the tongue
- Both are also parth of the lymp system and protect against bacteria.
Opens into the larynx and is between the hyoid bone and the esophagus
Passageway for air from the nose or mouth to the larynx and for food from the mouth to the esophagus.
Formed from thyroid (larger, superior) and cricoid (inferior) cartilage
The voice box (sound production)
Directs food into esophagus and air into trachea
Opening into the larynx
Cartilaginous flap that covers the glottis when swallowing food.
What can be found at the anterior end of the glottis?
At the anterior end of the glottis, the mucous membrane of the larynx forms 2 pairs of folds:
- One pair, the false vocal cords, form the wall of the glottis
- The second pair are the true voval cords, which vibrate to produce sound.
What are the five divisions/structures of lower respiratory tract?
- Trachea (windpipe)
- Primary bonchi
Extends from larynx to bronchi
Made of C-shaped cartilagnious rings that prevent it from collapsing.
What lines the trachea/windpipe?
Lined with ciliated mucous membrane
- The cilia beat upward to push and bits of food and out into the pharynx where is can be swallowed or coughed out.
2 branches off the trachea, one to each lung - enter at the hilum.
The right branch is shorter and wider, so inhaled objects usually enter the right bronchus.
The bronchi branch into smaller tubes called secondary bronchi and these branch into tertiary bronchi
Many smaller tubes branching off from tertiary bronchi - final branches are the terminal bronchioles.
What composes the bronchioles?
Do not have cartilage, but are made of smooth muscle; if the smooth muscle contracts, the airways become narrow.
What exactly is an asthma attack?
If all the broncioles contract at the same time, the person has an asthma attack.
Clusters of sacs at the end of the terminal bronchioles (alveolar ducs lead to alveolar sacs).
Site of gas exchange
Why is gas exchange allowed to occur at the alveoli?
Pulmonary capillaries surround the alveoli
Membranes of the capillaries and the alveoli are very thin, which allows oxygen to pass from the alveoli into the capillaries and carbon dioxide to pass from capillaries into alveoli
The two membranes (alveolar and capillary) collectly are called the respiratory membrane.
A disease characterized by the alveoli becoming brittle and eventually rupturing.
What lines the alveoli?
Lined with mucous, which is high in water content.
What is dangerous about the high water content of the mucous?
Water molecules are cohesive and attract each other (have high surfce tension), which can cause the walls of the alveoli to collapse.
How do we counter this high water tension in the alveoli?
Specialized cells in the alveoli produce surfactant to break the surface tension and allow the alveoli to remain open.
What happens to the surfactant producing cells in premature babies?
In premature babies, the surfactant-producing cells are underdeveloped and the alveoli collapse
This causes IRDS (Infant Respiratory Distress Syndrome), which is the leading cause of death of premature babies in the U.S.
2 cone-shaped organs extending from slighly above the clavicles to the diaphragm and within the rib cage
The bronchi, bronchioles, and alveoli are all within the lungs
What are the divisions of the left lung?
The left lung is divided into two lobes, superior and inferior, separated by oblique fissure.
What are the divisions of the right lung?
The right lung is divided into three lobes, superior and middle are separated by the horizontal fissure, and middle and inferior are separated by the oblique fissure.
What are the structures on the surfaces of the lungs?
- Cardiac Notch (on left, for heart)
- Costal Surface (along ribs)
- Mediastinal Surface (containing the hilus)
What are the cavities in which the lung is located and lined by?
Located within the pleural cavity
The thoracic wall forms the cavity, which is lined with the parietal pleura membrane
The lungs are enclosed in the visceral pleura.
A dome-shaped muslce that forms the thoracic cavity floor within which the lungs are found.
The movement of air into and out of the lungs
Normal, good, unlabored breathing, sometimes known as quiet breathing or resting respiratory rate.
- Diaphramatic Breathing
- Costal Breathing
Deep breathing, is breathing that is done by contracting the diaphragm
Air enters the lungs and the chest rises and the belly expands during this type of breathing.
Method that uses movements of the ribs to drive both the inhale and the exhale phases of your breath.
- External Intercostal Muscles
- Internal Intercostal Muscles
Increased depth and rate of breathing.
The diaphragm contracts, which pulls it downward, while the external intercostals pull the ribs up, increasing the volume of the thoracic cavity.
This causes the lung volume to increase and lowers the air pressure in the lungs, which causes a partial vacuum, pulling air in.
The process of breathe out in a deliberate manner.
