Respiratory System Flashcards
What is the number one function of respiration?
Gas Exchange
What are the other functions of respiration besides gas exchange?
- Receptors for smell
- Filter, warm, and moisten incoming air
- Some structures can Produce sounds (phonation)
- Eliminate some wastes other than CO2
(water vapor, alcohol, ketones)
What is respiration?
Exchange of gases between the atmosphere, blood, and body cells
What are the three basic processes of respiration?
- Pulmonary ventilation: moving air in/out
- External Respiration: Gas exchange between air and blood
- Bring air into lungs and exchanges gas w/ blood - Internal Respiration: Gas exchange between blood and cells of body
- The blood circulates through body and exchanges gas w/ cells
Why is oxygen necesssary during respiration?
Oxygen is the terminal electron acceptor in the electron transport chain during the generation of ATP
The respiratory system can be divided into what two parts?
Upper Respiratory Tract: Anything above the larynx
Lower Respiratory Tract: Anything below the larynx
The respiratory system can be divided into what two functions?
Conducting: Airways
Respiratory: Where gas exchange takes place (respiratory bronchioles and alveoli)
What makes up the nose anatomy?
- External Nose
- Internal Nose
- Nasal Cavity
- Paranasal air sinuses
What is the external nose?
The actual nose composed of cartilage, muscles, skin
What makes up the nasal cavity?
- External nose+Internal Nose
- Covered in mucosa
- Nasal Conchae
-Also called turbinate bones,
-As you inhald the air gets swirled around turbinate
bones
-Air contacts more surface area to filter w/ mucus and
warm the air
What does the nose do? (physiology)
- Filter, warm, moisten air
- Olfaction
-olfactory receptors transmit signals through the
cribiform plate of the ethmoid bone - Resonating chamber
-Sounds resonates within chamber of nose
What is the pharynx?
muscular tube made up of constrictor muscles and located posterior to the internal naris and superior to esophagus and larynx
What are the divisions of the pahrynx?
Pharynx has 3 different divisions posterior to internal nose (behind internal naris)
- Nasopharynx
- Oropharynx: behind the mouth
- Laryngopharynx: behind the larynx
What is the epiglottis?
cartilage that covers the glottis (hole that air passes through to trachea) to divide air/food from larynx/esophagus
-When you swallow the epiglottis stays in place but the larynx moves up to close the glottis off
What is the larynx?
the hollow muscular organ forming an air passage to the lungs and holding the vocal cords
What is the larynx made of?
9 types of cartilage
- the thyroid cartilage is the largest
- the cricoid cartilage is a full ring of cartilage that sits below the thyroid cartilage
What is contained within the glottis?
Looking down the glottis you can see the:
- Vestibular folds: false vocal cords
- Vocal folds: true vocal cords
How does voice production occur?
as the vocal cords Abduct (relax) they spread and you make a lower sound as the adduct (contract) they come together and produce higher pitch sound
Where is the trachea located?
Base of larynx to where trachea splits into primary/secondary bronchi
What are the layers of the trachea?
Lumen -> Ciliated Pseudostratified Columnar Epithelium -> Submucosa -> C-shaped Hyaline Cartilage -> Adventitia (connective tissue)
What is significant about the Ciliated Pseudostratified Columnar Epithelium of the trachea?
Contains goblet cells that secrete mucin which when mixed with water form mucus
What is the Mucociliary escalatator?
The cilia of the trache beat upwards in unison. The mucus in the trachea that traps particles is brought upwars and expelled
What is contained within the submucosa of the trachea?
contains mucus glands
What is significant about the cartilage in the trachea?
Keep trachea open and prevent collapse due to pressure changes
C-Shaped
-the posterior side of the cartilage is open to allow for stretch of esophagus
What is the adventitia of the trachea?
connective tissue which anchors the trachea in place
What is Laryngospasm?
