Respiratory System

Major Functions

Upper Respiratory structures and functions

Lower Respiratory structures and functions

Layers of the Pleurae

Compare and contrast the mechanism of inspiration and expiration

Volume and Pressure relationships in thoracic cavity

Respiratory volumes and capacities

Internal vs. external respiration

Disorders of the respiratory system

Nasal Cavity

Paranasal Sinuses

Nose

Pharynx

The nose has hair to prevent the entry of particles into the airways

the nose is mostly made up of cartilage and some bone

Nose contains nostrils that allow an entrance for air to get in and out of the body

The nasal septum divides the cavity down the middle

Conchae also warm and filter the incoming air

Nasal Conchae are scroll shaped bones that split the cavity into passageways for air

Serve as chambers for the voice to reverberate in

There are the Maxillary, frontal, ethmoid, and sphenoid

Sinuses open into the nasal cavity

Helps to produce sound for speech

Has three subdivisions: Nasopharynx, Oropharynx, Laryngopharynx

The space behind the oral and nasal cavities

And its passageway for air and food

It contains the Visceral (inner layer) and it is attached to the surface of the lungs

Parietal Outer layer which lines the thoracic cavity

It is a double layered serous membrane

Serous fluid lubes the pleural cavity between the two layers

Trachea (windpipe)

Bronchial tree

Larynx

Lungs

transports air in and out of the trachea

HOUSES THE VOCAL CORDS

an enlargement in the airway, superior to the trachea

Formed by muscles and cartilage that is bound by elastic tissue

Also where the adams apple is found

The harder the air goes through the louder the sounds the chords make

Changing tension of the chords changes the pitch of the sound

Tube that extends downward into the thoracic cavity

Splits into right and left primary bronchi

Inner walls are lined with goblet cells and a mucous membrane

Wall is supported by 20 cartilaginous rings that keep the airway open

Primary bronchi are the first branches off of the trachea and they each lead to a lung, the secondary bronchi each enter a lobe of the lungs

Tertiary bronchi each enter a segment

Bronchioles branch off the segmental bronchi, then comes the terminal bronchioles which still conduct air but dont exchange gas, respiratory bronchioles contain alveoli and come off of the terminal

Consists of mucous membrane lined tube airways goes from the trachea to the alveoli

Alveolar ducts branch off the respiratory bronchioles, then come the alveolar sacs which contain alveoli, and lastly alveoli conduct gas exchange and are surrounded by capillary networks

separated by the mediastinum, and are surrounded by the thoracic cage and the diaphragm

large blood vessels enter each lung on the surface

Soft spongy organs of the respiratory system

Right lung is larger than the left one

Right lung has 3 lobes (superior, middle, and inferior)

Left lung has 2 lobes (superior and inferior)

Respiratory Capacities (combinations of respiratory volumes)

There are 4 distinct respiratory volumes

Tidal Volume - volume of air that enters or leaves the lungs during one cycle (around 500mL)

Inspiratory Reserve Volume - volume of air that can be inhaled in addition to the tidal volume ( about 3,000 mL)

Expiratory reserve volume - the max volume of air that can be exhaled beyond just the tidal volume which is around 1200 mL

Residual Volume - volume of air left in the lungs after a max expiration (about 1200 mL) and this cannot be measured with a spirometer

Functional Residual Capacity - volume of air that remains in lungs after a expiration ERV + RV = ~ 2300 mL

Vital Capacity - the max amount of air that can be exhaled after a max inhale TV + IRV = ~ 4600 mL

Inspiratory capacity - volume of air inhaled after a normal expiration IRV + TV = ~ 3500 mL

Total Lung Capacity - total volume of air the lungs can hold, VC + RV = ~ 5800 mL this number can vary depending on body size and age

Internal respiration occurs when the gasses are exchanged inside of the body

External respiration occurs in the lungs when oxygen goes into our blood and CO2 diffuses into the alveolar air

Inspiration

Expiration

External Intercostals contract to move ribs and sternum up and outwards

these muscle contractions result in pressure change in lungs -2 mm below the atmospheric pressure, this causes the air from the outside to rush in

Diaphragm contracts and moves downward which enlarges the thoracic cavity

Has tubes that warm, filter, and moisturize incoming air, the air then gets transported to gas exchange areas to exchange o2 for co2

It also removes particles from the incoming air, provides our vocal sounds, regulates our blood pH, and helps with our sense of smell

Get oxygen from the atmosphere and remove carbon dioxide from the body's cells

Tuberculosis - a contagious bacterial/viral infection of the lungs, can be treated by antibiotics, surgery, or meds, but some variants cannot be treated

Pneumonia - bacterial/viral infection of the lungs this can be treated by meds, antibiotics, or oxygen therapy

Chronic obstructive pulmonary disorder (COPD) - can be caused by smoking, air pollution, or age and can be treated thru medication oxygen therapy or lung transplant

Lung Cancer - is uncontrolled cell growth or tumors in the lungs this can be caused by smoking, genes, or air pollution, and this can be treated by chemo, radiation, or surgical removal

air moves from higher pressure to lower pressure areas so when the pressure in the lungs drops the air from the outside rushes into the lungs atmospheric pressure = 760 mm Hg

During inhalation the alveolar pressure is -1 that of the atmospheric pressure which causes the air to enter the lungs

During exhalation the alveolar pressure is +1 that of the atmospheric pressure which forces the air out of the lungs and back into the atmosphere