Respiratory System Flashcards
Singultus
hiccups
Pleural fluid function
holds lungs tight against thoracic cavity wall in partially inflated state
Larynx (structure and function):
tube composed of 3 cartilages
*Thyroid cartilage and cricoid cartilage are made of hyaline cartilage (protect glottis and entrance to the trachea)
*Epiglottis is made of elastic cartilage
The three functions of the larynx are:
1. To provide a patent airway (open and clear)
2. To act as a switching mechanism to route air
and food into the proper channels
* If food or liquids touch the vocal folds it sets off
coughing reflex
3. To function in voice production (houses the
vocal cords)
*Thyroid cartilage and cricoid cartilage are made of ________ _______(protect glottis and entrance to the trachea)
*Epiglottis is made of ______ ________
hyaline cartilage; elastic cartilage
thyroid cartilage elongates in response to ________
androgens
Chondrolaryngoplasty
surgery to reduce size of adam’s apple
-During normal breathing, the vocal cords are ____ and the glottis is a ______ ______
-During swallowing, the ___ ____ ____ and ______ close off the glottis
relaxed; triangular slit
false vocal cords (vestibular fold) ; epiglottis
Speech – intermittent release of expired air while
opening and closing the _____
* Loudness – increase loudness by increasing the
____ at which the air rushes across the ______
* Pitch – changed by changing _____ of the _______
* The _____ resonates, amplifies, and enhances
sound quality
* Sound is “shaped” into language by action of the
pharynx, tongue, ____, and _____
glottis
force; vocal cords
tension; vocal cords
pharynx
soft palate; lips
allows trachea to adjust its diameter and change the resistance to airflow as needed
Band of smooth muscle – (trachealis muscle)
mucociliary escalator
Mucous cells and mucous glands produce mucus that bathes exposed surfaces, traps smaller particles
- in bronchi, and bronchioles
Cilia sweep debris trapped in mucus upwards, toward the pharynx
*Can be coughed out or swallowed and carried to the stomach to destroy any microorganisms in the mucus
______ _______ engulf small particles that
reach lungs
Alveolar macrophages
What type of epithelium lines the respiratory tract in bronchi and bronchioles?
Ciliated columnar epithelial cell (mucociliary escalator)
Respiratory tract =
conducting zone + respiratory zone
Conducting zone:
nasal cavity down to the terminal bronchioles; makes
up most of the respiratory tract. Moves air and prepares it for gas exchange (moistens, warms and filters)
Respiratory zone:
Respiratory bronchioles & alveoli; site of O2 and CO2 exchange with blood
As bronchial tree branch and become smaller, they have less cartilage and eventually have a complete layer of ___ ____ _____ (bronchioles)
circular smooth muscle
Bronchioles
– Lack cartilage support and mucus-producing cells
– Dominated by smooth muscle
– Changes in the diameter control the resistance to airflow and distribution of air
Bronchitis
inflammation of smooth muscle in bronchioles
Throughout airways CELL TYPE (epithelium) CHANGES:
– Bronchi (1, 2, 3):
– Larger bronchioles:
– Smaller bronchioles:
– Terminal bronchioles:
- Respiratory Zone (alveoli):
– Bronchi (1, 2, 3): Pseudostratified ciliated columnar
– Larger bronchioles: Ciliated simple columnar epithelium
– Smaller bronchioles: Ciliated simple cuboidal epithelium
– Terminal bronchioles: Nonciliated simple cuboidal epithelium
- Respiratory Zone (alveoli): Simple squamous epithelium
Bronchi (1, 2, 3) epithelium:
Pseudostratified ciliated columnar
Larger bronchioles epithelium:
Ciliated simple columnar
Smaller bronchioles epithelium:
Ciliated simple cuboidal
Terminal bronchioles epithelium:
Non-ciliated simple cuboidal
Alveolar sac =
two or more alveoli that share a common opening (lead into alveolar duct)
- Respiratory Zone (alveoli) epithelium:
Simple squamous
Alveolus:
cup shaped, air-filled
outpouching lined with simple
squamous epithelium
-Surrounded by capillaries / elastic
fibers
type 1 cell of alveolar wall
Most prevalent – simple squamous epithelial cells line alveolar wall; site of gas diffusion
type 2 cell of alveoli
surfactant-secreting cells
Gas exchange occurs at the ____ _____.
