Respiratory System

Upper respiratory tract

includes

• nasal cavity

• oral cavity

• pharynx

function: filters, warms and humidifies air

Lower Respiratory Tract

includes:

• larynx

• trachea

• bronchi

• lungs

function: transport and exchange of gases

Conducting Portion

Includes:

• Nasal cavity
  • Oral cavity
  • Pharynx
  • Larynx
  • Trachea
  • Bronchi
  • Bronchioles
  • Terminal bronchioles

Function: filters, warms and humidifies air

Respiratory Portion

Includes:

• • Respiratory bronchioles
  • Alveolar ducts
  • Alveolar sacs
  • Alveoli

Function: gas exchange

respiratory system cell type

pseudostratified ciliated columnar epithelium

External Nares (nostrils)

blue

allows air to enter and exit system

Internal Nares (choanae)

yellow

allow air to pass from nasal cavity to throat

hard palate

pink

• interior, boney, roof of mouth

• rigid structure

• allows for speech, and food manipulation,

• separates oral and nasal cavities

soft palate

green

• posterior, muscular, flexible

• closes nasal cavity during swallowing and speech

nasal cavity

pink

Function: conditions inhaled air by warming, moisterizing, and filtering it

Nasal Chochae

green

function: produce turbulence
• Fluctuates, moves around
• Increases the length of time air stays in the nasal cavity
• Helps warm and humidify air

Nasal septum

black

provides structural support to nose

Pharynx

• tube for food and air

• contains skeletal muscle

• lined with mucosa

Nasopharynx

black

serves as airway and regulates pressure

Oropharynx

Green

pathway for food and air

Laryngopharynx

blue

protects airway and redirects food to esophagus

Opening of auditory tube

yellow

connects ear to nasopharynx

Lingual Tonsil

blue

filter pathogens passing through mouth

Palatine Tonsil

black

first line of defense against inhaled pathogens

larynx

functions: breathing, phonation (producing sound), protection of respiratory system

hyoid bone

red

functions: enable swallowing, enable speech, secure airway and support tounge movement

epiglottis

yellow

function: sorts food and air by closing airway when swallowing and esuring food and liquid go to esophagus and not lungs

Thyroid Cartilage

Green

function: protects vocal cords

cricoid cartilage

black

function: keeps airway open and serves as an attachment point for other muscles and ligaments

Arytenoid Cartilage

pink

controls movement of vocal cords

ventricular fold

yellow

allow for coughing and gagging, along with protecting airway while swallowing

vocal fold

green

phonation and airway protection

Rema Glottides

blue

narrows and widens to regulate airflow and produce sound

trachea

“windpipe”

allows air to travel in and out of lungs

tracheal cartilage

provide trachea support and flexibility

bronchial tree

airway system conducting air between the trachea and the lungs

primary bronchi

green

largest tubes, main entry point for air from trachea

secondary bronchi

blue

deliver and separate air into different lobes

segmental bronchi

yellow

branch from secondary bronchi - distribute air to different, independant sections called bronchopulmonary segments

smaller bronchi

red

narrower branches of segmental bronchi - regulate air distribution through contraction and relaxation

bronchioles

conduct air between bronchi and alveoli

regulate airflow through contraction and dilation

Terminal bronchioles

deliver air to respiratory bronchioles (where gas exchange begins)

Bronchi vs bronchioles

bronchi-

• incomplete rings of cartilage

• psuedostratified ciliated columnar epithelium

Bronchioles:

• no cartilage

• simple columnar/cuboidal epithelium

resiratory bronchioles

blue

conduct air and initiate gas exchange

alveolar ducts

pink

connect respiratory bronchioles to alveolar sacd

alveolar sacs

yellow

primary location for gas exchange

alveoli

functional units of lung tissue
• Gas exchange location between air and blood

type 1 alveoli

simple squamous epithelium. Rapid gas diffusion

type 2 alveoli

secrete fluid to reduce surface tension and prevent alveoli collapse

Alveolar Macrophanges

clear airspaces. Fixed or free

visceral pleura

green

directly covers lungs

parietal pleura

blue

lines inner chest wall

lung

gas exchange

superior lobe

provide air to upper portion of lungs

middle lobe

provide air to medial portion of lungs

inferior lobe

provide most air - lower portion of lungs

oblique fissure

blue

separates lung lobes

Transverse fissure

green

separates lung lobes

bronchopulmonary segments

Supplied by a single segmental bronchus, branch of a pulmonary
artery, and branch of a pulmonary vein

pulmonary circulation

• Transportation of deoxygenated blood from the heart (right side) to the lungs
• Returns oxygenated blood to the heart (left side)

Bronchial Circulation

Part of the systemic circulation
• Smaller than the pulmonary circulatory system
• Supplies the alveolar cells
• Bronchial arteries and veins supply the bronchi and bronchioles
• Arteries: Thoracic aorta à capillary beds à bronchial tree
• Veins: drain into the azygos/hemiazygous systems

Pulmonary ventilation

“quiet” breathing

quiet breathing

• Diaphragm
• External intercostals
Moves air in and out of lungs

forced inhalation

Accessory muscles:
• Sternocleidomastoid
• Pectoralis minor
• Erector spinae
Increases thoracic cavity volume

forced exhalation

• Internal intercostals
• Abdominal muscles
Decreases thoracic cavity volume