cardioresp Flashcards
what is included in the upper resp system
-pharnx
-nasal cavity
-vocal chords
-tongue
-larynx
-esophogous
what is included in the lower resp system
-trachea
-lungs
-diagphram
-bronchus
what are the main components of the respiratory system as a whole (thin parts where you breathe out of)
-layrnx
-pharynx
-nasal cavity
-bronchi
-lungs
-trachea
what Is the trachea
-Known as the “windpipe,” it is the main airway leading into the respiratory system.
-Supported by cartilage rings that prevent the airway from collapsing.
list the three main types of bronchi in the respiratory system
Primary bronchi (lead to each lung), secondary bronchi (lead to each lobe of the lung), and tertiary bronchi (further divide to distribute air deeper in the lungs)
what is the difference between terminal bronchioles and respiratory bronchioles
terminal bronchioles bring to where gas echnage will occur whereas respiratory bronchioles mark the start of the respiratory zone and allow for gas exchange
what is the relationship between Alveolar Ducts, and alveolar sacs
AD branch off of bronchioles, and lead to AS so more amounts of gas exchange can occur
define “anatomic dead space” in the respiratory system
anatomic dead space (VD) is the volume of the conducting airways, approximately 150 mL, which does not participate in gas exchange
why is airway resistance important in the respiratory system
it controls airflow rate, aids in filtration of particles, helps balance internal lung pressures to prevent collapse, and regulates oxygen intake based on activity level
what role does the larynx play in the respiratory system
the larynx directs food and air to the correct passages, protects the airway, and contains the vocal cords for sound production
what happens to cartilage as airways branch deeper into the lungs
supportive cartilage is gradually replaced by smooth muscle, allowing for flexible regulation of airway diameter
describe how lost weight primarily leaves the body and the main byproducts of this process
-cO2 cuz fatty acids and glycerol which are used for energy are converted to co2
-with the rest excreted as water (H₂O) through urine, sweat, and other bodily fluids
what is the respiratory membrane, and where is it located
the respiratory membrane separates the air molecules in the alveoli from the blood in the capillaries, facilitating gas exchange
what is the average thickness of the respiratory membrane
the respiratory membrane is about 0.6 micrometers thick
why is the respiratory membrane so thin
to facilitate the gas exchange through the thin blood capillaries
what is the approximate surface area of the respiratory membrane in a normal adult
the surface area is about 70 square meters, which is roughly the size of one side of a tennis court
how does the large surface area of the respiratory membrane benefit the respiratory system
the large surface area allows for extensive gas exchange, meeting the body’s oxygen demands and facilitating carbon dioxide removal
what does pulmonary ventilation rely on
pressure differences (changes in lung volume)
what is pulmonary ventilation
pulmonary ventilation is the movement of air into and out of the lungs, enabling oxygen intake and carbon dioxide removal.
how does air move in relation to pressure
air moves from areas of high pressure to areas of low pressure, which is essential for inhalation and exhalation
state Boyle’s Law and explain its role in breathing
boyle’s Law states that the pressure of a gas is inversely proportional to its volume. In breathing, when lung volume increases, pressure decreases (inhalation); when lung volume decreases, pressure increases (exhalation)
what happens during inhalation (inspiration) in terms of lung volume and pressure
during inhalation, the diaphragm and intercostal muscles contract, increasing lung volume and decreasing pressure inside the lungs, causing air to flow in
what happens during exhalation (expiration) in terms of lung volume and pressure
increase pressure in the lungs, decrease volume, diagram comes round again and causes intercostal muscles to relax
define lung compliance and explain its significance in breathing
lung compliance is the ability of the lungs to expand for a given change in alveolar pressure. High compliance allows easy lung expansion, while low compliance makes breathing more effortful
describe the pressure difference required for air movement in the lungs
breathing requires a pressure difference between the pulmonary air (within the lungs) and atmospheric air. Inhalation occurs when pulmonary pressure is lower than atmospheric pressure; exhalation occurs when it is higher
what is Boyles law formula
p1v1= p2v2
What pressure changes occur in the thoracic cavity during inhalation and by how much
the volume of the thoracic cavity increases, causing the pressure inside to decrease by 1-2 mm Hg compared to atmospheric pressure, leading air to flow into the lungs
how does the pressure gradient drive air into the lungs during inhalation
the decreased pressure in the lungs (lower than atmospheric pressure) causes air to move into the lungs to equalize the pressure
what is the very thin wall of the respiroty membrane optimized for?
