FUNCTIONS OF RESPIRATORY SYSTEM
- gas exchange (CO2, O2)
- sound production
STRUCTURES OF THE RESPIRATORY SYSTEM
- external nose
- nasal cavity
- pharynx (throat)
- larynx (voice box)
- trachea (windpipe)
- bronchi (branches of the trachea)
- moisten & warm incoming air
- nares, pharynx, sinuses, larynx
- The pharynx is a five-inch long tube that starts near our nose and ends at our windpipe. The pharynx is generally considered a part of the throat.
FUNCTIONS OF THE PHARYNX
- not an organ, a location
- receives air from the nasal cavity & receives air, food, & drink from the oral cavity
FLOW OF AIR THROUGH THE PHARYNX
- the upper part of the pharynx, connecting with the nasal cavity above the soft palate.
- the part of the pharynx that lies between the soft palate and the hyoid bone.
- the lower part of the pharynx, extending from the upper tip of the epiglottis to the larynx and esophagus
- voice box
- maintains open passageway for air movement
- passageway for air between the pharynx & trachea
- prevents swallowed materials rom entering resp tract
- epiglottis: closes as you swallow
- incomplete rings of cartilage hold it in place connected to one another by muscles & ligaments
- consists of dense regular connective tissue & smooth muscle
- 15-20 c-shaped pieces of hyaline cartilage reinforce it
- pseudo-stratified columnar epithelium
- allows air to flow into the lungs
STRUCTURE OF THE BRONCHIAL TREE
- the trachea and all other respiratory passages in the lungs
- primary bronchi>secondary bronchi>tertiary bronchi>bronchioles
- airway in the resp. tract that conducts air into the lungs
- branch from primary bronchi delivers oxygen to the three lobes of the right lung and two lobes of the left long
- where air moves
- starts at the nose ends at the terminal bronchiole. (pharynx, larynx, trachea, bronchi)
- Respiratory bronchioles and down (alveolar ducts and alveoli)
- where gas exchange happens
- super thin bags where we perform most gas exchange
- surrounded by capillaries
- simple squamous epi.
- connect bronchioles to alv. sacs
ALVEOLAR CAPILLARY BEDS
When we breathe, air enters our lungs and fills tiny air sacs called alveoli. Each air sac is surrounded by an extensive capillary bed, which is a network of tiny, thin blood vessels. In order for us to bring in oxygen and release carbon dioxide, the alveoli and capillaries must be properly aligned.
- Type I: just makes up the wall of the alveolus
- Type II: reduces surface tension. keeps alveolus open
- no surfactant=lung collapses
- lining of the walls of the thoracic cavity (visceral and parietal layers)
- thin fluid-filled space that lies between the pleura membranes
- cavity in the vertebrate body enclosed by the ribs between the diaphragm and neck containing the lungs and heart
LOBES OF THE LUNG
- Right: three lobes. superior, middle and inferior. two fissures, one oblique and one horizontal
- left: two lobes. superior & inferior. one oblique fissure
- air in pleural space
- partial or complete lung collapse
- describes the relation of presure of gas and volume
- how we control ventilation. ^ pressure, v volume.
DALTON'S LAW OF PARTIAL PRESSURES
- in a mixture of gases, each gas exerts a pressure equal to its amount
at a given temperature, amount of a gas in a solution is directly proportional to partial pressure of the gas.
- "that diffusion thing, works into and out of a liquid too"
2 TYPES OF GAS EXCHANGE
- Pulmonary Gas Exchange
- Systemic Gas Exchange
PULMONARY GAS EXCHANGE
- Blood is sent to the lungs to gain O2
- Blood is sent from R. Ventricle to the lungs to dump CO2
- The pressure of O2 from the alveoli is higher than the pressure in the pulmonary capillaries. O2 moves into pulm. Caps.
- Reverse for CO2. The pressure is higher in the pulm caps than the alveoli so CO2 moves out.
SYSTEMIC GAS EXCHANGE
- Blood is pumped via aorta to the rest of the body to dump/deliver O2 and pick up CO2 made by tissue and brought back to heart
- Pressure of O2 is higher in blood than the tissues, O2 moves out to the tissues.
- Pressure of CO2 is higher in the tissues, CO2 moves out into the blood.
