Respiratory System
Internal and External Respiration
Major Functions
Anatomy of Respiratory Tract
Breathing Mechanism
Definitions of Lung Capacity Terminology
Disorders of Respiratory System
Organs of Respiratory System
Differences between right and left lung and right and left primary bronchi
Gas exchanges between blood and external environment
Passageways to lungs purify, warm, and humidify incoming air
Upper Respiratory Tract
Lower Respiratory Tract
Sinuses
Pharynx
Nasal Cavity
Nose
Larynx
Trachea
Bronchial Tree
Lungs
Internal: flow of air into lung
External: air leaving lung
Ribs rise
Muscles contract
Forced Inhalation: scalenes muscles, sternocleidomastoid, and pectoralis minor
Lungs fill
Diaphragm moves down
Passive Process: diaphragm and rib muscles relax
Forced Expiration: contraction of intercostal (ribs) muscles and abdominal muscles
Lungs decrease in size with contracting ribcage
Ribs move down and inwards
Diaphragm moves up
Functional Residual Capacity: residual volume + expiratory reserve volume
Vital Capacity: inspiratory reserve volume + tidal volume + expiratory reserve volume
Inspirational Capacity: tidal volume + inspiratory reserve volume
Total Lung Capacity: sum of all volumes
Apnea: termporary cessation
Dyspnea: painful or labored breathing
Eupnea: normal and quiet
Tachypnea: rapid breathing
Sudden Infant Death Syndrome (SIDS)
Asthma
Lung Cancer
Birth Defects
Chronic Bronchitis
Emphesyma
Chronic Obstructive Pulmonary Disease
Labored or difficulty (dyspnea) becomes progressively more severe
Coughing and frequent pulmonary infections are common
Major causes of the US
Hypoxic (insufficient oxygen in tissues)
Patients almost always have a smoking history
Leads to respiratory failure
Airways collapse during expiration
Patients use a large amount of energy to exhale
Chronic inflammation promotes lung fibrosis
Overflation causes barrel chest
Alveoli enlarge as adjacent chambers break through
Cyanosis (blue skin due to lack of oxygen in blood and tissue) late in disease
Mucosa becomes inflamed
Pnuemonia is common
Mucus production increases
Pooled mucus impairs ventilation and gas exchange
Risks of lung infection increases
Associated with smoking
Three common types
1/3 of cancer deaths in US
adenocarcinoma
small cell carcinoma
squamous cell carcinoma
Unexplained infant death
Causes maybe due to neural respiratory control center or abnormal heart rhythms
Chronic inflamed hypersensitive bronchiole passages
Responds to irritants with dyspnea, coughing, and wheezing
cystic fibrosis: oversecretion of thick mucus clogs the respiratory system
Lungs
Primary Bronchi
Right
Left
Right
Left
3 fissures
2 fissures
wider
shorter
straighter
longer due to presence of heart
Trachea (windpipe)
Primary Bronchi
Lungs
Fairly rigid because of the C-shape rings made of hyaline cartilage to keep airway open at all times
Ciliated mucosa is beat by continuously opposite direction of incoming air
Lined with ciliated mucosa
Mucus loaded with dust and other debris away from lungs
Connects larynx to bronchi
Right bronchus is wider, short, and straighter than the left, due to the presence of the heart on the left side
Bronchi subdivide into smaller and smaller branches
Formed by division of trachea
Enters the lung at hilus
Apex is clavicle (superior portion)
Base rest on diaphragm (inferior portion)
Occupy most of thoracic cavity
Each lung is divided into lobes by fissures (2: left, 3: right)
Nasal cavity:
Paranasal Sinuses
Nose
Pharynx (throat)
Air enters nose through external nares (nostrils)
Nasal cavity (interior of nose) divided by nasal septum
Rest lined with respiratory mucosa
Cateral walls have conchae
increases surface area
increases air turbulence within nasal cavity
Olfactory receptors (sense of smell) located in mucosa on superior surface
Traps incoming foreign particles
Moistens air
Cavities within bones:
frontal, sphenoid ethmoid, maxillary bone
lighten the skull
resonance chambers for speech
produce mucus
muscular passage from nasal cavity to larynx
three regions:
nasopharynx: superior region behind nasal cavity (passage of air only)
oropharynx: middle region behind mouth
laryngopharynx: inferior region attached to larynx
oropharynx and laryngopharynx are common passageways for air and food