Final Exam Flashcards
Where and how much CO2 is formed
1/3 from pyruvate and 2/3 from citric acid cycle
Why are those with diabetic ketoacidosis have very labored exaggerated breaths
they’re trying to get rid of as much CO2 as possible
Acidosis
pH is in normal range
Functions of the lung
provides O2 and releases CO2, communication, defends against microbes, influences arterial concentrations of chemical messengers, traps and dissolves clots
How do the lungs defend against microbes
ciliated lining and mucus found within the respiratory tract
How do the lungs influence arterial concentrations of chemical messengers
receiving some messengers from pulmonary capillary blood and producing and adding others to the blood, lung endothelial cells have angiotensin converting enzyme
How do the lungs trap and dissolve clots
increase the production of plasma through plasminogen activator found within lung capillary epithelial cells, plasma will lyse fibrin and dissolve clots
Tidal volume
amount of air inhaled or exhaled in one breath during relaxed, quiet breathing; 500ml
Inspiratory reserve volume
amount of air in excess of tidal inspiration that can be inhaled with maximum effort; 3,000ml (TV +3L)
Expiratory reserve volume
amount of air in excess of tidal expiration that can be exhaled with maximum effort; 1,200ml
Residual volume
amount of air remaining in the lungs after maximum expiration to keep alveoli inflated between breaths and mix fresh air on the next inspiration; 1,200ml
How are the lungs always inflated
the fluid between the visceral pleura and parietal pleura will cause them to stick together and keep the lungs inflated
Pleuritis
membranes of the lungs come in contact with each other leading to inflammation
Vital capacity
amount of air that can be exhaled with maximum effort after maximum inspiration; 4,700ml (TV+IRV+ERV)
Inspiratory capacity
maximum amount of air that can be inhaled after a normal tidal expiration; 3,500ml (TV+IRV)
Functional residual capacity
amount of air remaining in the lungs after a normal tidal expiration; 2,400 ml (RV+ERV)
Total lung capacity
maximum amount of air the lungs can contain; 5,900ml (VC+RV)
Pharynx
funnels things to respiratory and digestive tract
Parts of the pharynx
nasopharynx, oropharynx, laryngopharynx
Nasopharynx
right behind the nasal cavity
Laryngopharynx
right above the separation of respiratory and digestive tract
Epiglottis
cartilaginous flap of tissue that covers the glottis when we swallow
Diaphragm
separates the thoracic and abdominal cavity, dome shaped skeletal muscle
What happens when the diaphragm contracts
it flattens and pulls the lungs in, naturally drawing air into the lungs due to change in pressure
What makes the trachea sturdy
c shaped cartilaginous rings, on the posterior end the cartilage is thin
Respiratory pathway from trachea to capillaries
trachea leads to the primary bronchi, then a right and left primary bronchus, the right primary bronchus separates into three secondary bronchi, the left primary bronchus separates into two secondary bronchi. secondary bronchi brand into tertiary bronchi and continually until they become so small in diameter they lead into alveolar ducts and eventually into alveolar sacs
What determines how many secondary bronchi the primary bronchi will split into
dependent on how many lobes of the lung there are
Cardiac notch
the heart will sit more to the left than the right in the heart and the apex of the heart will sit in the notch
Mediastinum
tissue in the middle where the esophagus and heart sits
Alveolus
bundle of alveoli forming a bundle shaped structure, also referred to as acinus in other tissues such as the pancreas, made of simple squamous epithelial tissue
What surrounds an alveoli
capillary net made of simple squamous epithelial cells and smooth muscle called bronchiole smooth muscles
Asthma
muscles constrict within in the bronchioles when they are not supposed to
COPD
chronic obstructive pulmonary disease, failure in expiration of air, air remains trapped in the lungs
Albuterol
act as agonists to beta 2 adrenergic receptors to act like epinephrine and relax bronchiole smooth muscles
How many alveoli per lung
350 million
What is the surface area of lung tissue is exposed to air when take in a maximum possible breath
size of a tennis court
Alveolar septum
connective tissue amongst the alveoli
Elastin
primary protein found within alveoli septum
What happens when you destroy alveolar walls
