RESPIRATORY SYSTEM

PRIMARY FUNCTIONS Exchange gases (oxygen and CO2) Produce vocal sounds Sense of smell Regulate blood pH

LUNG CAKE

Respiration - process of gas exchange 1.  Movement of air into lungs 2.  External respiration - between blood and air 3.  Gas transport in blood 4.  Internal respiration - between blood and body cells

Why do we need oxygen? MITOCHONDRION Cellular respiration = cells use oxygen and sugars to create energy in the form of ATP *ATP is then used to power cellular processes MITOCHONDRION

Overview of the Respiratory System Upper Respiratory Tract – nose, nasal cavity, sinuses, pharynx Lower Respiratory Tract – larynx, trachea, bronchial tubes, lungs

The NOSE bones and cartilage support nose, two openings (nostrils) hair filters large particles Nasal Cavity – hollow space behind the nose  Nasal septum – divides the nose (bone)

* deviated septum – when the septum bends to one side, results in the nose being crooked. Plastic surgeons repair this by breaking and re-setting the bone.

Nasal concha – bones that divide the nasal cavity, support the mucus membrane and increase surface area (superior, middle, inferior)       Mucus Membrane - warms and moistens air, also traps particles (dust)     *particles go to          stomach

maxillary frontal ethmoid sphenoid Paranasal Sinuses - spaces within the  bones They are named after the bones: maxillary frontal ethmoid sphenoid    reduce the weight of skull and are resonant chambers for voice.

nasopharynx oropharynx laryngopharynx Pharynx – behind the oral cavity, between the nasal cavity and larynx (space, not a structure)   nasopharynx oropharynx laryngopharynx

Larynx – enlargement at the top of the trachea, houses vocal cords              composed of muscles and cartilages -thyroid (Adam’s apple), -cricoids, -epiglottic cartilage

GLOTTIS: the part of the larynx consisting of the vocal cords and the opening between them. It affects voice modulation through expansion or contraction. - false vocal folds  – help close airway during swallowing (do not produce sound)             - true vocal folds - produce sound             - contracting and relaxing muscles changes pitch (increased tension = higher pitch)

Glottis – triangular slit that opens during breathing/talking, and closes during swallowing Epiglottis – flaplike structure that stands upright, allows air to enter larynx, it closes during swallowing to prevent food from entering the airway

LARYNGITIS Laryngoscope Inflammation of the larynx that makes the voice hoarse, or the person loses their ability to speak. Caused by illness, allergies, smoking, some medications. If you have chronic laryngitis, you might want to see an OTOLARYNGOLOGIST Laryngoscope

Trachea (windpipe) flexible cylinder with cartilage to give it stiffness and keep it from collapsing Trachea leads to the BRONCHIAL TREE

Trachea → Primary Bronchi → Secondary Bronchi → Tertiary Bronchi → Bronchioles

Bronchioles have air sacs called alveoli which are connected to the circulatory system via capillaries

LUNGS - spongy tissue that sit within the pleural cavity

Right Lung          = 3 lobes Left Lung           = 2 lobes Cardiac notch - space for heart Serous fluid lubricates lungs during breathing

Quick Quiz 1.  What do you call the bones found within the nasal cavity? 2.  What specific bone divides the nasal cavity into two sides? 3.   The space at the back of the mouth is the________. 4.  The spaces within the bones of the skull are called the ______________________ 5. What structure is known as the windpipe? ______ 6.  What is the triangular slit that opens during breathing and talking? 7. In what structures does gas exchange occur? 8. During swallowing, this flap closes to prevent food from entering the airway: ______________________

BREATHING MECHANISM

1.  Diaphragm moves down, forcing air into airways 2.  Intercostals contract, enlarging cavity even more 3.  Surface tension in alveoli and surfactant keep them from collapsing 4.  Other muscles can force a deeper breath 5. Relaxing the diaphragm causes elastic recoil(exhalation)   *The first breath in newborns is the hardest due to lack of surfactant

As the diaphragm and other muscles relax, ELASTIC RECOIL from surface tension forces air out.   Muscles can force extra air out or in EXHALATION

Image adapted from http://www.arthursclipart.org/