Respiratory System

Bianca J. MassonDevonna WilliamsRihannon Suarez

VIDEOhttp://youtu.be/RPdGQ-A_yM4

Functions of the Respiratory System• The primary function of the respiratory system is gas

exchange– Inhale, breathing in O2 (INSPIRATION)– Exhale, breathing out CO2 (EXPIRATION)

OTHER FUNCTIONS…1. Pulmonary ventilation= entrance and exit of air in lungs2. External respiration=exchange of oxygen and carbon dioxide between air and blood3. Internal respiration=exchange of gases between blood and tissue fluids4. Transport of gases to and from the lungs and the tissues

These four allow cellular

respiration to continue.

Pag

e 3

01

The Respiratory Tract

• Traces the path of air from the nose to the lungs.

• Cleansing of air is accomplished by cilia and mucus in the nasal cavities.

• In the nose, the cilia carry mucus, dust, and occasional bits of food that “went down the wrong way” into the pharynx.

• The air is warmed by heat given off by the blood vessels lying close to the surface of the lining of the airways, and it is moistened by the wet surface of these passages.

• The air still retains so much moisture, however, that upon expiration on a cold day, it condenses and forms a small cloud.

Upper Respiratory Tract

Nasal Cavities• Hollow spaces in nose,

that filters, warms and moistens air.

Pharynx• In chamber posterior to

oral cavity, connects to surrounding regions.

Glottis• Opening into larynx

functions as passage of air into larynx.

• Cartilaginous organ that houses the vocal cords; voice box for sound production.

Larynx

Pag

e 3

02

Lower Respiratory Tract

Trachea• Flexible tube that connects

larynx with bronchi as a passage of air.

Bronchi• Paired tubes inferior to the

trachea that enters the lungs which serve as a passage of air to lungs.

Bronchioles• Branched tubes that lead

from bronchi to alveoli which serves as a passage of air to each alveolus.

• Soft, cone shaped organs that occupy lateral portions of thoracic cavity that are used for gas exchange and acid-base balance.

Lungs

Pag

e 3

02

Lower Respiratory TractCONTINUED…

Alveoli• Air sacs that branch from

bronchioles and functions as passage of gases into and out of pulmonary capillaries.

Pulmonary Capillaries• Capillaries that cover

surface of alveoli and that receive oxygen from alveoli; oxygenation of hemoglobin; deliver carbon dioxide from tissues to alveoli.

Pag

e 3

02

The Nose• The nose is the only external portion of

the respiratory system.• Air enters the nose through external

openings called nostrils. • The nose contains two nasal

cavities, which are narrow canals separated from one another by a septum composed of bone and cartilage.

• Mucous membrane lines the nasal cavities.

• The nasal conchae increase the surface area for moistening and warming air during inhalation and trapping water droplets during exhalation.

• Odor receptors are on the cilia of cells.• The tear (lacrimal) glands drain into the

nasal cavities by way of tear ducts. For this reason, crying produces a runny nose.

• Paranasal sinuses act as resonating chambers for the voice.

Pag

e 3

02

• The pharynx, commonly referred to as the “throat,” has three parts: the nasopharynx, for air only the oropharynx, where the oral cavity joins the pharynx; and the laryngopharynx, which opens into the larynx. 

• The nasal cavities, which filters, warm and humidify incoming air, open into the pharynx.

• The food and air passages cross in the pharynx, which conducts air to the larynx and food to the esophagus.

The Larynx• The larynx is a cartilaginous

passageway for air between the pharynx and trachea.

• Called the voice box because it houses vocal cords, which slit between the cords through the glottis.

The Pharynx

Pag

e 3

02

-3

Section 2P

age

30

6

Mechanism of Breathing

Mechanism of Breathing• Ventilation is the way air enters and exits the lungs

• Conditions of the lungs: *lie within the sealed-off thoracic cavity *they adhere to the thoracic wall by the way of the pleurae * continuous column of air extends

• Inspiration- the active phase of ventilation where the diaphragm and the external intercostal muscles contract.

• Expiration- the passive phase of ventilation, where diaphragm and external intercostal muscles relax.

• Tidal volume – the small amount of the air that moves in and out with each breath when one is relaxed.

• Vital Capacity- the maximum amount of air a person can exhale after taking the deepest breath.*Vital Capacity may vary by how much we can increase inspiration and expiration over the tidal volume amount.

Pag

e 3

06

Control Of VentilationAdults have a breathing rate of

12 to 20 ventilations per minuteThe rhythm of ventilation is

controlled by the primary respiratory center

Primary Respiratory center is located in the medulla

oblongata.The primary respiratory center automatically sends out motor nerve signals by the way of the

phrenic nerve to the diaphragm.

Pag

e 3

08

EmphysemaLungs W/ Emphysema

• Caused by continuous cigarette smoking

• Respiratory membranes breaks down, alveoli but they are enlarged.

• Medical treatment is limited to drugs that can dilate the bronchi and bronchioles by relaxing the smooth muscle, along with inhaled oxygen

• Surgical options for people with end stage Emphysema:

*lung volume reduction surgery *lung transplant • Prior to surgery ,they must undergo

rehabilitation where they have to quit smoking forever.

• Lung volume reduction surgery is a very dangerous procedure and not a cure for emphysema .

• Improvements is oxygenation of the blood, tolerance for exercise, and overall lung function enable some patients to return to their normal lives.

Section 3Gas Exchange and

TransportPag

e 3

01

External Respiration

• External respiration- exchange of gases in the lung.

• Gases are exchange between air in the alveoli & blood in the pulmonary capillaries.