The diaphragm and the external intercostals relax, decreasing the volume of the thoracic and the lungs and increasing the air pressure in the lungs, causing the air to be pushed out.
Contraction of abdominal muscles and the internal intercostals forcing the diaphragm up and the ribs inward, causing more pressure in the lungs and thoracic cavity, thus forcing more air out.
Located in the medulla oblongata
Sends impulses to the diaphragm and intercostal muscles.
Used to measure respiratory function
Tidal Volume (TV)
The lung volume representing the normal volume of air displaced between normal inhalation and exhalation when extra effort is not applied.
Average: about 500 mL
Vital Capacity (VC)
The greatest volume of air that can be expelled from the lungs after taking the deepest possible breath.
Average: about 4500 - 5000 mL
Inspiratory Reserve Volume (IRV)
The maximal amount of additional air that can be drawn into the lungs by determined effort after normal inspiration
Average: about 3100 mL
Expiratory Reserve Volume (ERV)
The additional amount of air that can be expired from the lungs by determined effort after normal expiration.
Average: about 1400 mL
Residual Volume (RV)
The volume of air still remaining in the lungs after the most forcible expiration possible.
Average: about 1000 mL
Total Lung Capacity
Simply, your vital capacity plus the residual volume.
Common Cold (Respiratory Infection)
Caused by a virus that enters the cells of the upper respiratory tract; spread by mucous droplets containing the virus.
What are the symptoms and the usualy temporal occurances of the common cold?
Symptoms - nasal stuffiness, scratchy throat, headache, sneezing, and coughing.
More than 150 cold viruses
Usually occurs in winter because people are confined and are in close contact with one another.
Influenza (Respiratory Infections)
A virus enters respiratory cells, kills them, and causes inflammation and irritation in the trachea and bronchi.
Symptoms - fever, coughing, shortness of breathing, and pharyngeal pain.
Bronchitis (Respiratory Infection)
Viral or bacterial infection
Acute -usually bacterial, responds to antibiotics.
Symptoms - heavy mucous discharge, persistent cough
Chronic - caused by infection or the environment (ex. smoking).
Strep Throat (Respiratory Infections)
Caused by bacteria
Symptoms - fever, sore throat
If not treated, can lead to rheumatic fever.
Compromised airflow during "attacks" due to inflammation, mucous secretion, and bronchoconstriction.
Symptoms - wheezing, shortness of breath
Causes - exercises, allergens (hyper-responsiveness)
Treatment - inhalers (bronchodilators and/or steroid)
Pneumonia (Lung Disorders)
Can be bacterial or viral
Fluid builds up in the alveoli
Can cause death
Tuberculosis (Lung Disorders)
Caused by a bacterium
Bacteria form a tubercle (specific infected site)
When the tubercle breaks apart, bacteria spread and form calcified centers that can be detected on x-rays.
Pulmonary Fibrosis (Lung Disorders)
Environmental particles (contaminants) are inhaled
Causes: asbestos, silica, coal dust
Causes cells in the lungs to form fibrous CT, making the lungs less elastic and therefore less efficient.
Lung Cancer (Lung Disorders)
Cells exposed to irritants such as cigarette smoke lose control over cell division
Cells divide, forming a mass called a callus
When the cells develop abnormal nuclei, there are labeled "cancer".
What happens if the cells break way from callus?
If the cells break away from the callus and circulate to ther parts of the body or lungs, they are metastasizing (and are called metastasis).
What can be done if cancer remains in the lung?
If the cancer reamins in the lung, the lobe can removed via a procedure callaed a pneumonectomy.
What is the role of mucous in the lungs?
Mucous covers the epithelium of the respiratory system. This mucous helps eliminate dust and pollen, traps particles, etc. to help clean the air we take in.
What does smoking do in the lungs?
Tobacco smoke irritates the epithelial cells and destroys macrophages (small cells that kill bacteria). This allows toxins to reach the lungs' alveoli.
The frequent coughing of smokers is the respiratory system's attempt to clean itself.
What are the statistics for smokers?
Of all cases of lung cancer, 90% are caused by smoking.
Nearly 500,000 people die each year from smoking.
The life expectancy of a smoker is 13 - 14 years less than that of a nonsmoker.
What happens to nonsmokers who exposed to smoke?
Nonsmokers exposed to cigarette smoke are at risk, and children exposed to cigarette smoke have an increased rate of asthma, bronchitis, and pneumonia.