Very short distance between the alveolar air and the
blood allows for ____ _____ of gases.
respiratory membrane; rapid diffusion
capnia:
CO2 in the blood
What prevents air-filled alveoli from collapsing?
Surfactant
Surfactant
- Oily secretion (much like detergent or soap)
- Secreted by Type II cells in alveoli
- Contains phospholipids and proteins
- Coats alveolar surfaces and reduces surface tension
- Prevents lungs from collapsing at the end of expiration
Surfactant coats alveolar surfaces and _____ surface tension
reduces
Alveoli act like balloons…takes some effort
to inflate them due to:
LaPlace’s Law for Surface Tension
Pressure = 2(Tension)/radius or P= 2T/r
Without surfactant:
the pressure/surface tension would be greater in smaller alveoli because they have a smaller radius, and would have a tendency to collapse
Most babies have enough to keep alveoli from collapsing by around the ____ week of gestation
* Very premature infants will likely need _____ ____ _____
34th; surfactant replacement therapy
Respiratory Distress Syndrome
Difficulty breathing due to collapse of alveoli
Lung Compliance
Measure of how easily the lungs expand. Related to:
Connective tissue of lungs
Level of surfactant production
Mobility of the thoracic cage
High Compliance:
normal healthy lung: elastic connective tissue and adequate surfactant. Higher the compliance – easier to fill and empty the lungs.
Low Compliance:
respiratory disorders: reduced surface tension or damaged elastic tissue
Premature babies -lack adequate surfactant
Emphysema – destroys connective tissue
Arthritis / skeletal disorders – impaired articulations
Emphysema
destroys lung connective tissue, makes for low lung compliance, harder/more resting energy demand to breathe
lobar bronchus:
secondary bronchus (after main/primary bronchus, before tertiary/segmental bronchus)
segmental bronchus:
tertiary bronchus: after lobar, before bronchioles
Each tertiary bronchus supplies one bronchopulmonary segment
Intrapleural pressure
Pressure in pleural cavity between visceral and parietal pleura. Pleural fluid causes surface of each lung to stick to inner wall of the chest and superior surface of
diaphragm. Elastic fibers around each alveolus not strong enough to oppose fluid bond.
Muscular pump
(diaphragm – intercostal muscles) is needed to create pressure gradients
Asthma
Resistance to air flow is impacted by the diameter of the tubes through which air is flowing
Boyle’s Law
***inverse relationship between pressure and volume (think air in lungs)
- The relationship between the pressure and volume of gases
- Important in dynamics of pulmonary ventilation; inspiration / expiration
- If: (at a constant temp)
– decrease volume of container, P rises
– increase volume of container, P will fall P=1/V
ELASTIC RECOIL
the rib cage returns to it’s original position and
the diaphragm relaxes, elastic recoil of tissues that are stretched during inhalation
Tidal volume (VT)
normal air taken in during respiratory cycle (~
500 mL in and 500 mL out)
Inspiratory reserve volume (IRV)
amount of air you can take in
above tidal volume (1900 mL female, 3300 mL male)
Inspiratory capacity
TV + IRV (tidal volume plus inspiratory reserve volume) (total inspiratory volume)
Expiratory reserve volume (ERV)
amount of air you can voluntarily
expel after quiet respiratory cycle
Residual volume (RV)
amount of air in lungs after maximal exhalation
Vital capacity
ERV + TV + IRV
Functional residual capacity (FRC)
amount of air remaining in your
lungs after a quiet respiratory cycle (ERV + RV)
Total lung capacity
total volume of the lungs. Vital capacity and residual volume
pneumothorax
air collects between lungs and the chest wall. The air accumulation can apply pressure on the lung and heart and make the lung collapse.
