Respiratory System

what are the basic functions?

supply body with oxygen

dispose of carbon dioxide

what are the 4 processes involved in respiration?

1. pulmonary ventilation

2. external respiration

3. trasnport of respiratory gases

4. internal respiration

what is pulmonary ventilation?

involves two processes:

inhalation (inspiration) - draw gas into lungs

exhalation (expiration) - force gas out of lungs

what is external respiration?

the exchange of gasses with the outside environment

what is internal respiration?

the exchange of gases with the tissues

so at tissue level - blood vessels - cells

what are the respiratory organs?

1. nose and nasal cavity

2. pharynx, larynx, and trachea

3. bronchi and smaller branches

4. lungs and alveoli

what are the two divisions of the respiratory system?

conducting zone and respiratory zone

what is the conducting zone?

• passageway that conveys air

• filters, humidifies, and warms incoming air

what is the respiratory zone?

• site of gas exchange in the lungs

• includes the alveoli structures

what is the funcion of the nose?

• airway that moistens and warms air

• hair filters the air

• resonating chamber of speech

• houses olfactory receptors

what makes the size of the nose?

nasal cartilage

what filters the air in the nose?

the hairs

what are the external nares?

the nostrils

what divides the nostrils?

the nasal septum

what is the nasal cavity continous with?

the nasopharynx

what are the posterior apertures in the nasal cavity?

the choanae

what are the two types of mucous membranes?

olfactory mucosa and respiratory mucosa

where is the olfactory mucosa found?

near the roof of nasal cavity and it houses olfactory receptors

where is the respiratory mucosa?

it lines the nasal cavity

what does the respiratory mucosa consist of?

• pesudostratified ciliated(fingerlike that moves the mucus) columnar epithelium

• goblet cells

• lamina propia

where does the cilia move the contaminated mucus?

posteriorly to the pharynx

• filtered particles and mucus are swallowed and eventually digested by the juices in the stomach

what is the pharynx?

• funnel shaped passageway tahat connects the nasal cavity & mouth

what are the 3 main divisions of the pharynx?

1. nasopharynx

2. oropharynx

3. laryngopharynx

what is an important characteristic about the type of mucosal lining?

THE TYPE OF MUCOSAL LINING CHANGES ALONG ITS LENGHT

what does the pharynx allow?

• air and food to pass

• swallowing

• vocalization

• immunological role

where is the nasopharynx?

• superior to the point where the food enters

• ONLY AN AIR PASSAGEWAY

what happens to the pharynx during swallowing?

it gets closed off

• UVULA reflects superiorly

what are pharyngeal tonsils and functions?

• adenoids

• located on posterior wall

• destroy entering pathogens

what tube does the nasopharynx contain?

pharyngotympanic tube (auditory tube)

what do tubal tonsils provide?

protection from infection

what is the oropharynx?

entranceway that extends from soft palate to the epiglottis

what are the fauces?

archlike entranceway in the oropharynx

what are teh two types of tonsils in the oropharynx?

palative and lingual

where is the palative tonsil?

in the lateral walls of the fauces

where is the lingual tonsil?

cover tthe posterior surface of the tongue

what is the laryngopharynx?

passageway for both food and air

where does the laryngopharynx extend to?

extends to inferior boundary of cricoid cartilage

what are the continous phases of the pharynxs.

the nasopharynx is continous with the nasal cavity

then comes the oropharynx which is continous with the laryngopharynx

laryngopharynx is continuos with the esophagus and the larynx.

what deos the larynx involve?

thyroid cartilage

epiglottis

vocal ligaments

rima glottidis

glottis

what is thyroid cartilage?

shield-shaped that forms the laryngeal prominence (adams apple)

what are the 3 pairs of small cartilages found in the larynx?

arytenoid

corniculate

cuneiform

what is the epiglottis?

structure that tips inferiorly during swallowing

what are the two vocal ligaments of the larynx?

vocal folds and vestibular folds

what are the vocal folds?

folds that act in sound

true vocal cords

what are the vestibular folds?

folds that have no role in sound production and only provide support for the vocal cords

false vocal cords

where is the larynx found?

it extends from the 4th to 6th cervical vertebrae

• attaches to hyoid bone superiorly

what does the larynx open to?

into the laryngopharynx

what is the larynx continous with?

inferiorly continous with the trachea

what are the 3 functions of the larynx?

voice production

provide an open airway

route air and food into the proper channels

superior opening of the larynx are?

closed during swallowing

open during breathing

what is the framework of larynx?

arrangement of nine cartilages

voice production: Length of cords?

changes with pitch

voice production: loudness?

depends on force of air

what is Valsava’s maneuver?

straining

sphincter function of the larynx

innervation of the larynx?

recurrent laryngeal nerves (branch of vagus)

what is the trachea?