If anything other than air touches the tracheal epithelium there is an automatic coughing reflex called Laryngospasm
- Muscles surrounding glottis contract to restrict particles from entering
- Trouble speaking
The trachea ends at the bronchial tree. Walk through the bronchial tree, from beginning to end.
Primary Bronchi -> Secondary Bronchi -> Tertiary Bronchi -> Bronchioles -> Terminal Bronchioles -> Respiratory Broncioles -> Alveolar Ducts and Sacs -> Alveoli
What are the characteristics of the Primary Bronchi?
Right and left bronchi are right before you enter the lungs
What are the characteristics of the Secondary Bronchi?
Called lobar b/c they enter the lobes of the lung
How many lobes are in the right lung and the left lung?
Right - 3
Left - 2
What are the characteristics of the Tertiary Bronchi?
Secondary bronchi break up further into more segments
- 10 segments in the right lung
- 8 segments in the left lung
Where does gas exchange occur in the bronchial tree? What kind of respiration is occuring?
Gas exchange begins in the Respiratory Bronchioles and mainly occurs in the alveoli
What are the characteristics of the alveoli?
Very thin and HUGE surface area for external respiration
What anatomical changes occur to the cartilage in the bronchial tree?
Trachea – C-shaped cartilage
Primary Bronchi - full rings of cartilage
Secondary/Tertiary Bronchi – irregular plates of cartilage
Bronchioles – cartilage gone
What anatomical changes occur to the Smooth Muscle in the bronchial tree?
Smooth Muscle increases as cartilage decreases down the bronchial tree
Allows for bronchodilation vs. bronchoconstriction
-eg. bronchoconstriction to restrict smoke inhalation
What anatomical changes occur to the Epithelium in the bronchial tree?
ciliated pseudostratified + goblet cells (trachea)
ciliated simple columnar + goblet cells
ciliated simple cuboidal + goblet cells
ciliated simple cuboidal
simple cuboidal
simple squamous (alveoli)
What is the Pleurae?
Membrane that covers each lung
-consists of the Visceral, Parietal and Pleural cavity
What is the pleural cavity and what is the function?
space in between parietal and visceral pleura
- filled with pleural fluid that:
1) reduces friction
2) creates pressure gradient
3) compartmentalizes
What is the hilus of the lungs?
indentation on inside of lungs where primary bronchus enters
What are lobules?
collections of alveolar sacs
What are the types of cells that make up the alveolar cell wall? What is their function?
- simple squamous epithelial cell (type I)
- gas exchange - macrophage (dust cell)
- pathogen screening
- also called dust cells - septal cell (produces surfactant)
- surfactant producer
- also called type II pneumocyte
What is the alveolar-capillary membrane?
The respiratory membrane
- Alveolus + Capillary share basement membrane
- CO2 from deoxygenated Blood enters alveolus and O2 enters capillary
What are the components of the respiratory membrane?
- Surfactant (↓ surface tension)
- Type I alveolar epithelial cell
- fused basement membrane
- capillary endothelial cell
How much surface area is contained within each lung?
~70m^2 w/ ~100mL of blood
What supplies blood to the lung?
Pulmonary artery – brings deoxygenated blood from right ventricle to lungs
Bronchial artery – brings oxygenated blood from left ventricle to bronchial tree
-Deoxygenated blood from bronchial tree drains via pulmonary veins
Pulmonary vein – takes blood back to left atrium.
What is the purpose of respiration?
delivering oxygen to cells, getting rid of carbon dioxide
Why do we need to get rid of Carbon dioxide?
Need to get rid of CO2 because it affects pH of body
- pH important for maintaining membrane potential
- Also important for maintaining protein functionality
- Proteins function at specific pH
- Amino acids that form proteins change at different pH’s
What three processes are necessary to accomplish respiration?
- pulmonary ventilation
- external respiration
- Internal respiration
What is inspiration/expiration?
Inspiration is inhalation and expiration is exhalation
How is pressure related to pulmonic ventilation?