• Blood is dark when entering pulmonary capillaries due to low O2.

• After inspiration, the oxygen in alveoli has more oxygen than the blood entering the lungs. O2 for the alveoli then diffuses in the blood.

Pag

e 3

11

Internal Respiration• Internal respiration- exchange of gases in

tissues.• Gases are exchange between the blood in

synthetic capillaries and tissue fluid.• O2 diffuses from blood to tissues because

tissues are low in oxygen.• Tissues have more CO2 than blood, so CO2 that’s

in the tissues transports into the blood.

Pag

e 3

11

Gas ExchangeOxygen transport

• Most oxygen is transported by hemoglobin-red pigment protein in erythrocytes

• Hb+O2=HbO2• A small amount of

oxygen is transported in solution in the blood plasma

Carbon dioxide transport• Most CO2 is transported as

bicarbonate ions (HCO3)

Pag

e 3

11

MEDICAL FOCUSRespiratory and Nonrespiratory Patterns

• Enupina- pattern of quite breathing• Cheyne-Stokes respiration- alternate periods of

hyperpnoea (deep breathing) and apnea(no breathing).

• Breathing increased when CO2 and H+ are high and O2 is low and decreases when O2 is high and CO2 and H= is low

• Sudden cold stimulus (ex) going to vey cold pool), Severe pain.

Pag

e 3

11

Exte

rnal and

Inte

rnal R

esp

irati

on

Section 4Respiration and Health

Pag

e 3

14

Upper Respiratory Tract Infections• The respiratory track is exposed to the environment.

The quality air around us can affect our health .• The upper respiratory tract consists of : nasal cavities,

pharynx and larynx. • Upper respiratory infections can spread from the nasal

cavities to the sinuses , middle ears and larynx.• Viral infections lead to secondary bacterial infection.• Antibiotics have no effect on viral infections, they are

mostly used to treat most bacterial infections.

Pag

e 3

13

Types of Respiratory Tract Infections

• Strep Throat- • caused by Streptococcus pyogenes• Symptoms includes: sore throat, high fever and white patches on a dark red throat. •Treatment is antibiotics

• Sinusitis- infection in the cranial sinuses Symptoms include: postnasal discharge, facial pains(lower forehead,

cheeks). This can be treated by drainage of the sinuses. Antibiotics is only necessary if the condition results from bacterial

infections. Hot showers and sleeping in an upright position can be helpful.

• Otitis Media - a bacteria in the middle ear Symptoms include: pain, fullness, hearing loss, dizziness and fever. Antibiotics is one from of treatment.

Pag

e 3

13

Types of Respiratory Tract InfectionsCONTINUED…

• Tonsillitis –occurs when the tonsils masses of lymphatic tissue in the pharynx become inflamed and enlarged.

If tonsillitis occur frequently and the enlargement makes breathing difficult the tonsils are removed surgically .

• Laryngitis –inflammation of the larynx with hoarseness leading to being unable to talk in an understandable voice.

Treatment for laryngitis is rest it leaves over time. Persistent hoarseness without presence of an upper

respiratory infection is a warning sign of cancer.

Pag

e 3

13

Lower Respiratory Tract Disorders and Infections

• Lower respiratory tract disorders include infections, restrictive pulmonary disorders and lung cancer . P

age

31

4

Lower Respiratory Infections• Acute Bronchitis – an infection of the primary and secondary

bronchi. Symptoms include: deep cough that has mucus and pus.

• Pneumonia- viral or bacterial infection of the lungs where the bronchi and alveoli is filled with thick fluid . It is most common in elderly , week immune system, and smoking. Symptoms includes: high fever, productive cough, difficulty in breathing, headache and chest pain. Pneumonia may be localized in specific lobules of the lungs. It is caused by a bacterium

• Pulmonary Tuberculosis - caused by the tubercle bacillus which is a type of bacterium. Tubercle bacillus shows no reaction but one who has had or is fighting an infection shows an area of inflammation that peaks in about 48 hours.

Pag

e 3

13

-4

Pulmonary Disorders

• There are two types of pulmonary disorders: a) Restrictive pulmonary disorders – a large amount of air is reduced because the lungs has lost their elasticity b) Obstructive pulmonary disorders - air does not flow freely in the airways, it takes time to inhale or exhale.

• Sand, coal dust, clay, cement, flour and fiber glass leads to pulmonary fibrosis.

• Chronic Bronchitis- obstructive pulmonary disorders. *air ways are flamed and filled with mucus. * changes occur such as : loss of cilia and normal cleansing

action. * caused by smoking cigarettes and cigars

Pag

e 3

14

Pulmonary DisordersCONTINUED…

• Asthma- *disease of the bronchi and bronchioles * symptoms: wheezing , breathless, cough, expectoration of mucus * there is no cure for asthma but there is a treatment *special inhalers ( Ventolin)• Lung Cancer *the first event of lung cancer appears to be thickening and

callusing of the cells lining the primary bronchi * next step is where the cilia is lost which makes it impossible to

prevent dust and dirt from settling in the lungs. * following this cells with atypical nuclei appear I the callused lining * cells break loose and penetrate other tissues

Pag

e 3

15

Tobacco and Health• There is no safe way to smoke, all

forms of tobacco can damage and smoking even a small amount is dangerous.

• Smoking do cause cancer not only lung cancer but cancer in the bladder, kidney, pancreas, stomach and uterine cervix.

• Smoking affect the heart and it increase the risk of heart disease .

• Women who smoke and use birth control pill have an increased risk of stroke and blood clots in the legs.

• Sort term effects of smoking *difficulty with breathing * worsen asthma and

allergies

Pag

e 3

16