What is the major function of the respiratory system?
Supply oxygen for aerobic repiration and remove and dispose of carbon dioxide
What are the 5 phases of the res. system?
- Pulmonary Ventilation
- External respiration
- Transport of respiraotry gases
- Internal respiration
What is pulomnary ventilation?
Breathing, passively, the movement of air in and out of the lungs
What is external respiration?
Gas exchange between the blood and air filled chambers of the lungs
WHat is transport of repiratory gases?
Movement of gases within the body, accomplished using the cardiovascular system
What is internal respiration
Exchange of gases btwn blood and tissues
What comprises the conduction zone of the respiratory system?
- Cleanses, humidies, and warms incoming air
What does the respiratory zone comprise of
- Alveolar ducts
- Alveolar sacs
- Microscopic Structures
Describe the conduction zone
Rigid conduits for transport of air to resp. passages
Describe the respiratory zone
Site of gas exhange
What are the physical barriers in the nose?
- Vibrissae-nose hairs
- Olfactory mucosa-receptos for smell
- Repsiratory mucosa-made of pseudostratidfied columnar epithelia, glblet cells, serous cells:lysozyme and defensins
What are vibrissae?Function?
- Nose hairs
- Filter course particles from entering the respiratory pathway
What is the respiratory mucosa made of? (cells)
Pseudostratified columnar epithelia
Within the repsiraotry mucosa, what cells are present? Thier use?
- Goblet cells: mucous cells
- Serous cells: Enzymes
- Lysozyme: Antibacterial enzyme
- Defensins: Antibiotics that aid in bacterial defense
Once past the epiglottis, you reach the ____
voice box, larynx
In humans, sound is produced by the opening and closing of the ____, with post-laryngeal filtering for specificity
Loudness depends on the force of the ___ air, increasing vibration within the vocal folds
Glottis wide = ____ tones (frequency, in Hertz (Hz)
Glottis thin = ___ tones (Hz)
Describe the trachea
Long, flexible tube that directs air to the bronchi
As air enters the respiratory zone, changes in cartilage structure are . . .
From rings o plates, to none being replaced by elastic fibers (found throughout the respiratroy tree)
As air enters the resp. zone, the epithelium changes . . .
From ciliated pseudostratified, to columnar, to cuboidal, to squamous in the ducts and sacs
As air enters the resp. zone, the amount of smooth muscle increases . . .
Allowing constriction of the passageways
What allows for the recoil passively in breathing?
Simple squamous epithemium(Type __) with a fused basal lamina form the ____.
Type __ cells in respiratory membrane secrete ______ for blood pressure regulation.
- Angiotensin converting enzyme
Cuboidal(Type__) cells secrete _____.
______ allow air pressure throughout the lung to be equalized if alveolar ducts collapse by disease or damage
______ destroy microorganisms and pathogens
Alveolar macrophages (dust cells)
Lungs occupy the entire thoracic cavity except the _____ (surrounding the heart)
P^alv is the pressure in the alveoli, rising and falling with the phases of breathing, but ______ to external P^atm
Pressure in the______also fluctuates, but remains about 4mHg below Patm
pleural cavity (P^ip)
Keeps Lungs from ___.
Neg. P^ip established on 2 forces.
Elasticity of chest wall pulls the thorax_____, enlarging the lungs
Lungs pulled from the thorax by ____.
____changes lead to pressure changes, which lead to the flow of gases to equilibrate pressures
Pulmonary Ventilation. Define.
Volume-Pressure-Flow of gas
What law define the relationship between pressure and volume?
Drag is calculated as . . .
Gas flow inversely related to _____
Large changes in flow can occur with ___ changes in pressure
Gas flow stops at terminal bronchioles, and ____takes over in driving molecule movement
Highest resistance at _____.
_____ of smooth muscle changes resistance
Water (polar molecule) has a ___ surface tension
Lining has _____: detergent-like complex of proteins and lipids produced by type II cells
Molecules more attracted to one another at surfaces than to other types (liquid versus gas) creating ____ in alveolar surface
What interferes with the cohesiveness of water molecules, allowing expansion?
No _____? Lungs unable to inflate!!
Lung compliance is diminished by
Fibrosis, blockage of passages, low surfactant, decreased thoracic expansion, etc.
Lungs distensible: the amount of stretching termed _____.
