Respiratory System Flashcards
What makes up the upper respiratory tract?
the nose, the nasal cavity, and the pharynx and associated structures
What makes up the lower respiratory tract?
the larynx, trachea, bronchi and the lungs.
Define respiration
the exchange of gases between the atmosphere, blood and cells.
What are the three basic steps of respiration?
- ventilation (breathing)
- external (pulmonary) respiration
- internal (tissue) respiration
What is the conducting system?
a series of cavities and tubes - nose, pharynx, larynx, trachea, bronchi, bronchiole, and terminal briochioles - that conduct air into the lungs
When talking about the functional divisions of the respiratory system what is the respiratory portion?
-the area where gas exchange occurs - respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli.
What type of cells make up the respiratory region of the nasal cavity?
pseudostratified columnar epithelium with many goblet cells.
True or False: There are goblet cells in the olfactory region.
False. there are cilia but no goblet cells.
What kind of cells are in the nasopharynx?
pseudostratified ciliated columnar epithelium with goblet cells
What type of cells are in the oropharynx?
stratified squamous epithelium
What type of cells are in the laryngopharynx?
stratified squamous epithelium
In what region do you find the pharyngeal tonsils, the palatine tonsils, and the lingual tonsils?
pharyngeal tonsils = nasopharynx
palatine tonsils = post. oral cavity
lingual tonsils = oropharynx
What are the nasal conchae?
shelf-like projections lined with mucous membranes that extend from the lateral wall of the nasal cavity.
What does the nasal conchae divide?
They divide the nasal cavity into groove-like passageways called the superior, middle and inferior meatuses.
What is the function of the nasal conchae and meatuses?
to warm air; trap water molecules on exhalation (moistens)
What are the paranasal sinuses?
the frontal, the sphenoid, the maxillary, and the ethmoidal
What are nasal polyps?
outgrowths of the mucous membranes usually found around the openings of the paranasal sinuses
What is the function of the paranasal sinuses and the nasolacrimal ducts?
to produce mucus and resonate sound and tears.
What is the function of the internal nose structures?
- to warm, moisten, and filter incoming air
- receive olfactory stimuli
- serve as a large, hollow resonating chamber to modify speech sounds
What type of cells are in the nasal cavity?
pseudostratified ciliated columnar with goblet cells
What do the cells in the nasal cavity do?
- warm air due to high vascularity
- mucous moistens air and traps dust
- cilia move mucous towards pharynx
If you are a smoker, what function of the cells in the nasal cavity does not work?
the cilica do not function therefore smokers must cough to release mucus.
What is the pharynx?
a 5 inch muscular tube lined by a mucous membrane that extends from the internal nares to the cricoid cartilage
What are the functions of the nasopharynx, oropharynx and the laryngopharynx?
- passageway for food and air
- resonating chamber for speech production
- tonsil (lymphatic tissue) in the walls protects entryway into the body
Of the three regions of the pharynx, which have respiratory and digestive functions?
the oropharynx and the laryngopharynx
What do the cilia do in the upper respiratory tract vs the cilia in the lower respiratory tract?
the cilia in the upper respiratory tract move mucous and trapped particles down toward the pharynx and the cilia in the lower tract move them up toward the pharynx.
What is the larynx constructed of?
3 single cartilages:
- thyroid cartilage
- the epiglottis
- the cricoid cartilage
3 paired cartilages:
- arytenoid
- corniculate
- cuneiform cartilages
What is the thyroid cartilage commonly called?
Adam’s apple
What does the epiglottis do?
prevent food from entering the larynx
What do the cuneiform cartilages do?
support vocal folds and lateral epiglottis
What is the larynx lining made of?
- superior to the vocal folds is non-keratinized stratified epithelium
- inferior to the vocal folds is pseudostratified ciliated columnar epithelium with goblet cells
What are the false vocal chords called?
the ventricular folds
What are true vocal chords made of?
skeletal muscle and an elastic ligament
What is the purpose of false vocal chords?
pitch, speech and whispering
If pitch is controlled by tension on the vocal folds, what will happen if they are pulled taut by muscles?
a faster vibration which causes a higher pitch
If pitch is controlled by tension on the vocal folds, what will happen if the muscles tension on the folds decreases?
a slower vibration which causes a lower pitch
Why do men have a lower pitch?
Their vocal folds are thicker and longer and so vibrate slower and produce a lower pitch
How do you increase volume of sound?
by pushing air harder through the folds.
How is speech created?
by using the pharynx, mouth, nasal cavity and sinuses to resonate sound
What forms words?
the tongue and mouth
What is the mechanism of whispering?
forcing air through an almost closed rima glottidis which causes no vibration and so no pitch
Where is the trachea located?
from the larynx to T5, anterior to the esophagus
What makes up the trachea?
smooth muscle, c-chaped rings of cartilage and pseudostratified ciliated columnar epithelium with goblet cells
What is the submucosa in the trachea?
loose connective tissue and seromucous glands
What purpose does the trachealis muscle and the CT serve?
they provide support and maintain patency so the tracheal wall does not collapse inward
What is adventita?
composed of loose connective tissue that binds the trachea to other tissues
What is significant about the carina?
widening or distortion usually indicates a carcinoma of the lymph nodes around the region where the trachea divides
How many pleural membranes are there?