• descends into the mediastinum

• C-shaped cartilage rings that keep airway open

what is trachealis?

located between open ends of c shaped cartilage rings along lenght of posterior trachea

• if it gets smaller its harder to breathe

what is carina?

marks where trachea divides into 2 primary bronchi

what is bronchial tree?

extensively branching respiratory passageways

what is primary bronchi? ( main bronchi)

largest bronchi

what is right main bronchi?

wider and shorter than left bronchi

what are the secondary LOBAR bronchi?

3 on the right

2 on the left

what are the tertiary (segmental) bronchi?

they branch into each lung segment

what are bronchioles?

little bronchi, less than 1 mm in diameter

what are terminal bronchioles?

less tham 0.5mm in diameter

supportive connective tissue changes?

the c shaped rings are replaced by cartilage plates

epithelium changes?

pseudostratified ciliated columnar is replaced by simple columnar, then simple cuboidal

does smooth muscle become important in changes in tissue composition?

yes

airways widen with?

sympathetic stimulation

airways constrict under?

parasympathetic stimulation

structure in the respiratory zone?

respiratory bronchioles

• gas exchange occurs where smooth muscle is absent

• branch from terminal bronchioles

• lead to alveolar ducts

• lead to alveolar sacs

what is alveoli?

400 million for surface area for gas exchange

alveolar and capillary walls plus their basal lamina form?

respiratory membrane

what do the alveolar macrophages do?

tehy remove the tiny inhaled particles and migrate into bronchi

steps of the bronchial tree?

primary bronchi (2)

secondary bronchi (2)

tertiary bronchi (8/10)

bronchioles ——- terminal bronchioles

respiratory bronchioles

alveolar ducts

alveoli

what does conducting portion include?

primary bronchi (2)

secondary bronchi (2)

tertiary bronchi (8/10)

bronchioles ——- terminal bronchioles

what does respiratory portion include?

respiratory bronchioles

alveolar ducts

alveoli

what are the major landmarks of the lung?

1. apex- superior tip of lung

2. base- concave inferior surface

3. hilum- indentation on mediastina

4. root- the structure that enter and leave the lung at the hilum

what is the hilum?

the region where blood vessels, bronchi, and nerves enter and exit the lung

gross anatomy of left lung?

• superior and inferior lobes

• fissure- oblique

• cardiac notch- the depression that accomodates the heart

gross anatomy of the right lung?

• superior, medial, and inferior lobes

• fissures- oblique and horizontal

what do pulmonary arteries do?

deliver oxygen poor blood into the lungs

what do pulmonary veins do?

carry oxygenated blood to the heart

innervation of lungs involves?

sympathetic, parasympathetic, and visceral sensory fibers

parasympathetic lung innevation?

bronchoconstriction and vasodilation

sympathetic lung innevation?

bronchodilation and vasoconstriction

what is the pleurae?

a double layered sac surrounding each lung

it involves:

• parietal pleura- towards the cavity wall

• visceral pleura- on top of the organ

what is the pleural cavity?

potential space between the visceral and parietal pleurae

what does the pleurae divide?

the thoracic cavity

• central mediastinum

• two lateral pleural compartments

what is mechanism of ventilation?

process of supplying oxygen and disposing carbon dioxide

required for mechanism of ventilation?

• pulmonary ventilation

• external respiration- between lung and blood

• transport of respiratory gases

• internal respiration- between blood and tissue

alveolar ventilation?

movement of air into and out of the alveoli (gas exchange site)

ventilation is accomplished by?

the cation of the respiratory muscles

two phases of pulmonary ventilation?

inspiration - inhalation

expiration - exhalation

in inhalation?

• volume of thoracic cavity increases

• diaphram flattens

• intercostal muscles contract to raise the ribs

• decreases internal gas pressure

deep inspiration requires?

• scalenes

• sternocleidomastoid

• pectoralis minor

• quadratus lumborum

• erector spinae

during exhalation?

• passive process

• inspiratory muscles relax

• diaphragm moves up

• volume of thoracic cavity decreases

forced expiration?

• active process

• contraction of internal and external oblique muscles

• transversus abdominis muscle

what is the most important respiratory center?

VRG- ventral respiratory group

• locateed in reticular formation in the medulla oblongata

• neurons generate respiratory rhythm

what are chemoreceptors?

sensitive to oxygen and carbon dioxide

• sensitive to rising and falling oxygen levels