you destroy septal tissue leading to alveoli meshing together and losing surface area, found within COPD
Chronic bronchitis
inflammation of respiratory passage way, chronic mucus production and secretion, has to be present for 3 months out of the year for two consecutive years, can be caused by smoking
Primary emphysema
inherited form, deficiency in alpha-1-anti-tripsin whose job is to suppress activity of protease enzymes such as elastase
Secondary emphysema
caused by smoking, supresses activity of protease enzymes such as elastase
What causes alveoli becoming hyper inflated
air trapping (by asthma, chronic bronchitis, or emphysema), the air just circles around the alveoli
Recoil force in alveoli
happens when you let air out, the hydrogen bonds caused by cohesion and adhesion (surface tension) is a force that alveoli have to overcome in order to expand but also is the force that causes recoil causing the alveoli to “collapse”
Surfactant
changes the surface tension of alveoli, equalizes it between such that the pressure will be the same between alveoli with different radii
Respiratory distress syndrome
surfactant isn’t being produced, occurs within premature infants, causes the alveoli to collapse
Type 2 alveolar cells
make and produce surfactant
When do type 2 alveolar cells start production
around 24-28 weeks of gestation
When are levels of surfactant levels sufficient
around 28-30 weeks of gestation
Surface tension of alveoli: law of laplace
P=(2T)/r; pressure = 2(surface tension of water)/radius; P will be large when radius is small
Radius of alveoli during development and surfactant
alveoli can develop as a mix of different sizes, without surfactant the pressure would cause air to move from the alveoli with smaller radius to an alveoli with a larger radius leading to the collapse of the alveoli with a smaller radius
Ventilation
exchange of air between atmosphere and alveoli by bulk flow
Bulk flow
something moving from high pressure to low pressure, bulk flow = change in pressure/resistance of tissue , resistance = recoil of alveolar tissue, blood pressure, ect.
What happens after ventilation
there’s gas exchange of O2 and CO2 between air within the alveoli and blood through diffusion
How does O2 move during diffusion
high to low concentration, from alveoli to the RBC
How does CO2 move during diffusion
high to low, RBC to alveoli
How does O2 and CO2 move through the circulatory system
bulk flow
What happens during an inspiration
the external inner costal muscles will contract, ribs spread apart and the sternum is pushed forward, the diaphragm contracts, the thoracic cavity will increase volume while the amount of air inside the lungs at that point is the same leading change in pressure and to bulk flow and ventilation occurs through a passive process
Why is expiration mainly a passive process
change in pressure, elastic recoil of alveoli, no muscles are involved unles syou actively exhale
What happens during expiration
internal intercostal muscles will contract moving the ribs closer pushing the sternum in, the abdominal muscles and oblique muscles push up on the diaphragm
Boyle’s law
describes the changes of lung tissue, air moving from high to low concentration
Pneumothorax
collapse of lung tissue, the lungs can still inflate but there’s a lot of elastic recoil that has to be overcome in order to take a breath in
Tension pneumothorax
there’s an opening made within the thoracic cavity along with the lung tissue, the hole acts as a one way valve for air coming in , inspiration can occur but exhalation will not
What are the signs of tension pneumothorax on an x-ray
there’s a shift of mediastinum and heart and esophagus due to air building up in the thoracic cavity outside the lung tissue
What nerves control inspiration and expiration
intercostal nerve supplies intercostal muscles and nephrenic nerve supplies the diaphragm, the nerves exit from the brain stem: medulla oblongata and pons, the pons will do a lot of control under normal controls automatically
Obstructive sleep apnea
due to the growth of tissue within respiratory pathway near the pharynx and larynx making it hard for the air to enter the trachea, treated by CPAP
How much oxygen on average enters per minute
840ml
How much oxygen on average exits per minute
590ml
How much oxygen on average will diffuse from alveoli into capillary blood per minute
250ml
How much oxygen on average is found within RBC and how much does it mix with and therefore how much oxygen is moved to the left side of the heart