2; the parietal pleura and the visceral pleura
Where is the parietal pleura?
on the thoracic wall and superior face of diaphragm
Where is the visceral pleura?
on the the external cavity
What is the purpose of pleural fluid and where is it?
to provide lubrication and surface tension and is located in the pleural cavity
What are the names of the different regions of the parietal pleura?
- costal pleura
- diaphragmatic
- mediastinal
- cervical
What is an open pneumothorax?
occurs when air enters through pleural cavity following a penetrating wound
What is a tension pneumothorax?
occurs when a piece of tissue covers and become a flap over the wound into the thorax
What is a pleural reflection?
occurs when pleura abruptly changes direction from one wall to another.
What is the significance of a pleural reflection?
fluid can accumulate in these recesses
Where is the cardiac notch?
on the left lung
What are the differences between the left and right lung?
the right lung has three lobes separated by two fissures. the left lung has two lobes separated by one fissure and the cardiac notch.
Which lung is smaller and why?
left lung is 10% smaller due to the heart
What lung is shorter and why?
the right lung is shorter due to the liver pushing up on the diaphragm.
What structures lie within the mediastinum?
heart, thymus, esophagus, trachea, large blood vessels
What does the bronchial tree consist of?
the trachea; primary, secondary, and tertiary bronchi; bronchioles; terminal brochioles
The right primary bronchus divides into…
3 secondary (lobar) bronchi
the left primary bronchus divides into…
2 secondary (lobar) bronchi
What lung is more likely to have an aspired object in it and why?
The right lung because it is more vertical, shorter and wider than the left.
How many tertiary bronchi are in each lung?
10
what is a brochopulmonary segment?
a triangular shaped unit of the lungs supplied by the tertiary bronchus
What type of cells are respiratory bronchioles lined with?
simple squamous epithelium
True of False: epithelium changes from pseudostratified ciliated columnar to nonciliated simple cuboidal as it goes deeper into the lungs.
True
What do the sympathetic nervous system and the adrenal glands have to do with the bronchial tree?
They release epinephrine that relaxes smooth muscles and dilates the airway
How many alveoli are in each sac?
2 or more
What are type I alveolar cells?
squamous pulmonary epithelial
What are type II alveolar cells?
septal
What are alveolar macrophages?
dust cells
what happens at the type I alveolar cells?
gas exchange occurs
What do type II alveolar cells do?
secrete alveolar fluid called surfactant
What does surfactant do?
lowers the surface tension of alveolar fluid, preventing the collapse of alveoli with each expiration
What are the layers of membrane that must be crossed during gas exchange in the alveolar-capillary membrane?
- alveolar epithelial wall of type I cells
- alveolar epithelial basement membrane
- capillary basement membrane
- endothelial cells of capillary
How thick is the respiratory membrane?
1/2 (half) microns thick
How much blood can participate in gas exchange at once?
900 ml of blood can participate in gas exchange at once
What is nebulization?
a procedure for administering medication as small droplets suspended in air into the respiratory tract.
What do asthma attacks or allergic reactions do in the respiratory system?
constrict distal bronchiole smooth muscles
What is ventilation-perfusion coupling?
In the lungs vascoconstriction in response to hypoxia diverts pulmonayr blood from poorly ventilated areas to well ventilated areas.
What factors affect pulmonary ventilation?
alveolar surface tension, compliance of the lungs, airway resistance.
Define eupnea?
normal variation in breathing rate and depth
Define apnea
refers to breath holding
Define dyspnea
relates to painful or difficult breathing
Define tachypnea
involves rapid breathing rate
What is coughing?
deep inspiration, closure of rima glottidis and strong expiration blasts air out to clear respiratory passages
What is hiccuping?
spasmodic contraction of diaphragm and quick closure of rima glottidis produce sharp inspiratory sound
In clinical practice, respiration (ventilation) = ___ inspiration and _____ expiration.
one inspiration and one expiration
In a healthy adult, 12 respiratiions/min = ____ litres ___ ___ _____ of lungs while ___ ______.
6; in and out; at rest
What is anatomical dead space?
aka respiratory dead space
-the conducting airways with air that does not undergo respiratory exchange.
Define tidal volume
the volume of one breath
In the average adult how much of the tidal volume reaches the alveoli?
70% or 350ml. the other 30% (150 ml) remains in the anatomic dead space
Define reserve volumes.
amount you can breathe either in or out above that amount of tidal volume
Define inspiratory reserve.
