Respiratory+System

=__THE RESPIRATORY / BREATHING SYSTEM__ =

__Functions of the system__:
Provide a source of oxygen and remove carbon dioxide from the body.

Plays a role in maintaining blood pH

__ANATOMY OF THE SYSTEM__
System of Airways/Breathing passages Anatomically Functionally

Upper Airways / Upper Respiratory Tract Conducting Zone Nose and Pharynx All passages up to bronchioli Lower Respiratory Tract Respiratory Zone Larynx Trachea — alveoli Smaller bronchioli --, alveoli

NB For other diagrams please refer to the text book
__**the NOSE**__ Know diagram of structure External and internal structure Bones: Frontal bone with sinus

Ethmoid bone with sinuses, conchae etc.

Sphenoid bone with sinus

Maxillae with sinuses

Palatine bones

Vomer Cavities: External nares, nasal cavity, internal nares

inferior -, middle and superior meatuses, nasopharynx Adaptations: mucous glands, hairs, cilia, richly vascularised epithelium.

Functions of nose: Perfect air conditioner
__**the PHARYNX**__ All divisions and structures in pharynx and their functions.

pharyngeal tonsils (adenoids), palatine and lingual tonsils.

__**the LARYNX**__

All divisions and structures in larynx and their functions.

Functions of the epiglottis

Vocal cords (true and false)

Diagrams to be well memorized

__**the TRACHEA**__

Detailed structure

Tissue types and shapes

Point of bifurcation, carina
 * __BRONCHI__**

Relative sizes and positions of the primary bronchi

Progression into bronchioles –>> terminal bronchioles

Changing of mucous membrane from pseudostratified ciliated columnar epithelium to

simple cuboidal epithelium in terminal bronchioles

Changing of shape of cartilagenous rings.

Changing of the layering of smooth muscle in the airways.


 * NOTE THE DIFFERENCE IN BRONCHIAL TREES OF THE LEFT AND RIGHT LUNG**


 * 1. Positions of primary bronchi**
 * 2. Number and names of secondary bronchi**


 * __the LUNGS[[image:lungsribs.jpg width="348" height="322" align="right"]]__**

Position, shape and comparative sizes; lobes, fissures and lobules
 * Know diagrams very wel**l

Cavities, membranes and fluids

Alveolar duct with alveolar sacs - cell types, role of surfactant

GE surface: 4 layers



__**BLOOD SUPPLY TO THE LUNGS**__ Supply: Pulmonary arteries, Bronchial arteries

Drainage: Mostly Pulmonary veins; little via Bronchial veins –>> SVC

ventilation perfusion coupling

__PHYSIOLOGY OF THE SYSTEM__
We inhale air with whatever is in the air Composition of air:.............

__**PULMONARY VENTILATION**__ Phases /components of the process

Inhalation and Exhalation in detail:

Muscles and other structures involved - effects on partial pressures



Boyle’s Law ; Hering-Breuer reflex Factors affecting Pulmonary ventilation: Surface tension of alveolar fluid ; Lung Compliance ;

Airway resistance

Reflect of process of diffusion
 * __[[image:HaldanEffect.jpg width="442" height="260" align="right"]]GASEOUS EXCHANGE__**

External respiration ( G E in lungs)

Internal respiration (GE at cell surfaces)

Factors affecting rate of Exchange: PP’s - Dalton’s Law, Henry’s Law ;

Surface area ; Diffusion distance;

MM and solubility of gases

Dead space: anatomic & physiologic

Graph of relative average volumes
 * __LUNG VOLUMES AND CAPACITIES__**

Definitions and significance of each of the volumes & capacities

Relationship between Hb and OxygenPP
 * __OXYGEN TRANSPORT__**

Other factors affecting the affinity of Hb for oxygen : pH, PpCO2 , O2-Hb dissociation curve.... **the role of the NOSE in heating inhaled air** temp.,

Hb-F vs Hb-M



BPG (DPG)

