Respiratory System By Abigail Camba Paulin Slear Sokmany Soeum

Functions  Movement of air into & out of the lungs  Gas exchange between the blood & the air in the lungs  Gas transport in blood between the lungs & the body cells  Gas exchange between the blood & the cells

 Part of the face centered about the mouth, in and below space between eyes  Has two nostrils that are openings where air can enter and leave the nasal cavity  Has many internal hairs for protection (filtration of incoming hair) Structures of the System Nose

Nasal Cavity  Hollow space between behind the nose  The nasal septum divides the nasal cavity to a left and right portion  Nasal conchae are bones that create walls, making the cavities into passageways

Paranasal Sinuses  Air filled spaces located within the maxillary, frontal, ethmoid, and sphenoid bones of the skull  Reduces weight of skull  Resonant chambers that effect quality of voice

Pharynx (aka Throat)  Located behind the oral cavity, the nasal cavity and the larynx  Passageway for food and air passing  Produce sounds of speech

Nasopharynx  Passageway for air  Auditory tubes

Oropharynx  Passageway for food  Posterior to soft palate  Inferior to nasopharynx

Larypharynx  Passage to esophagus  Inferior to oropharynx

Larynx  Located at the top of the trachea & below the pharynx  Contains air in & out of the trachea  Prevents foreign objects from entering  Houses vocal cords

Trachea (aka windpipe)  Extends downward anterior to the esophagus and into the thoracic cavity  Flexible tube that connects larynx with bronchial tree  Passageway for air as well as filters it  Contains 20 C-shaped pieces of hyaline cartilage

Bronchial Tree Bronchial tree left/right primary bronchi secondary bronchi tertiary bronchi bronchioles alveolar ducts alveolar sacs alveoli  Branched tubes that lead from the trachea to alveoli  Alveoli are large surface areas where gas can be exchanged  Structure is similar to the trachea

Lungs  Soft, cone-shaped organs that occupy a large portion of the thoracic cavity  Right lung is larger than the left  Contains air passageways, alveoli, blood vessels, connective tissues, lymphatic vessels and nerves of the lower respiratory system

Pleural wall

Breathing Mechanism (aka ventilation) Movement of air from outside of the body into and out of the bronchial tree and alveoli InspirationExpiration

Inspiration  Atmospheric pressure is the force that moves air into lungs  Occurs when pressure inside alveoli decreases  Diaphragm contracts and rises as air comes into lungs  Pleural membranes play a role in expansion of lungs

Expiration  Force comes from elastic recoil of tissues and surface tension  Abdominal organs return to original shape  Decreases diameters of alveolar

Respiratory Air Volumes and Capacities  Respiratory cycle = 1 inspiration + 1 expiration  4 distinct respiratory volumes : - Tidal/ Resting tidal volume -Inspiratory reserve volume -Expiratory reserve volume -Residual volume Spirometry measures air volumes of different intensities in breathing

Tidal Volume/Resting  Enters/leaves 1 respiratory cycle  500ml of air (normal) Residual Volume  Air in lungs after exhales the tidal volume  Prevents fluctuation  1,200ml of air Inspiratory/ expiratory Volume  Volume of air inhaled/exhaled in addition to tidal/resting  3,000ml of air (I)  1,100ml of air (E) Volumes

Capacities Vital capacity  Combination of inspiratory reserve volume, tidal volume and expiration volume  Maximum amount of breathe exhaled  4,600ml of air Inspiratory capacity  Tidal volume plus inspiratory reserve volume  Maximum amount of air inhaled

Capacities (continued) Functional residual capacity  Expiratory reserve volume and residual volume  Amount of air remaining in lungs  2,300ml of air Total Lung Capacity  Vital capacity and the residual volume together  (about 5,800ml)  Varies in age, sex, and body size

Respiratory Center  Controls breathing depth and rate  Group of neurons scattered in pons and medulla  Pons: pneunmotaxic area  Medulla: rhythmicity area

Pons  Pneumotaxic area  Control breathing rate  Strong = bursts short, breathing increase  Weak= long bursts, breathing rate decrease

Medulla  Dorsal respiration group: control rhythm  Signal diaphragm and other muscles  Increase volume of air entering  Ventral respiratory group: increase inspiratory movement

Alveolar Gas Exchanges  Microscopic air sacs clustered at the distal ends of alveolar ducts  Respiratory membrane consists of alveolar and capillary walls  Blood and alveolar air exchange gases across membrane

Diffusion across membrane  Diffuses from regions of higher blood pressure  21% Oxygen, 78% Nitrogen,0.04% Carbon Dioxide, 0.996% other  Oxygen diffuses from alveolar air into blood  Carbon dioxide diffuses from blood into alveolar air Partial pressure of a gas is proportional to the concentration of gas in a mixture or the concentration dissolved in a liquid

Oxygen transport  Gas enters as a liquid  Blood transports O2 and CO2 between the lungs and cells  Gases enter in blood (98% hemoglobin, 2% plasma)  Oxyhemoglobin is form when blood and iron atoms combine

Carbon dioxide transport  CO2 transport to lungs in 3 ways: dissolved in plasma (7%), dissolved in plasma (7%), compound with hemoglobin (23%) compound with hemoglobin (23%) and a bicarbonate ion (70%) and a bicarbonate ion (70%)

Plasma  Determined by partial pressure  Amount of Pco2 in the tissues = more Co2

Hemoglobin  CO2 combines with amino group (-NH2) for protein  CO2 loosely bonds with carbaminohemoglobin but forms slowly (most effective)

Biocarbonate ions  CO2 reacts with H2O  Has carbonic anhydrase that speeds up the process  Creates carbonic acid

Factors Affecting Breathing  Chemicals  Stretching of lung tissues  Emotional states

Chemosensitive areas  Sense changes in the cerebrospinal fluid (CSF) concentrations of CO2 and hydrogen ions  Stimulation of these receptors increases breathing rate

Peripheral chemoreceptors  Sense change in low blood concentrations  Located in walls of arteries in the neck and thorax  Oxygen plays small role

Inflation reflex  Occurs when lung tissue stretches  Shortens duration of inspiration breathing  Prevents overinflation of lungs when forceful breathing

Emotional factors  Increase breathing rate  Voluntarily stop breathing  Hyperventilation, resulting in fainting

Diseases in the Respiratory System Asthma Asthma  Lung disease that inflames and narrows the airways  Over 25mil people have it in the U.S., 7mil are children  No cure, but treatments are available (such as inhaler) Bronchitis  Inflammation of bronchial tubes  Usually caused to sickness (viruses) or smoking  Take medications: antibiotics, cough or medicine

Works cited conditions/bronchitis/basics/definition/con conditions/bronchitis/basics/definition/con &doctype=1 87&doctype=1 the-innate-immune-system/ the-innate-immune-system/