CL = VL/(P^alv – P^ip)
___volume (TV): Air in and out normally (500 ml)
____ volume : air forced beyond tidal volume (2100-3200 ml)
____ volume : air forced out of lungs (1200 ml)
____ volume: air left in lungs, preventing collapse
____ capacity (IC): amount that can be inspired after tidal expiration (sum of tidal and inspiratory reserve volumes)
____ capacity: amount of air left in the lungs after tidal expiration (combined inspiratory and expiratory volumes)
____ capacity: The total amount of exchangeable air (~4800 ml)
____capacity: The sum of all capacities (~6000 ml)
Dalton’s law of partial pressures
The total pressure exerted by a mixture is the ___ of the pressures exerted independently by each gas in the mixture
Each gasses pressure, or ____, is directly proportional to it’s percentage in the mixture
In a mixture of gas, each gas will dissolve in the ____ in proportion to its partial pressure
The more there is, the greater and faster it will dissolve
According to Dalton’s Law
_____ moves out of the blood into the alveoli
____ moves out of the alveoli into the blood
____ moves out of the blood into the alveoli
- Carbon Dioxide
External respiration. Define
O2 and CO2 within the lungs gas exchange
same gases move in the opposite direction by the same mechanism (diffusion!)
Factors influencing movement of respiratory gases
Partial pressure and gas solubility
Functional aspects, like matching alveolar ventilation with pulmonary blood perfusion
Structural characteristics of the membrane (i.e. thickness)
Note that it takes only about ____ seconds
for the blood to get oxygenated.
Thus, blood can flow ___ as fast as normal and still get oxygenated.
Fully or partially saturated ___ groups
The off-loading of oxygen is not linear, instead being an ____ (the oxygen-hemoglobin disassociation curve)
Causes full saturation at 70 mmHg, and easily offloads oxygen with small pressure changes
Several factors influence the offloading of oxygen:
- H+ concentration (pH)
- BGP (2,3-biphosphoglycerate, which binds reversibly to hemoglobin, produced during anaerobic respiration)
Increasing these factors decreases Hb’s affinity for oxygen
Decreasing these factors increases Hb’s affinity for oxygen
The Bohr effect
Increased activity raises the ____ of an area, which shifts offloading of oxygen to these tissues
Also under hormonal control (endocrine system), such as thyroxine, epinephrine, growth hormones, and catchecholamines
The Bohr effect
In capillaries, ___and ___ being used creating carbon dioxide (increasing H+ (decrease pH), PCO2)
____ (decreased pH) weakens hemogloboin-oxygen bond, accelerating oxygen offloading (shifts the curve to the right), a phenomenon termed the Bohr effect
Hemoglobin (Hb) and Nitric Oxide (NO)
NO a ____
Hb a ____
Local vessels dilate where gases are unloaded. WHY?!?
NO(nitric oxide) attached to a cystene group and protected from degradation by the iron group in Hb. Oxyhemoglobin unloads oxygen and NO, aiding in oxygen delivery. Deoxyhemoglobin then scavenges NO and CO2, and unloads in lungs
CO2 transported 3 ways.
Dissolved in plasma (7-10% as CO2)
Chemically bound to Hb (~20% as carbaminohemoglobin)
As Bicarbonate ion in plasma (~70% converted to HCO3-)
CO2 + H2O H2CO3 H+ + HCO3-
CO2 produced in cells (~200ml/min), _____ as released by the lungs
What is Carbonic Anhydrase?
Enzyme that catalyzes the conversion to carbonic acid (in RBC’s)
____ ions diffuse from RBC’s to plasma after carbonic anhydrase
After carbonic anhydrase, Chloride ions move from the plasma to RBC’s to counterbalance: ionic exchange is termed the _____
What is described as :
The less oxygen in the blood, the more the blood can carry carbon dioxide
If there is an increase in O2 there is less CO2 because deoxyhemoglobin forms _____ and buffers H+ by combining with it.
Thus, the haldane effects allows for the formation of more bicarboinate ions
Influence of CO2 on blood pH
Most important function is that it acts as a ______
The ______ system resists shifts in pH by counterbalancing H+ levels
- bicarbonate reserve
- carbinic acid-bicarbinate buffer
Neural control of breathing
Control from the reticular formations of the _____
Medulla forms the ____
Pons controls regulates the rhythm and _____ of inspiration and expiration
- medulla and pons
- smooths the transitions
High CO2 stimulates breathing (and vice verse)
Changes in ____ indirectly affects peripheral chemoreceptors, changing the rate of breathing (thus, PO2, PCO2 , and pH)
PO2 influences chemoreceptors; high levels diminish CO2 stimulation
Squamous cell carcinoma, where?
Small cell carcinoma, where?
- bronchi epithelia
- peripheral lung areas
- primary bronchi
What is emphysema?
Destruction of avelor walls.