3 ways in which CO2 is transported
 * __CARBON DIOXIDE TRANSPORT__**

Chloride shift

Haldane effect, role of carbonic anhydrase

__CONTROL OF BREATHING/RESPIRATION__
Feedback mechanisms in play Respiratory Centre: Medullary Rhythmicity area in Medulla Oblongata

Pneumotaxic and Apneustic areas in Pons Regulation of Respiratory Centre:

Cerebral Cortex - voluntary intervention mechanism for protection

Chemoreceptors: Central in MO

Peripheral in aortic bodies and carotid bodies Hypercarbia/hypercapnia - hyperventilation Hypocarbia/hypocapnia - hypoventilation

Proprioceptor stimulation - positions and tensions in muscles

Inflation reflex - baroreceptors (Hering-Breuer reflex)

Limbic system - basic instincts - emotionally driven

Temp, Pain, Anal distension, Irritation of airways, Blood pressure

__DISORDERS AND HOMEOSTATIC IMBALANCES OF THE BREATHING SYSTEM__
Hypoxia : Hypoxic, anemic, ischemic, histotoxic Carbon monoxide poisoning Asthma COPD Chronic Obstructive Pulmonary Disease (COLD/CORD) Emphysema Chronic Bronchitis Lung Cancer Particular attention to SMOKING Pneumonia Coryza & Influenza Pulmonary Edema Cystic Fibrosis SIDS SARS Asbestos-related diseases

__**OTHER TERMINOLOGIES TO KNOW**__

Haemothorax, pneumothorax, atelectasis

Abdominal Thrust maneuver (Heimlich maneuver) Asphyxia, Aspiration, bronchiecstasis, Cheyne-Stokes respiration Dyspnea, apnea, sleepapnea, Hypoventilation, Hyperventilation/Tachypnea, mechanical ventilation, Rales, Respiratory failure, wheezing Hyperbaric oxygenation

__**INNATE CAPACITY OF LUNGS TO FIGHT DISEASES**__



Removal of chemical like neurotransmitters and paracrine agents
 * __NON-RESPIRATORY FUNCTIONS OF THE LUNGS__**

Angiotensin II

Removal of small blood clots

__EXAMPLE OF A GLOSSARY__

 * alveolar duct** - The terminal branch(es) of each respiratory bronchiole in the lungs, lined by a simple squamous epithelium, which deliver inspired air to the alveolar sacs.


 * alveolar sac** - A cluster of alveoli located at the end of each alveolar duct in the lungs; each of the alveoli is a tiny, thin-walled, capillary-rich sac, lined by a simple squamous epithelium, where the exchange (diffusion) of oxygen and carbon dioxide (and other less important gases) takes place.


 * alveolus** - (1) A tiny, thin-walled, capillary-rich sac in the lungs, lined by a simple squamous epithelium, where the exchange of oxygen and carbon dioxide (and other less important gases) takes place; the approximately 300 million alveoli have a total cross-sectional area of 50- 70 m2, which equals ~40 times the surface area of the skin. aka - air sac (2) A tooth socket in the jawbone.


 * type I alveolar cell** - The squamous epithelial cell forming the alveolar wall and through whose cell membranes and cytoplasm the exchange of oxygen and carbon dioxide (and other less important gases) takes place; collectively they cover 95% of the alveolar surface area.


 * type II alveolar cell** - The cuboidal cell found as a minor component of the alveolar wall, they are scattered among the type I cells and account for only 5% of the alveolar surface; they have three main functions: (1) secretion of surfactant, (2) control of alveolar fluid levels by water recapture using active sodium transport to return excess alveolar surface water to the interstitial fluid, and (3) the stem or progenitor cell which can proliferate to replace both type I and type II cells after injury.


 * alveolar macrophage** = dust cell - The large mobile cell, derived from the monocyte, occurring in low numbers within the connective tissue of the alveolar walls and, more commonly, patrolling on the walls of the alveoli, which ingests by phagocytosis any foreign particles and infectious microorganisms which reach the alveoli; they may also transport indigestable materials such as soot or silica dust to the lymph nodes of the lungs for storage.


 * FUNCTIONS NEED NOT BE INCLUDED IN THE GLOSSARY. Alternately you could construct a table with "word, location and function" columns.**