(3100 ml) amount of air taken in during a deep breath, above tidal volume
Define expiratory reserve.
(1200 ml) amount of air that can be forcibly exhaled after a normal inhale
Define residual volume
(1200 ml) air permanently trapped in system/cannot be measured by spirometry
Define minimal volume
amount of air that remains in lungs after some residual volume is forced out when thoracic cavity is opened
Define alveolar ventilation rate (AVR)
(4200 ml/min) volume of air/min that reaches the alveoli
Define FEV1
(forced expiratory volume in 1 second) amount of air forcibly expired in 1 sec with maximal effort following maximal inhalation
Define minute volume of respiration (MVR)
the total volume of air taken in during on minute (tidal volume x 12 respirations per minute = 6000 ml/min)
How does height, gender and age of a person affect lung volumes?
- larger volume - taller, younger and male
- smaller - female, shorter, elderly
What respiratory system structures are in the anatomical dead space?
nose pharynx, larynx, bronchi, bronchioles, terminal bronchioles
Define inspiratory capacity
(3600 ml) tidal volume + inspiratory reserve volume; total inspiratory volume of lungs
Define functional residual capacity
(2400 ml) residual volume + expiratory reserve volume
Define vital capacity
(4800 ml) inspiratory reserve volume + tidal volume + expiratory reserve volume
Define total lung capacity
(6000 ml) sum of all volumes
What are obstructive patterns?
a disease that is characterized by increase in airway resistance that is measured as a decrease in expiratory flow rates
ie. chronic bronchitis and emphysema
What are restrictive patterns?
a disease that is characterized by increase in elastic recoil, a decrease in lung compliance which is measured as a decrease in all lung volumes.
What is Dalton’s law?
each gas in a mixture of gases exerts its own pressure as if all the other gases were not present.
What is Henry’s law?
the quantity of a gas that will dissolve in a liquid is proportional to the partial pressure of the gas and its solubility coefficient (its physical or chemical attraction for water), when the temperature remains constant.
What is the partial pressure of a gas?
the pressure exerted by that gas in a mixture of gases
How much O2 enters the cells at rest?
25%
What are the percentages of oxygen and nitrogen in the air at sea level?
O=21%
N=78%
True or False: The higher the partial pressure of a gas the more it will dissolve in a liquid.
True
What does the rate of diffusion of gases in the lungs depend on?
- partial pressure of gases in air
- large surface area of our alveoli
- diffusion distance (membrane thickness)
- solubility and molecular wight of gases
Why does oxygen diffuse faster?
it is a smaller molecule and has a smaller molecular weight
How much O2 is in 100 ml of oxygenated blood?
20ml
When is a hemoglobin fully saturated?
When all 4 atoms of iron in a hemoglobin carry one oxygen molecule.
How much of the O2 is dissolved in the plasma?
1.5% (.3 ml)
How much of the O2 is carried with hemoglobin?
98.5% (19.7ml)
What is the hemogloblin called once it has picked up the O2?
oxyhemoglobin (HbO2)
When is a hemoglobin partially saturated?
When it only has 1-3 molecules of O2 attached.
What is the most important factor that determines how much oxygen combines with hemoglobin?
the partial pressure of oxygen (PO2)
What is polycythemia?
having more RBCs than you should
True of False: Hemoglobin is 100% saturated with O2 and pO2 of 40mmHg.
False. Hemoglobin is only 75% saturated with O2 at a partial pressure of 40mmHg because only 25% of available O2 unloads from hemoglobin and is used by the tissues.
True of False: The greater the partial pressure of O2, the more oxygen will combine with hemoglobin.
True. it will combine with hemoglobin until the Hb is saturated.
What factors influence the affinity of O2 to Hb?
- Acidity (level of pH)
- partial pressure of carbon dioxide
- temperature
- BPG (2, 3 phosphoglycerate)
How does an increase in temperature affect the affinity of O2 to Hb?
an increase of temperature, due to things like exercise, increases the amount of CO2 and lactic acid in the body (byproducts of energy consumption/creation in the cells) which in turn increases the acidity levels in the body.
How does a low acidic (low pH) environment affect the affinity of O2?
The O2 will split more readily from Hb; called the Bohr effect.
What does a high PCO2 do to the blood pH?
creates a low pH (acidic conditions)
What does a high level of BPG do to the affinity of oxygen?
It causes more oxygen to be released from hemoglobin
What does an increase in acidity do to the affinity of O2?
it decreases the affinity
What happens to CO2 in the body?
CO2 converts to carbonic acid and becomes H+ and bicarbonate ions and lowers pH.
More H+ does what to the pH?
make the pH more acidic
More OH- does what to the pH?
makes it more basic (alkaline)
Why does fetal Hb have a greater affinity for O2 than adult?
because fetal Hb is made of 2 alpha chains and 2 gamma chains while adults have 2 alpha chains and 2 beta chains. gamma chains have a higher affinity for O2.