diffusion
what is tidal volume?
the volume of gas inspired or expired with each breathe
how much tidal volume (Vt) per inspiration or expiration at rest
500ml
what is our breathing frequency (Fr) per min
12-16 breaths per minute
what is minute ventilation
gas volume inspired or expired nut not both per minute
what is the formula to find the minute ventilation (Ve)
tidal volume x breathing frequency
what is the Ve (minute ventilation) at rest average
6-8 l/min
what is the Ve (minute ventilation) for max excerise average
180 l/min
what is expiratory reserve volume (ERV)
the amount of forced air that can be exhaled after a normal tidal exhalation (basically how much more air you can force out after you normally relaxed breathe out
what is the correlation ERv has to VC (vital capacity)
because vital capacity is the total amount of air that can be exhaled after a maximum inhalation
how much VC does ERv constitute
25%
what is ridisual volume (RV)
the air remaining in your lungs after forced expiration
what is functional residual capacity (FRC)
volume of gas remaining in the lungs at the end of a quiet exhalation
what is forced vital capacity (FVC)
to exhale as fast and as hard as possible for four seconds
forced expiatory volume in one second (FEV1.0)
the expirorty volume the first second the FVC
what is alveleoer ventilation and whats so important about it
the volume of air that reaches the avaleoi per minute and is the only place where air does gas exchange with the blood
what is the general ormula to calculate aveolar ventiltihation
Va= tidal volume- anatomical dead space
what is the alveolar ventilation equation for rest
VA =(FR)X(VT -VD)
what is the alveolar ventilation equation for max excerise
VA =(FR)X(VT -VD)
what happens to the lung capacity when a person stands vs lays down
laying down decreases capacity and standing increases capacity
what is the reason for lung capacity change when laying down
- Abdominal contents push up against diaphragm
- There is an increase in intrapulmonary blood volume in the horizontal position which decreases the space available for pulmonary air.
what are pulmonary function test norms usually based on
height, age, sex,
what is important to take into account and know in order to construct a proper pulmonary function test norm
the size and make up of the population
what are the problems with the pulmonary function norms
-dont consider the size of subject
-be better to use and account for sitting height and not sanding height
-need to be interred in relation to patients medical history and habits and chest x-ray
what are the two catagories repository disorders can be divided into and their causes
-obstructive disorders (blockage or narrowing of airways causing increased airway resistance,blockage also due to inflammed and edema or bronchial secretion)
-restrictive disorders (damage to the lung tissue, loss of elasticity and compliance limiting expansion of lungs)
what symptoms or illness does obstructive disorders cause
-trouble breathing in and out (decrease in moving air in and out rapdily)
-asthma, bronchitis, emphysema
-decrease (MBC) max bearing capacity)
what symptoms or illness does restrictive disorders cause
-pulmonary fibrosis, pneumonia
-all lung volumes reduced (VC, RV, FRC, TLC)
-lung tissue stiff can’t be expanded very far
what happens to the FEV what you have an obstructive disorder
-it is decrease
-the Fev/FVC is at 40 percent instead of 80 so half as much which means there is obstrrucion to the airways
what happens to the FEV what you have an restricitve disorder
-FEV1.0 and MBC are reduced
-Fev1.0/FVC ratio is 90% or larger meaning it can remain normal as there is no significant obstruction to the airways
what is the circulatory cardiovascular system composed of
-heart
-blood vessels
-blood
function of the circulatory system
-transports essential materials thought the body to cells
-oxegyn
-white blood cells
-nutrients
-signaling molecules
-collects waste from nosy metabolics activity
what two sections is the circulatory divided into
-pulmonary circuit (blood vessels going to and from the lungs)
-systemic circuit (blood vessels going to and from the rest of the tissues of the body)
how does minute ventilation looked like when graphed
increase incrementally linearly
What happens to VE during incremental exercise
Minute ventilation increases linearly with oxygen consumption (V02)
up to: 50–60% for untrained
up to: 75–80% for trained
what does it mean when our VE is graphed linearly
the linear phase means your breathing increases at a steady rate as your body demands more oxygen for energy production
What is the ventilatory threshold
The ventilatory threshold is the point during graded exercise where:
-Minute ventilation increases disproportionately with oxygen consumption
-This occurs due to an increase in carbon dioxide production from lactic acid buffering.
