At
The Oxygen-hemoglobin dissociation curve:
1. draw it
2. what does it govern?
3. When it shifts to the right is oxygen easier or harder to bind?
4. What are factors that cause a shift to the right?
5. When it shifts to the right what is this effect called?
6. What is this effect's impact?
2. it governs o2 binding to hemoglobin at alveoli and o2 release at tissues
3. oxygen is harder to bind as it shifts to the right
4. increased H+, increased co2 concentration, increased blood temperature
5. Bohr effect - harder to bind o2 because of co2 displacement but easier to release
6. enhances release of o2 at tissues while enabling oxygenation of blood in the lungs
I'm out of room for questions...
What is the most important circulatory control mechanism for rapidly controlling systemic blood pressure?
Explain the barorecptor reflex, including the receptors, reflec pathway, and what specific changes that this mechanism would bring about to change blood pressure.
Tissues are able to regulate their own blood flow based on their active needs. When local o2 levels drop, local arterioles vasodilate to decrease resistance and up blood flow. More blood arrives carrying more oxygen, once the demand it met the body goes back into balance.
barorecptors are located in the carotid and aortic arch. They detect stretch of the vessel wall, which is an indication of blood pressure. The sympathetic system causes vasoconstriction or dilation to allow for easier blood flow.
What is surfactant? What does it help control? If there was not enough surfactant what could happen?
What is alveolar pressure?
What is the value when..
the glottis is open
inspiration
expiration
What is transpulmonary pressure?
Alveolar pressure - the air pressure inside the alveoli
0 mm/Hg
-1 mm/Hg
1 mm/Hg
Transpulmonary pressure is the difference between alveolar pressure and pleural pressure. Ap- Pp = Tp
What is the respiratory zone? What is the conducting zone?
Respiratory zone - terminal bronchioles, alveolar ducts, alveolar sacs -- where gas exchange occurs, mostly in alveoli
Conducting zone - trachea, bronchi, nose -- not involved with gas exchange
What is the primary source of the cardiac vector?
Draw the expected cardiac vector during ventricular contraction within a triangle representing the cardiac leads. Identify each lead including the orientation. Demonstrate how the component of lead 1 can be obtained graphically from this vector.
B- top right (+, -)
C- bottom (-,-)
A-B (I), B-C (III), A-C (II) (MCV)
I = B-A, II = C-A, III = C-B
to find component, right angles on the lead in question down to the mcv.
The amount of gas dissolved in a liquid is proportional to the partial pressure of that gas above the liquid. It is equal to the concentration in alveolar air.
Draw the pressure/volume curve for the left ventricle at rest with an
R-R of 500 ms
systolic arterial pressure is 150 mmHg
diastolic arterial pressure is 75 mmHg
diastolic ventricular pressure is 5 mmHg
List and label the 4 steps of the cardiac cycle and identify them on the plot
What would change if this curve if it were for the right ventricle
what are the stroke volume and ejection fraction for your diagram
redraw it as if you were running a marathon
systolic line on top, diastolic line on bottom
on bottom diastolic curve, the dvp would be where things start. From 5 mmHg follow th ediastolic line on the bottom up to a good spot (if given an edv to the edv)
then go straight up until systolic is reached
then follow curved systolic line left making sure to reach peak sap
then once dap is reach straight line back down to dvp.
1. goes along bottom horizontal: rest and refill
2. goes up: isovolumetric contraction
3. going horsizontally on top: ejection
4. goes down: isovolumetric relaxation
SV = edv - esv (make them up if not given, make them easy)
ejection fraction: sv/edv
if this were the right ventricle the pressures would be much lower
if you were running a marathon increase those pressures and increase that edv --> more blood flow
What is the main way that oxygen is transported around the body/
What about co2?
What does the _____ buffer system do?
Bound to hemoglobin
Mainly as a bicarbonate ion in plasma
The bicarbonate buffer system serves to enable blood to resist large changes in pH
What is the vetilation-perfusion ratio? Draw the associated graph.
