Lesson 17: Respiratory System

what are the 6 functions of the respiratory system

1. pulmonary ventilation (breathing)

2. gas exchange (external respiration)

3. gas conditioning (warm, humidify, and cleanse air)

4. sound production

5. olfaction

6. defense

what are the 5 functions of the nasal cavity

1. airway for respiration

2. warm, humidify and clean inhaled air

3. resonating chamber for speech and sound

4. houses olfactory receptors

5. pseudostratified cilited columnar epithelium- protection

what is apart of the upper respiratory tract?

sphenoidal sinus, frontal sinus, nasal cavity, pharynx

what is apart of the lower respiratory tract?

larynx, trachea, bronchi, lungs

features and functions of the nasal cavity

• airway for respiration

• warm, humidify, and clean inhaled air

• resonating chamber for speach and sound

• houses olfactory receptors

• tissue- pseudostratified ciliated columnar epithelium

CONTAINS:

• ethmoidal sinuses

• superior, middle, and inferior nasal concha

• hard palate

• tongue

• oral cavity

• sphenoidal sinus

• superior, middle, and inferior meatus

• nasopharynx

• uvula

features and functions of the pharynx

throat

connects nasal cavity and mouth to larynx and esophagus

3 regions-

• nasopharynx- pseudostratified ciliated columnar

• oropharynx- stratified squamous

• laryngopharyx- stratifix squamous

features and functions of the larynx

voice box

provides open airway

CONTAINS:

• epiglottis- routes air and food

• vestibular folds- false vocal cords, doesn’t produce sound

• vocal folds- true vocal cords, produce sound

• thyroid cartilage

• ciricoid cartilage

• arytenoid cartilage

features and functions of the trachea

“c” shaped hyaline cartilage rings

posterior wall is not rigid, but muscular

tissue- pseudo stratified ciliated columnar

mucus producing goblet cells

features and functions of the bronchial tree

primary bronchi

secondary (lobar) bronchi

• 2 left, 3 right

tertiary (segmental) bronchi

• 8-10 left, 10 right

9-12 more bronchial divisions

bronchioles- microscopic

• no longer contain cartilage

• smooth muscle (bronchioconsteriction or bronchodilation)

describe the structure and function of lung alveoli

CONTAINS:

branch of pulmonary artery

alveolar duct

alveoli

connective tissue

capillary beds

branch of pulmonary vein

respiratory bronchiole

terminal bronchiole

bronchiole

Alveolar cell types (6)

alveolar macrophages (dust cells)

alveolar cell type II cells (secrete surfactant)

alveolar type 1 cells (simple squamous)

erythrocyte

pulmonary capillaries

alveolar pore

gross anatomy of lungs

gross anatomy of pleurae

pulmonary ventilation- inspiration or inhalation

Diaphragm contracts

external intercostals, scalenes and others contract

How it works:

• volume of thoracic cavity increases

• internal lung pressure decreases, air rushes into lungs

pulmonary ventilation- expiration or exhalation

Diaphragm passively relaxes (lung elastic recoil)

abdominal wall, internal intercostals and others contract

How it works:

• volume of thoracic cavity decreases

• internal lung pressure increases

• air rushes out of the lungs

external respiration

gas exchange between blood and air (at alveoli)

• O2 diffuses air to blood

• CO2 diffuses from blood to air

internal respiration

gases exchange between blood and tissue cells (at systemic capillaries)

• O2 diffuses into body cells;

• (O2 diffuses from body cells into blood)

cystic fibrosis

genetic disease

cells cannot secrete chloride

AFFECTS:

organs that secrete mucin, tears, sweat, digestive juices, saliva

RESULTS:

thick, sticky mucus

TREATMENTS:

antibiotics, orally administered pancreatic enzymes, caloric supplements

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mucus obstructs resp. passageways and ducts of clands such as pancreatic ducts and prevents digestive enzymes from entering small intestine

Asthma

hypersensitivity leads to inflammation and bronchoconstriction

— may occur in response to pollen, smoke, mold, dust, mites, exercise anxiety

SYMPTOMS:

wheezing, coughing, shortness of breath, excess mucous

TREATMENT:

inhaled steroids mixed w/ bronchoconstriction

Emphysema

chronic destruction of alveoli and loss of lung elastic tissue

decrease in gas exchange surface area

loss of elastic tissue makes it difficult to exhale; old air trapped in alveoli

usually caused by smoking

pneumonia

infection of the alveoli of the lungs resulting in swelling and reduced capacity for gas exchange

CAUSE:

viruses, bacteria or fungi

SYMPTOMS:

cough, fever, rapid breathing, sputum

Lung cancer

usually caused by cigarette smoking

3 TYPES:

1. squamous cell carcinoma (most common)

2. adenocarcinoma

3. small cell carcinoma

TREATMENT (most effective)

• complete removal of diseased lung

what is the development of the respiratory system weeks 4-6

week 4- respiratory diverticulum and primary bronchial buds form off of endoidermal tube

week 5- secondary bronchial buds form

week 6- teritary bronchi form

why do we have c-shapes cartilage in our trachea

when we swallow big things (pills, food), c-shape allows to expand into the area that the trachea has

what do goblet cells produce

goblet cells produce mucus

the hilum includes what things?

primary bronchi, pulmonary veins, pulmonary arteries

how are bronchioles different than bronchi

bronchioles aren’t made of cartilage

what happens within alveoli

where gas exchange happens

why does Alveolar type 1 cells need to be simple squamous

so it can be thin enough that O2 and CO2 can pass through

what is surfactant

prevent alveoli from collapsing

why do we have dust cells

to get rid of dust and stop problems from happening