What causes the ventilatory threshold
Lactic acid accumulation during high-intensity exercise
Lactic acid is buffered into C02 increasing the drive to breathe faster to expel it
Why does ventilation increase disproportionately after the ventilatory threshold
CO2 production rises due to anaerobic metabolism.
Rapid breathing helps expel the excess co2
how does VE change before and after the ventilatory threshold
Before the ventilatory threshold: Linear increase with vo2
After the ventilatory threshold: Disproportionate increase due to rising c02 production.
what is the septum in the heart
divides the left and right side
which circuit does the right ventricle pump to
pulmonary circuit
which circuit does left ventricle pump too
systemic circuit
which ventricle is thicker and why
left ventricle pumps blood into the systemic circulation, a higher-pressure system than the pulmonary circulation.
The thicker wall allows it to generate the greater force needed to push blood throughout the entire body
what causes a heart murmur
valve is damaged or does not close properly à blood regurgitates, causing a noise
how is blood flow controlled through the heart
unidirectional valves to keep it flowing one way and not to go back
what is the heart muscle called
myocardium
what happens when some fibres contract run the heart
everything contracts
what part of the heart is ellectically seperepeated form the rest of the heart
atria
What are autorhythmic cells, and what is their function
utorhythmic cells are specialized cardiac cells that:
-Generate spontaneous action potentials.
-Set the rhythm of the heart’s contractions without external stimulation.
What causes autorhythmic cells to fire action potentials spontaneously
-Autorhythmic cells have an unstable resting membrane potential, which slowly depolarizes due to:
-Slow Na⁺ and Ca²⁺ influx.
-Decreased K⁺ efflux.
-When the threshold is reached, they fire an action potential.
How does depolarization spread from autorhythmic cells to other cardiac cells
Depolarization spreads through gap junctions, which:
-Allow ions to pass between adjacent cells
-Ensure rapid and coordinated electrical activity across the heart
What happens in contractile cells during an action potential
-Depolarization: Na⁺ enters the cell rapidly.
-Plateau phase: Ca²⁺ influx maintains depolarization, ensuring sustained contraction.
-Repolarization: K⁺ exits the cell, restoring resting potential
Where is the sinoatrial (SA) node located, and what is its role
The SA node is located in the posterior wall of the right atrium.
It is the natural pacemaker of the heart.
It initiates electrical impulses that set the heart rate (60–100 bpm at rest)
What are internodal pathways, and what do they do
-Spread the electrical signal from the
SA node across the atria.
-Ensure both atria contract simultaneously.
Where is the atrioventricular (AV) node located, and why is it important
The AV node is located in the inter-atrial septum.
It is the only electrical pathway between the atria and ventricles.
It delays the signal by ~0.10 seconds, allowing the atria to contract fully before the ventricles contract
What is the ventricular conduction system, and what is its pathway
-It is the only electrical pathway between the atria and ventricles.
-It delays the signal by ~0.10 seconds, allowing the atria to contract fully before the ventricles contract.
What is the ventricular conduction system, and what is its pathway
- AV bundle (Bundle of His): Transmits the signal from the AV node to the ventricles.
- Right and left bundle branches: Conduct the impulse down the interventricular septum.
