EXAM 3: SEC2/Breathing Flashcards
1
Q
Resp system functions
A
- bring atmospheric air into body and provide opportunity for diffusion of O2 and CO2 across resp. membrane
- blood carries O2 to tissues and CO2 away from
2
Q
Specialized Functions of Resp
A
- controlled ventilatory movements with fine control of oval muscles allow for taling
- mucociliary lining of conduction system helps prevent harmful matter into body and infectious organism
- endothelial lining activates/deactivates certain chemical messengers
- pulmonary capillary bed traps emboli from legs or other regions may prevent clots from reaching brain and heart
- diaphragm is primary muscle for quiet breathing
3
Q
Airway in order
A
- trachea
- bronchi
- bronchioles
- terminal bronchiolea
- resp bronchioles
- alveolar ducts
- alveolar sacs
4
Q
Blood
A
- pulmonary artery and branches = deoxygenated
- pulm arteries = deoxygenated
- pulm veins = oxygenated
- systemic arteries = oxygenated
- systemic veins = deoxygenated
5
Q
Lungs
A
- pleura membrane protects
- intrapleura fluid inbetween
- lungs not symmetrical
- left lung = 2 lobes
- right lung = 3 lobes
6
Q
Ventilation
A
- purpose = bring ambient air into close contact with pulonary capillary blood to exchange O2/CO2
- flow through tubule structures is directly proportional to the pressure difference to the ends of the tubes and inversely proportional to the resistance of flow from radi and length of tubes
- when atmo pressure is greater than alveolar pressure, air flows into lungs
- intrapleural pressure always = 3mmHg less than atmospheric pressure
7
Q
Ventilation Equation
A
(Alveolar pressure - atmospheric pressure) / resistance to airflow
= force promoting air flow
- 1 mmHg is all needed to move normal breath
8
Q
Events of Inspiration
A
- diaphragm and inspiratory inercoastals contract
- thorax expands
- interpulmonary pressure becomes more subatmospheric
- increase transpulmonary pressure
- lungs expand
- alveolar pressure becomes subatmospheric
- air flows into alveoli
- *BOYLE’S LAW**
9
Q
Lung Compliance
A
- measure of stiffness of the lung
- compliance is the difference in lung volume/ transpulmonary pressure difference
- as trasnpulmonary pressure increases, lung pressure increases
- increase compliance = lung is less stiff = easier to inflate
- if decrease compliance, takes greater change in pressure
10
Q
Spirometer
A
- measures breathing
- nose clip
- breath normal, then big in and big out
- tidal volume = 500 ml in average person at rest
- dead space = air that does not participate in gas exchange
11
Q
Gas exchange and transport
A
- O2 moves from alveolar gas to capillary down concentration gradient
- CO2 moves from capillary blood into alveolar gas down its concentration gradient
- gas exchange ratio 200/250 = 0.8
12
Q
Partial Pressures of Gas
A
- diffuse capacity of the lung for CO2 is higher than for O2, so smaller partial pressure is enough
13
Q
Gas Exchange
A
- as blood passes along pulmonary capillary, PO2 rises until is same as alveolar PO2
- rises pretty rapidly
- usually reaches alveolar PO2 1/4 way through capillary
- systemic venous PO2 is starting point because it is what is ended within systemic circulation and therefore what it starts with in the pulmonary system
- blood flow and ventilation needs to match to keep correct amounts of air/O2 in the body to avoid too much CO2
- O2 is transported via blood bound to hemoglobin
- O2 atoms bind reversibly to iron
14
Q
Venous pressures
A
- PO2 = 40 mmHg
- PCO2 = 46 mmHg
15
Q
Arterial pressures
A
- PO2 = 100 mmHg
- PCO2 = 40 mmHg