RESPIRATORY STRUCTURES & BRAINSTEM
- pontine respiratory group (pons) >Medullary resp center
- Phrenic nerve: diaphgram (inspiration)
- Intercostal nerves
- Internal intercostal nevers: expiration
- External intercostal nerves: inspiration
MAJOR REGULATORY MECHANISMS OF VENTILATION
- Slows down ventilation: speech, emotions, stretch receptors in lungs
- Increases ventilation: action potentials, speech, medullary chemoreceptors, carotid and aortic body receptors
- proprioceptors in muscles and joints, and receptors for touch, temp. and pain
- hemoglobin changes shape when carrying CO2 or O2, displacing the other
- the exchange of HCO3- and Chloride
- Hb's oxygen binding affinity is inversely related both to acidity and to the concentration of CO2
- measure of the lung's ability to stretch and expand
ROLE OF DIAPHRAGM
- Contracts: moves lower and chest cavity enlarges. (increase in volume, decrease in pressure in lungs)
- Relaxes: moves back up (decrease in volume, increase in pressure)
- normal volume of air inspired and expired with each breath
INSPIRATORY RESERVE VOLUME
- amount of air that can be inspired forcefully after a normal inspiration
EXPIRATORY RESERVE VOLUME
- amount of air that can be forcefully expired after a normal expiration
- volume of air still remaining in the respiratory passages and lungs after the most forceful expiration
- tidal volume plus inspiratory reserve volume
- amount of air a person can inspire maximally after a normal expiration
FUNCTIONAL RESIDUAL CAPACITY
- expiratory reserve volume plus the residual volume
- amount of air remaining in the lungs at the end of a normal expiration
- maximum volume of air a person can expel from the respiratory tract after a maximum inspiration
TOTAL LUNG CAPACITY
- sum of inspiratory and expiratory reserve volumes plus the tidal volume and the residual volume
FORCED EXPIRATORY VITAL CAPACITY
- simple and clinically important pulmonary test
- inspire maximally, exhales maximally.
act of cutting into the trachea
inflammation of the pleura
Tuberculosis (TB) is a disease caused by bacteria called Mycobacterium tuberculosis. The bacteria usually attack the lungs, but they can also damage other parts of the body. TB spreads through the air when a person with TB of the lungs or throat coughs, sneezes, or talks.
ANTHRACOSIS (BLACK LUNG)
black discoloration of bronchi from carbon pigment that typically causes deformation and obstruction, may be asymptomatic or cause respiratory symptoms (such as cough and labored breathing), and is often associated with the inhalation of coal dust and wood smoke
Chronic obstructive pulmonary disease (COPD) is a lung disease characterized by chronic obstruction of lung airflow that interferes with normal breathing and is not fully reversible. The more familiar terms 'chronic bronchitis' and 'emphysema' are no longer used, but are now included within the COPD diagnosis.
a condition in which the air sacs of the lungs are damaged and enlarged, causing breathlessness."smoking can lead to serious lung diseases such as emphysema"
- a hereditary disorder affecting the exocrine glands. It causes the production of abnormally thick mucus, leading to the blockage of the pancreatic ducts, intestines, and bronchi and often resulting in respiratory infection.
also called the flu, is a common but sometimes serious viral infection of your lungs and airways. It can cause congestion, fever, body aches, and other symptoms
- breathing at an abnormally slow rate, resulting in an increased amount of carbon dioxide in the blood.
a condition in which you start to breathe very fast
the uncontrolled growth of abnormal cells in one or both lungs. These abnormal cells do not carry out the functions of normal lung cells and do not develop into healthy lung tissue.
LIST THE WAYS THAT BLOOD GASES ARE TRANSPORTED IN THE HUMAN BODY
- A small amount of O 2(1.5 percent) is carried in the plasma as a dissolved gas.
- Most oxygen (98.5 percent) carried in the blood is bound to the protein hemoglobin in red blood cells. A fully saturated oxyhemoglobin (HbO 2) has four O 2 molecules attached. Without oxygen, the molecule is referred to as deoxyhemoglobin (Hb).
MEDULLARY RESPIRATORY CENTER
Sets the basic rhythm of breathing
VENTRAL RESPIRATORY GROUP
- active during both inspiration & respiration
- primarily stimulate the external intercostal, internal intercostal, & abdominal muscles
- Pre-botzinger complex: is believed to establish the basic rhythm of respiration
DORSAL RESPIRATORY GROUP
primarily responsible for stimulations contraction of the diaphragm
PONTINE RESPIRATORY GROUP
connection with the medullary respiratory center & appears to play a role in switching between inspiration & expiration, thus fine-tuning the breathing pattern