A pressure gradient occurs because atmospheric pressure is greater/lesser than intrapulmonic (inside lungs) pressure
-air will flow from high to low pressure
Is inspiration and active or passive process?
Active Process
- Before Inspiration Intrapulmonic pressure = atmospheric pressure (~760 mmHg)
- During inspiration, thoracic cavity expands, increasing volume and lowering pressure (~758 mmHg)
- Air flows in
What law illustrates the process of inspiration?
Boyles Law
P1V1 = P2V2
What is pneumothorax?
Collapsed Lung
-If you have a puncture wound that pierces parietal pleura the thoracic cavity will expand but the lungs will not
What muscles are used to expand the thoracic cavity during inspiration?
The diaphragm and external intercostal muscles during relaxed breathing
Labored breathing uses scalenes and sternocleidomastoid muscles as well
Which nerves innervate the muscles that control inspiration?
Phrenic nerves (C3-5) Thoracic nerves (T1 – T11)
Describe the process of inspiration.
1) Increase thoracic volume
2) Increase pleural volume
3) Decrease intrapleural pressure
4) Increase lung volume
5) Decrease intrapulmonic pressure
6) Air flow into the lungs
Is expiration an active or passive process?
At rest expiration is a passive process lungs have elastin fibers in connective tissue
- Elastic recoil the fibers relax and come back to normal
stretch
- Stop contracting diaphragm and external intercostal
muscles (PASSIVE process at rest)
- Decreasing volume increases pressure and air moves
out
Describe the process of expiration.
1) Decrease thoracic volume
2) Decrease pleural volume
3) Increase intrapleural pressure
4) Decrease lung volume
5) Increase intrapulmonic pressure
6) Air flow out of the lungs
What occurs during forced expiration?
Using internal intercostal muscles to exhale
- When they contract they pull the ribs down and in
- Reducing volume of thoracic cavity forcing air out
Contracting abdominal muscles forces diaphragm up
and reduces thoracic cavity volume
What abdominal muscles are used during forced expiration?
rectus abdominis
abdominal obliques
transversus abdominis
What is compliance?
the ease with which the lungs and thoracic wall can be expanded during inspiration.
What factors affect compliance?
Elasticity + extensibility
- stretch + recoil
surface tension
-surfactant reduces surface tension (easier to expand)
What conditions will decrease compliance?
Any condition that:
destroys lung tissue (emphysema)increases surface tension
fills lungs with fluid (pneumonia)
produces surfactant deficiency (premature birth, near-drowning)
interferes with lung expansion (pneumothorax)
What are the types of volumes related to inspiration/expiration?
Tidal volume
-Air moving in/out at rest
Inspiratory Reserve Volume
-Extra air you can breathe in if your force it
Expiratory Reserve Volume
-Extra air you can breathe out if you force it
Residual Volume
-Leftover air you can’t breathe out
What is anatomical dead space and physiological dead space?
Anatomical Dead Space
-air present in the conduting airways that doesn’t participate in gas exchange
Physiological Dead Space
-Air present in repiratory spaces but not conducting gas exchange
How many mL’s of air is in each of tjhe types of volumes? What is the total?
Tidal Volume (TV) = 500 mL
- ADS = 150 mL
- Alveoli = 350 mL
Inspiratory Reserve Volume (IRV) = 3000 mL
Expiratory Reserve Volume (ERV) = 1200 mL
Residual Volume = 1300 mL
How do you find total lung capacity?
(TV+IRV+ERV+RV)
How do you find vital capacity ?
(TV+IRV+ERV)
How do you find inspiratory capacity?
(TV+IRV)
How do you find functional residual capacity?
(RV+ERV)
How do you find maximum voluntary ventilation?
maximum voluntary ventilation = TV x breaths/minute
How do you find alveolar ventilation rate?
alveolar ventilation rate = alveolar ventilation x breaths/minute
How does Oxygen and Carbon dioxide flow? What is the path?