750ml, 250ml, 1000ml
“Deoxygenated” RBC
the 750ml of oxygen found in RBC that are considered “deoxygenated” means that they have less oxygen than oxygenated blood (about 3/4 less)
How much CO2 on average will exit per minute
200ml
How much CO2 on average is within the plasma of oxygenated blood in some form
2600 ml
How much CO2 on average is found within “deoxygenated” blood
2800ml
How will O2 be transported in the body
majority will bind to hemoglobin, through diffusion from RBC to capillaries of cells of the body
Why would O2 dissociate from hemoglobin
to change pH, if the partial pressure of CO2 increases it interacts with water to yield hydrogen ions (CO2 is trapped) and lowers the pH therefore the need for more oxygen is needed
CO2 + H20
CO2+H20 = Carbonate acid with the help of carbonic anhydrase will yield carbonic acid which dissociates to bicarbonate ion (CO-3) and hydrogen ion
How does carbon dioxide move through the body
dissolved in plasma, binds to hemoglobin, as bicarbonate ion in the plasma
CO2 affinity for hemoglobin
will not bind with the affinity of oxygen, binds to carbaminohemoglobin
Chloride shift
bicarbonate will move from the plasma into RBC in exchange for chloride
Which nerves detect low O2 levels and what do they detect
afferent nerve ending of vagus nerve and glossopharyngeal sends info to the brain stem, primarily the medulla oblongata which works with the pons, they detect the concentration of hydrogen ions within the extracellular fluid in the brain
What happens when CO2 is trapped in the lungs and O2 won’t come in
there’s a decrease in partial pressure of oxygen and increase in partial pressure of carbon dioxide
What happens during hypoxia
chemoreceptors will increase firing rate within the afferent nerves, a reflex via the medullary respiratory neurons with the control center as the NOS, leads to an increase of ventilation
Kussmaul inspirations
rapid and exaggerated breathing due to high firing rates of afferent rates found in patients with diabetic ketoacidosis and plasma pH is very low
Sources of hydrogen ions
from CO2 and water, generation of nonvolatile acids from things other than CO2, gain due to loss of bicarbonate acid in diarrhea or other non gastric GI fluids or in the urine
Loss of hydrogen ions
utilization in metabolism of various organic anions, in vomitus, in urine, hyperventilation
How do the lungs and kidneys maintain pH
lungs will control ventilation rate to keep or eliminate CO2, kidneys have a multitude of mechanisms
What’s the balance of bicarbonate and carbonate acid the body wants to maintain
20:1
What happens if you excrete bicarbonate through the kidneys
you retain hydrogen ions increasing the concentration in the plasma decreasing pH
What happens if you reabsorb bicarbonate
you decrease the concentration of hydrogen ions in the plasma and pH increases
What happens any time the kidneys actively contribute new bicarbonate to the plasma
hydrogen ions will be excreted
How is bicarbonate filtered and reabsorbed and what happens after reabsorption
filtered through the glomerulus’s filtration slits, and reabsorbed primarily at the proximal convoluted tubules which then will lead through the ascending limb of the loop of henly and into the collecting duct
How do you get rid of hydrogen ions from the epithelial cells into the lumen of the kidney tubule
hydrogen ATPase pump actively moving hydrogen ions, counter transport with sodium, hydrogen-potassium AtPase pump actively moving hydrogen ions out and reabsorbing potassium
What happens when a hydrogen ion reacts with carbonate acid in the lumen
it can be converted back to water and CO2 leading to the excretion of water
What happens when a hydrogen ion reacts with dibasic phosphate in the lumen
forms a monobasic phosphate which will be excreted
How is glutamate transported from the lumen or blood into the epithelial cell
actively transported through secondary active transport with sodium
What happens to glutamate in the epithelial cell
through a series of reactions it will dissociate into products including bicarbonate and ammonia
What happens to ammonia as soon as it’s made
it will bind to hydrogen ion to form ammonium ion
How does ammonium ion move into the lumen
through counter transport with sodium
What happens to an ammonium ion in the lumen
it will be trapped there due to its charge and be excreted as the ammonium ion
