respiratory system Flashcards
Each lung is surrounded by two layers of serous membrane known as pleurae. These are:
__________ pleura; covers the surface of the lung
__________ pleura; lines the thoracic wall
This fluid assists breathing movements by acting as a/an
1) VISCERAL PLEURA
2) PARIETAL PLEURA
lubricant
The space in between is called the ____________ cavity and it is filled with ___________ fluid.
This fluid assists breathing movements by acting as a ________________.
1) PLEURAL CAVITY
2) PLEURAL FLUID
Airways from the nasal cavity through the terminal bronchioles are called the __________________
zone.
The function of this zone is to _____________ and ______________ the air.
Is there gas exchange in this zone? ______
1) CONDUCTING ZONE
2) WARM AND MOISTEN
3) NO
The respiratory zone contains ______________ where gas is exchanged. This zone consists of the
______________ bronchioles, ___________ ducts and _____________ sacs
1) ALVEOLI
2) RESPIRATORY BRONCHIOLES
3) ALVEOLAR DUCTS
4) ALVEOLAR SACS
Name the three types of cells in the alveolus:
CELL I, ALVEOLAR MACROPHAGES, CELL II
. ______________; simple squamous epithelium
2. ______________; removes debris and microbes
3. ______________; secretes surfactant. Surfactant (decreases or increases) surface tension which
prevents the alveoli from collapsing.
CELL I
ALVEOLAR MACROPHAGES
CELL II
decrease
The thin respiratory membrane consists of the _____________________ epithelium and the
_____________ membrane of both the alveolus and the capillary
SIMPLE SQUAMOUS
BASEMENT
The relationship between pressure and volume
boyles law
Increased volume leads to
decrease pressure
decrease volume leads to
increase pressure
Intrapulmonary pressure __ during inspiration
decreases
What pressure is always negative and helps to keep the lungs inflated
intrapleural pressure
If transpulmonary pressure equals zero, what will happen to the lungs
collapse
List the factors that affect pulmonary gas exchange
surface area of the membrane
concentration gradient
thickness of the membrane
the distance of diffusion
List the two ways oxygen is transported in the blood
- physically dissolved within the blood plasma
- bound to hemoglobin within RBCs
When oxygen is loaded onto hemoglobin in the lungs, hemoglobin is called ?, and when oxygen is unloaded from the hemoglobin at the tissues, it is called ?
oxyhemoglobin
deoxygemoglobin
What are the three ways that carbon dioxide is transported within the blood?
- physically dissolved within the blood plasma
- bound to hemoglobin within RBCs
- as bicarbonate (HCO3-)
CO2 binds with water to form _________
the catalyst for the formation of carbonic acid is ____
carbonic acid dissociates into ______ and ______
carbonic acid
carbonic anhydrase
hydrogen ions and bicarbonate ions
when bicarbonate ions move out of the red blood cells, _____ ions move in. this is known as the _______
chloride,
chloride shift
Even the most forceful exhalation leaves air in the lungs, this is called the (_______ _______), and is needed to (______ ______ ______).
Residual volume;
keep alveoli open
Why is the rate of CO2 exchange roughly equivalent to that of O2 despite its less steep pressure gradient
CO2 is more soluble in water than is O2.
Surfactant ? surface tension, which prevents the alveoli from collapsing.
increase
is an event necessary to supply the body with O2 and dispose of CO2?
pulmonary ventilation
internal respiration
The alveolar and pulmonary capillary walls and their fused basement membranes are called the:
Respiratory Membrane
What determines the direction of respiratory gas movement?
the partial pressure gradient of the gases
The pressure in the pleural cavity is called the:
intrapleural pressure
Approximately 98.5% of oxygen is transported bound to:
the iron atom in the heme of hemoglobin
what provide the greatest surface area for gas exchange?
alveoli
The walls of the alveoli are composed of two types of cells, type I and type II. The function of type II is to ________.
to secrete surfactant
The air left in the lungs after a strenuous exhale is called the:
Residual Volume (RV)
The lung volume that represents the total volume of exchangeable air is the ________.