Both flow down concentration gradient through passive diffusion. From an area of high partial pressure to an area of low partial pressure.
Oxygen:
alveoli -> blood -> interstitial fluid -> body cells
Carbon Dioxide:
body cells -> interstitial fluid -> blood -> alveoli
What is Dalton’s law and how is it related to our study of respiration?
Each gas in a mixture of gases exerts its own pressure as if the other gases were not present.
Relates to the partial pressures of each element present in atmosphere to create overall atmospheric pressure
What is the atmospheric pressure?
760 mmHg
PN2 = 597 mmHg PO2 = 159 mmHg PCO2 = 0.3 mmHg PH2O = 3.7 mmHg
What are the partial pressures of oxygen during External and Internal Respiration?
EXTERNAL RESPIRATION Alveolar Air (104 mmHg) -> Deoxygenated Pulmonary Arterial Blood (40 mmHg) -> Oxygenated Systemic Arterial Blood (104 mmHg) ->
INTERNAL RESPIRATION Interstitial Fluid (40 mmHg) -> Cytoplasm (<40 mmHg)
What are the partial pressures of Carbon Dioxide during External and Internal Respiration?
INTERNAL RESPIRATION
Cytoplasm (>46 mmHg) -> Interstitial Fluid (46 mmHg) ->
EXTERNAL RESPIRATION
Oxygenated Systemic Arterial Blood (40 mmHg) -> Deoxygenated Pulmonary Arterial Blood (46 mmHg) ->
Alveolar Air (40 mmHg) ->
What is External (Pulmonary) Respiration and how does it occur?
Gas Exchange between Alveoli and Pulmonary Blood
Occurs through diffusion 100% of the time
What is the diffusion rate of External (pulmonary) respiration dependent on?
PO2 and PCO2 differences
(Henry’s Law)
total surface area (Fick’s Law)
diffusion distance (Fick’s Law)
breathing rate and depth
What is Internal (Tissue) Respiration and how does it occur?
Gas exchange between Blood and Tissue Cells
-Blood loses O2 (~25% at rest) and gains CO2
Occurs through diffusion 100% of the time
Where does most of the blood go to at rest?
Brain and cardiac muscle
How is oxygen transported?
As oxyhemoglobin (Oxygen+Hemoglobin) in blood
How is Carbon Dioxide transported in blood?
5% dissolved in plasma
5% as carbamino-hemoglobin
90% as bicarbonate ion (HCO3-)
What is the bicarbonate buffer equation?
CO2 + H2O H2CO3 H+ + HCO3-
What is carbonic anhydrase?
enzyme that catalyze the conversion of carbon dioxide and water to bicarbonate and protons or vice versa
What is the relationship between CO2 and H+?
high CO2 means high H+
What is the relationship between and H+ and pH?
high H+ means low pH
So what is the relationship between and CO2 and pH?
high CO2 means low pH
Explain the oxygen dissociation curve.
At Rest the PO2 (~40 mmHg) is higher in the blood so the Oxygen Saturation of Hemoglobin (~75%) is higher
At Exercise there is higher demand for oxygen by skeletal muscle so the PO2 in the blood (~25 mmHg) drops and the oxygen saturation of hemoglobin drops as well (~30%)
What is the most important factor determining % saturation of hemoglobin?
partial pressure of Oxygen
What is the Bohr effect?
pH and PCO2 shifts oxygen dissociation curve
What would cause the oxygen dissociation curve to shift to the right? What does this mean?
pH Decrease
PCO2 Increase
Temp Increase
BPG
The shift to the right means you can deliver oxygen to the tissues better because the oxygen saturation of hemoglobin decreases
What would cause the oxygen dissociation curve to shift to the left? What does this mean?
pH Increase
PCO2 Decrease
Temp Decrease
The shift to the left means you can hold on to oxygen better because the oxygen saturation of hemoglobin increases