The ventilation perfusion ratio is a concept to describe the degree to which the alveoli that are well-ventilated are also well - perfused, enabling optimal gas exchange.
It's the y axis with Pco2 (mmHG) and x axis Po2 (mmHg) with a negative exponential. at both extremes va/q = 0, inf no gas exchange occurs, in the middle it is normal, Pcos (40), Po2 (104)
What is dead space?
Unrelated but there's so much content...
What is alveolar ventilation? How do you calculate the rate of alveolar ventilation?
Dead space is air in the conducting passageways so like air in your nose
AV - rate at which air is delivered to/from the alveoli
Rate of AV - total volume of air entering gas exchange areas of the lungs per minute
Va = freq*(Vt - Vd)
Draw the heart diagram. Include all chambers and the blood pathway from body to body again including valve names.
body--> svc and ivc --> right atrium --> tricuspid valve --> right ventricle --> pulmonary valve --> pulmonary artery --> lungs --> pulmonary vein -->left atrium --> bicuspid valve --> left ventricle --> aoritc valve --> aorta --> body
Carbon dioxide dissociation curve:
1. draw it
2. describe it
3. What effect shifts the curve down when the oxygen saturation is high?
4. where in the body does this effect predominate?
how the total amount of blood co2 depends on carbon dioxide partial pressure
the haldane effect - high o2 concentration displaces the co2 in the blood
the haldane effect effect predominates at the lungs as new oxygen comes in and replaces the co2 so the co2 can release and be expired from the body and the oxygen can be transported ot the tissue.
Draw and label the cardiac action potential curve. Include labels of ion movement in each segment.
What does the action potential curve look like with a more rapid heart beat?
If you have a mutation that decreases the calcium channel conductance, what happens to the cardiac action potential and why?
If you have a mutation that increases the potassium channel conductance, what happens to the cardiac action potential and why?
Starting at -90 mv then going up is the I_Na which is the sodium current responsible for the depolarization (action potential inititation)
Then I_Ca is the calcium current responsible for phase 2, the plateau. triggers contraction, inactivates slowly
Then I_k the potassium current is responsible for pahse 3 the action potential repolarization, slow to activate, slow to deactivate, and exhibits rectification
It would cause a shorter plateau and a lower cap voltage. If there is less calcium current the I_k current takes over faster and repolarization happens sooner.
It would cause a shorter plateau, faster repolarization, and lower cap. If there is more I_k the membrane returns to resting potential more quickly.
What are the differences between heavy breathing and normal quiet breathing?
1. Muscles
2. neural groups
3. draw the neural activation pattern for quiet breathing
4. how would that drawing change if we wanted to increase the rate of breathing?
1. Diaphram vs abdominal muscles & intercostal muscles - internal for expiration and external for inspiration
2. dorsal respiratory group, ventral respiratory group
3. ramp up for inspiration, flat for expiration
4. the ramp would get steeper and the firing rate would be closer together, expiration time would be shorter
What is ectopic foci, which kind is it?
Abnormalities of impulse conduction - reentry excitation, wavelength < path length
Abnormalities of impulse formation - automaticity, ectopic foci (when the beat starts not in the SA node), abnormal beats.
What is pulmonary circulation? There are two circulations in the pulmonary system. Name them and describe their function.
Pulmonary circulation is the system to transport de-oxygenated blood from the heart to the lungs to be re-oxygenated before being sent back out to the body
The two circulations
pulmonary vessels - supply venous blood from whole body to the alveolar capillaries to add oxygen and remove carbon dioxide. Low pressure - high flow
1. pulmonary artery - from heart to lungs
2. pulmonary vein - from lungs to heart
Bronchial vessels - supplies blood to the lung tissues, originates from systemic circulation. High pressure - low flow
What is the most important factor controlling respiration?
What receptors in your body can detect this factor?