vital capacity
Air moves into the lungs when the pressure inside the lungs is:
less than the pressure in the atmosphere
Simple squamous epithelium comprising the wall of an alveolus
Permit gas exchange by simple diffusion Secrete angiotensin converting enzyme (ACE) that helps to regulate blood pressure
Type 1 cells
(secrete surfactant
Type 2 cells
Surfactant does what to the surface tension of water molecules so that the alveoli don‟t collapse after each expiration
decrease
connect adjacent alveoli Allow air pressure in lung to equalize Provide alternate air routes for alveoli that may have collapsed due to disease or injury
Alveolar pores
constantly “sweep” the surfaces of alveoli to keep them sterile; as mucus is moved upward through the air passageways, dead and aged macrophages are carried upward
Alveolar macrophages
surround and support the alveoli
Elastic fibers
Breathing, or pulmonary ventilation, consists of two phases
– air flows into the lungs
– gases exit the lungs
Inspiration
Expiration
Respiratory pressure is always described relative to
atmospheric pressure
Negative respiratory pressure
Positive respiratory pressure
is less than Patm
is greater than Patm
pressure within the alveoli
Intrapulmonary pressure
pressure within the pleural cavity
Intrapleural pressure
Intrapulmonary pressure always eventually ? itself with atmospheric pressure
equalizes
Intrapleural pressure is always ? intrapulmonary pressure and atmospheric pressure
less than
Two forces act to pull the lungs away from the thoracic wall, promoting lung collapse
Elasticity of lungs causes them to ?
Surface tension of alveolar fluid draws alveoli to their ?
assume smallest possible size
smallest possible size
elasticity of the chest wall pulls the thorax outward to enlarge the lungs
Opposing force –
Lung Collapse will occur if: Any condition (like chest wound) that equalizes ?
? intrapulmonary and intrapleural pressures that keeps the lungs from collapsing.
Pip with intrapulmonary or atmospheric pressure causes immediate lung collapse.
the difference between
A mechanical process that depends on volume changes in the thoracic cavity
Pulmonary ventilation
with Pulmonary ventilation Volume changes lead to ?which lead to the flow of gases to
pressure changes
equalize pressure
the relationship between the pressure and volume of gases P1V1 = P2V2
Boyle’s law
Look at Boyle’s Law this way:
A gas always ? its container
Large container, lots of space between gas molecules causes ?
Smaller container, gas molecules are closer together
fills
less pressure
higher pressure
when inspiration occurs The diaphragm and external intercostal muscles (inspiratory muscles) does what?
contract and the rib cage rise
with inspiration The lungs are stretched and intrapulmonary volume ?
Intrapulmonary pressure ?
Air flows into the lungs, down its pressure gradient, until ?
increases
drops below atmospheric pressure (1 mm Hg)
intrapleural pressure = atmospheric pressure
with expiration Inspiratory muscles ? and the rib cage ? due to gravity
Thoracic cavity volume ?
Elastic lungs recoil passively and intrapulmonary volume ?
Intrapulmonary pressure does what?
Gases flow out of the lungs down the pressure gradient until ?
relax, descends decreases decreases rises above atmospheric pressure (+1 mm Hg) intrapulmonary pressure is 0
External respiration
Oxygen ? and CO2 ? the lungs
Blood ? oxygen and ?
Enters, leaves
gains, loses Co2
Factors influencing the movement of oxygen and carbon dioxide across the respiratory membrane
Partial pressure gradients and gas solubilities (see below)
Matching of alveolar ventilation and pulmonary blood perfusion (see below)
Structural characteristics of the respiratory membrane (see below)
the amount of gas reaching the alveoli
Ventilation
the blood flow reaching the alveoli
Perfusion
The role of Hb in oxygen transport:
Each Hb molecule binds ? in a rapid and reversible process .
The hemoglobin-oxygen combination is called?
Hemoglobin that has released oxygen is called ?
four oxygen atoms
oxyhemoglobin
reduced hemoglobin
Transport of Oxygen – Hb:
when all four hemes of the molecule are bound to oxygen is called?
when one to three hemes are bound to oxygen is called?
Saturated hemoglobin
Partially saturated hemoglobin
The rate that hemoglobin binds and releases oxygen is regulated by:
temperature,
blood pH, PCO2,
and the concentration of BPG (an organic chemical) These factors ensure adequate delivery of oxygen to tissue cells