treatment of pnemothorax
trapped air is removed by using a chest tube
Secondary spontaneous pneumothorax
lung collapse in the presence of other underlying conditions:
Chronic obstructive pulmonary disease
Tuberculosis
Pneumonia
Asthma
CF
Lung cancer
Interstitial lung cancer
how can the lung collapse? (2 ways)
Penetrating chest wound
Secondary spontaneous pneumothorax
External Ventilation:
Includes all processes involved in exchanging O2
and CO2 with the environment
1. Ventilation (breathing)
2. gas exchange between alveoli and blood
Internal respiration
Result of cellular respiration
Involves the uptake of O2 and production of CO2 within individual cells
myoclonus
involuntary twitching of muscles–in the diaphragm results in hiccups (singultus)
phrenic nerve
controls thoracic diaphragm. upon its myelination, fetuses can hiccup in utero
Dalton’s Law:
Partial pressure of an individual gas in a
mixture of gases is the percentage of the gas in the
mixture times the total atm pressure of the mixture of
gases
Henry’s Law:
The solubility of a gas in a liquid is proportional to the pressure of that gas above the liquid
-Range of PCO2 in the blood is about _____ mm Hg
-Range of PO2 in the blood is considerable (____ mm Hg)
40-45
40–104 (deoxygenated vs oxygenated)
Differences in partial pressures of a gas facilitate _____!!
movement (Dalton’s law) (high pressure to low pressure): Differences in partial pressures of a gas across biological membranes facilitate diffusion
The amount of gas that will dissolve in a liquid also
depends upon its solubility:
-Carbon dioxide is the ______ (2.62 ml/dL; PC02 = 40 mm Hg
-Oxygen is _____ as soluble as carbon dioxide (0.29 ml/dL; P02= 100 mm Hg)
-Nitrogen is ____ in plasma (1.25 ml/dL; PN2= 573 mm Hg)
most soluble
1/20th
practically insoluble
vesico
pertaining to the urinary bladder
Due to differences in partial
pressures of O2 and CO2:
-P02 is _____ in alveoli than in capillary…02 diffuses into _____
-PCO2 is _____ in capillary than in alveoli…CO2 diffuses into ____
higher; capillary
higher; alveoli
oxyhemoglobin
The hemoglobin-oxygen combination (HbO2) (4 O per Hb)
deoxyhemoglobin
(reduced hemoglobin (HHb)) …
Hemoglobin that has released oxygen
Oxygen in the blood is bound to hemoglobin (_____%)
Approximately ____% is dissolved in the water in plasma
ATP generated ______ in the RBC
98.5
1.5
anaerobically
Positive cooperative binding
When one molecule of O2
binds this causes a
conformational change
making other heme units
more accessible to O2
Environmental Factors Affecting Hb Saturation:
– Arterial PCO2 of blood (higher PCO2 shifts right.)