There are two types of this receptor involved in detection for respiration name them both and describe what each one specializes in detecting.
chemoreceptors (central chemoreceptor specifically)
Peripheral chemoreceptors - found in aortic and carotid bodies, strongly stimulated by decreased arterial o2 concentrations, sends signals to drg to increase breathing when low
Central chemorecpetive area - area in the medulla that is highly sensitive to changes in blood pco2 or H+ concentrations -- direct stimulus is done by H+ ions only but they cannot cross the blood-brain barrier alone so co2 crosses the barrier, then reacts with water to form carbonic acid, which is then further decomposed into H+ and bicarbonate, where H+ then can directly stimulate the receptive area.
Describe pleural space, pleural pressure, and pleural fluid. Why is it important that the pleural pressure maintains its designated polarity? What could happen if it does not? Give an example of a condition that would cause a change in polarity - give cause and symptoms.
Pleural space - the potential space between the lungs' pleura lining and the thoracic's pleura lining
Pleural fluid - slippery fluid that allows lungs to slide against the membrane
Pleural Pressure - negative pressure to suction the lungs to the walls of the thoracic cavity
Because the negative polarity ensures that the lungs are being suctioned to the lining of the thoracic cavity. Without that the body will not be able to efficiently bring in air.
A pleural effusion is a collection of liquid in the pleural space and this can bring the polarity closer to positive causing a collapse or difficulty/pain while breathing because the lungs won't be able to expand as much.
Pneumothorax is when air is in the pleural space and it can also bring the polarity closer to positive. Also causing difficulty breathing and a possible lung collapse because they won't be as suctioned to the thoracic cavity.
Draw an ECG for a patient with a heart rate of 110 bpm, label all axes wiht values, important segments of the waveform, identify the heart action that each major segment of the waveform represents.
Draw one for a patient in afib
Draw one in the case where the ecg electrodes were placed on your left shoulder (+) and your right lower rib (-).
Time between R peaks should be .55 seconds.
p - arterial depolarization
QRS complex - ventricular depolarization
t - ventricular repolarization
Afib should have no p wave
the wrong placement should have the qrs complex essentially flipped - it's too close to the heart and doesn't aligh with the mean cardiac vector so the magnitude wouldn't be as strong.
What is the Hering - Breuer inflation reflex?
stops inspiration due to lung over-stretching, also results in increases in the rate of respiration
Draw the aortic pressure curve, the ventricular pressure curve, and the ventricular volume curve over two cycles with a HR of 80 bpm at rest. Label your axes and include values. They can be on the same or different plots.
I'm not going to bother describing it, we're just going to correct the drawing, but the opening/closing of the valves should be mitral closes, aortic opens, aortic closes, mitral opens
Name and describe the four steps in respiration.
Pulmonary ventilation - breathing, inflow and outflow of air between the atmosphere and lungs
External respiration - Diffusion of oxygen and carbon dioxide between the alveoli and the blood
Respiratory Gas Transport - transport of gases in the bloodstream
Internal respiration - transport of oxygen and carbon dioxide in the blood stream and from the body's tissue
This is going to suck again. I'm so sorry.
Draw the lung volume over time curve. Label each pulmonary capacity as it corresponds to a section of the graph, give a description, and an estimate of the lung capacity at this point.
Inspiratory capacity - maximum amount of air a person can breathe in if starting at normal expiratory level (~3200 mL) (IC = VT + IRV)
Functional Residual Capacity - the amount of aire that remainsin the lungs after a normal expiration (~2300 mL) (FRC = ERV + RV)
Vital Capacity - maximum amount of air a person cna voluntarily move into and out of lungs (~4600 mL) (VC = IRV + VT + ERV)
Total Lung Capacity - maximum volume to which the lungs can be expanded (~5800 mL) (TLC = IRV + VT + ERV + RV)
This is going to suck again. I'm so sorry.
Draw the lung volume over time curve. Label each pulmonary volume as it corresponds to a section of the graph, give a description, and an estimate of the lung capacity at this point.
Tidal volume - volume of air inspired or expired with normal breathing (~500 mL)
Inspiratory respiratory volume - extra volume of air that can be inspired with max force (~3000 mL)
Expiratory respiratory volume - extra volume of air that can be expired with max force (~1100 mL)
Residual volume - volume of air remaining in the lungs after maximum forced expiration (~1200)