3.Purkinje fibers: Spread the depolarization throughout the ventricular muscle cells for coordinated contraction.
What ensures the unidirectional flow of the electrical signal in the heart
The connective tissue separating the atria and ventricles ensures that:
The electrical signal cannot directly pass from the atria to the ventricles.
The signal must pass through the AV node and Bundle of His, preventing chaotic conduction
What is the sequence of depolarization and contraction in the heart
SA node fires → atria depolarize and contract.
Signal reaches AV node (delayed).
Signal travels through AV bundle → bundle branches → Purkinje fibers.
Ventricles depolarize and contract.
what does the sequence of deporliraztion and contraction ensure in the heart
This ensures atrial contraction happens before ventricular contraction.
What is an ECG, and what does it measure
An ECG (electrocardiogram):
Records the electrical activity of the heart.
Detects the wave of depolarization and repolarization using surface electrodes.
What does the P wave represent on an ECG
The P wave represents atrial depolarization, which triggers atrial contraction
What does the T wave represent on an ECG
The T wave represents ventricular repolarization, which occurs as the ventricles relax
Why don’t we see atrial repolarization on an ECG
Atrial repolarization is hidden by the larger QRS complex, which represents ventricular depolarization
What is the significance of the PR interval on an ECG
The time taken for the electrical signal to travel from the SA node to the AV node.
It includes the delay at the AV node
(AV node to bundle of his)
What happens if the AV node fails to conduct signals properly
The ventricles may not contract properly.
This can lead to heart block or uncoordinated atrial and ventricular activity
what is cardiac output
the amount of blood pumped by either left or right ventricle per minute (L/min)
why does the left and right vent have to have the same cardiac output
to ensure the the systemic and pulmonary circuits are both equally manianted
what is the formula for cardiac output
HRxSV
list the cardiac output (VO2 max) for rested, untrainedmax , and althetes
rest: 5 L/min
untrained: 20 L/min
athletes: 30 L/min
what is the relationship between cardiac output and workrate (VO2)
cardiac output rises w workrate
compare the VO2 ax for untrained and trained
they will both have similar VO2 max but trained will have less heart rate and higher stroke volume
what is the relationship between O2 transport and cardiac output
-ficks equation: Vo2=HRxSVx(a-vo2)
-when cardiac output increases O2 will be transported to working muscles
-to increase o2 uptake, increase cardiac output and it will extract more O2 from arterial blood
why is workmate higher when excerise is performed with the arms than with the legs
-smaller muscle mass
-increased intra-thoracic pressure
-less effective muscle pump
-feedback to control centre
what does stroke volume equal
end-distalic volume(EDV) minus end-sytolic volume (ESV)
what is diastole
resting phase of the cardiac cycle between beats
what is systole
contraction phase of the cardiac cycle when ventricles pump out stroke volumes
what does EDV represent
maximum volume of blood the ventricle holds before contraction
what does ESV represents
minimum volume of blood left after the heart has ejected as much as it could during the contraction
Why the SV Calculation is (EDV - ESV):
-Blood Ejection: The heart doesn’t eject all the blood during systole
-SV measures only the usable portion of blood ejected with each beat.