– Blood pH (lower pH shifts right)
– Temperature (higher T shifts right)
– Metabolic activity within RBCs (increased BPG shifts right)
Bohr effect
the result of pH on hemoglobin-saturation curve
– Caused by CO2: At the tissue (where CO2 is high) CO2
diffuses into RBC
* Series of reactions occur
* Hydrogen ions diffuse out of RBC = lowers pH
Shift curve to the left = _____ affinity
of Hb for oxygen (less delivery of 02 to
tissues; Hb holds on to oxygen)
Shift curve to the right = ______ affinity
of Hb for oxygen (more delivery of 02
to tissues; oxygen unloaded from Hb)
higher; lower
Carbon dioxide is transported in the blood in three
forms:
-Dissolved in plasma
-Chemically bound to hemoglobin as carbaminohemoglobin (CO2 binds to different area on Hb; binds to exposed amino groups)
-Bicarbonate ion in plasma (HCO3–)
Carbon dioxide is transported in the blood in three
forms:
-Dissolved in plasma – _____%
-Chemically bound to hemoglobin – ______% is carried in RBCs as _______ (CO2 binds to different area on Hb; binds to exposed _____ _____)
-Bicarbonate ion in plasma – _____% is transported as bicarbonate (HCO3–)
7 to 10%
20% ; carbaminohemoglobin; amino groups
70%
Haldane Effect:
Describes how oxygen concentrations determine hemoglobin’s affinity for C02
. Binding of oxygen to hemoglobin displaces CO2, reduces Hb’s affinity for CO2
Carbon dioxide diffuses into RBCs and combines with water to form _______ (H2CO3), which quickly dissociates into ______ and _______ (HC03-)
In RBCs, ______ reversibly catalyzes the conversion of carbon dioxide and water to carbonic acid (unstable)
carbonic acid; hydrogen ions; bicarbonate ion
carbonic anhydrase; carbonic acid
Hb-O =
Hb-H=
CO2-Hb=
H2C03=
HC03- =
Hb-O = oxyhemoglobin
Hb-H= deoxyhemoglobin
CO2-Hb= carbaminohemoglobin
H2C03 = carbonic acid
HC03- = bicarbonate ion
Central (in medulla oblongata) and peripheral chemoreceptors (aortic arch, carotids) sense ________
changes in pH and PO2;
When pH of blood gets too low (too acidic), respiration rate ______
INCREASES….Rid the body of excess CO2 faster!!
_____ regulate respiratory muscles
Nuclei in the medulla oblongata (and pons)
Hypercapnia:
increase in arterial PCo2
Hypoventilation is a common cause of hypercapnia
Abnormally low respiration rate
Allows CO2 buildup in blood
Stimulates chemoreceptors to INCREASE respiration rate (to rid the body of excess CO2)
Hypocapnia:
decrease in arterial PCo2
Excessive ventilation, hyperventilation, results in abnormally low PCO2 (hypocapnia)
Stimulates chemoreceptors to decrease respiratory rate
CFTR
Cystic Fibrosis Transmembrane Conductance
Regulator
Transmembrane, integral membrane protein
When defective leads to disrupted chloride secretion, sodium
absorption and water transport across epithelium
Movement of chloride also influences movement of water down
the osmotic gradient, this helps keep the mucus thin and freely
moving
The CFTR protein also regulates the function of sodium ion
channels; Na ions follow to help balance the electrical charge
What are the 2 ways substances
cross an epithelium?
Transcellular
Paracellular
What screening should have helped
detect CF identified in this women?
Newborn Screening
What is a pilocarpine sweat test?
Pilocarpine is a cholinergic agent – mimics the effects of acetylcholine,
stimulates muscarinic receptors on sweat glands
high Cl- = CF
What structures in the lungs were affected
if wheezing and rales heard? What are rales?
Respiratory zones / terminal bronchioles / smooth muscle / alveoli
Rales are clicking, rattling, or crackling noises that
are heard using a stethoscope (auscultation). One
or both lungs can make this noise during
inhalation.
What is bronchiectasis?
- Abnormal widening of the airways due to recurrent inflammation and infection
- Extra mucus pools in the enlarged areas
- Bacterial overgrowth leads to lung infections
- Cilia can’t clear the airways of debris and extra mucus, airway obstruction occurs
CF Lung:
impaired Cl and bicarbonate secretion, alters
osmotic gradient, prevents fluid secretion, airway surface liquid (ASL) gets dehydrated, mucous hard to clear providing opportunity for bacterial growth
What 3 intracellular organelles do you think are
responsible for the CF mutations?
Nucleus – DNA
ER
Golgi
What are the names of the cells involved in CF/with CFTR?
- Ionocytes –discovered in 2018 at Harvard, expresses high levels of CFTR,
single cell sequencing technology. Helps better target therapies - Secretory cells
- Basal cells
- Ciliated cells
What were 3 types of therapies that could be used to treat CF?
RNA Therapy
Gene Editing (basal cells)
Cell based therapy – remove cells, edit, redeliver