what is the ratio for SV during excerise
Ejection fraction (EF) : percentage pf EDV ejected with each contraction
what happens to EF when excerise is increased
EF is increased
how to calculate EF
EF=SV/EDV
what is the reletionship between VO2 and SV during excerise
-SV increases then plates at 40% VO2 max
what is SV during rest vs excise
rest: 60-100ml
excersice: 70-120ml
what does SV being fitness dependant mean and explain how it is
it means fitness influnces SV
-increassed ventricle size to pump more blood
-greater blood volume (EDV)
what does increased blood flow cause
-increased blood pressure
-dilation of artielores; relaxation of smooth muscle
-constriction of arteilores in the gut area; sympathetic nervous system stimulation
what is Poiseulles law
quantifies how resistance (and thus blood flow) is affected by vessel characteristics
resistance to flow=(fluid viscosityxtube length)/radius of tube^4
why is the radius of the blood vessel significant in concern to poiseulles law
The radius of the blood vessels is the most significant factor influencing resistance because resistance is inversely proportional to the fourth power of the radius
what happens if you decrease tube radius by a factor of 2
increase flow by a factor of 16
what would happen to the resistance flow if there was a 33% decrease in radius of arterioles
would produce 400% increase in restisnce flow
what is the key takeaway of changing the radius of a blood vessel
a small change can have a signifanct change and impact on blood flow
what is blood composition made of
-red blood cells
-white blood cells
-platlets
-plasma (50-60% of blood, 90%water+10%solutes)
what is the percentage of blood of body mass
8%
what happens to blood volume in an athletes body
it increases
what are erythrocytes and its characteristics
-red blood cells
-binconcave discs 7 microns in diameter
-lifespan-120 days
-transports o2, co2,iron, In hemoglobin
what are hemoglobin levels for males and females
males-140-160
females-120-140
what is a hemocrit
ratio of volume of blood cells:total volume of blood
expressed as %
what is blood doping
-to increase RBc count to increase o2 in athletes
what are ways to blood dope
-donors, EPO injection, blood transfusion, altituide training
what is the risk for blood doping
polythermia vera: lead to blood clotting and increased viscosity
what is an arthymia
an irregular heartbeat
how to diagnose an arthymia
-heart rate
-amp. shapes of ECG
-time intervals
tachycardia
-type of arthymia
-HR is faster
- >100bpm at rest
bradychardia
-arthymia
-HR slower
- <60bpm at rest
what are the two types of fibrillation
-arthymias
-atrial- heart still functions as pump
-ventricle- heart does not function as effective pump
how to tell fib on ECG
-ECG is very disorganized
what is diffusion capability effected by
-partial pressure gradients
-thickness of rest membrane (length of path)
-#of red blood cells/hemoglobin
-surface area
how to increase diffusion
-surface area
-opening more capillaries in lungs
explain the Bhor effect
right shift: hemoglobin releases more O2 (less affinity) due to increased Co2, acidity and temp
left shift: hemoglobin holds onto more O2 (more affinity) due to decreasedCo2, acidity and temp
skeletal pump
-active muscles squeeze veins and push blood towards the heart
respiratory pump
-decrased press thoracic cavity during inspiration so that its easier for blood to return from lower portions of the body
via inferior vena cava-> thoracic cavity-> right atrium
what is cardiac muscle highly dependent
-aerobic metabolism
describe blood flow through the myocardium during rest and excerise
-blood flow stays roughly the same at 4% of total cardiac output the only diff is that 70-80% of that blood goes to active muscles during excerise so not a matter of how much just the location
describe hemoglobin
-carries o2 from lungs to tissue s
-each gram can carry 1.34 ml of o2 when fully saturated
what is the formula to find your max capacity of O2 carrying haemoglobin
grams x ml= 20.1ml
formula for SO2% saturation for hemoglobin
arterial blood sea level= 97% saturated
therefore
97.5 x 20.1ml =19.5ml
venous blood= 75 saturated
75 x 20.1= 15.1ml
O2 per 100ml of blood
describe the structure of the arteries and there functions
pressure recevoir, highly elastic, muscular
-diamtere 0.1-10 mm
-1.0 mm thickness
describe the structure of the arterioles and there functions
alter the diameter for resistance to blood flow, muscular wall, higher pressure
-diameter 10-100 um
-6.0 um in thickness
describe the structure of the capillaries and there functions
exchange of materials, thin wall+highly permeable, 100 000km long, 4-10um in diameter, 0.5 um in thickness
-endothelial layer, no muscle
describe the structure of the venule and there functions
-collects blood from capil.
-thin wall
-smooth muscle
-some fibrous tissue
-diamtere 10-100um
-1.0um in thickness
describe the structure of the veins and there functions
-thin wall smooth muscle and flaccid
-0.1-100mm-0.5mm
-easily collapse or expand to maintain venous return
