Potentially useful information: one mL = one cm3 = 10-6 m3, one mmHg = 133.3 Pa (N/m2). SV = EDV â ESV. CO = HR X SV. Ejection Fraction = SV/EDV
Hints: calculate heart rate for each condition. Remember to calculate work for the entire volume of blood that is pressurized i.e., end diastolic volume (EDV). Therefore you will need to use the data provided to calculate the EDV to answer this question.
The work done by the heart is Pressure-Volume work. While both ventricles are doing work, in this problem you will just calculate the work done by the left (high pressure) ventricle. If both pressure and volume are expressed in SI units, their product is N·m (work!) In this assignment you will calculate the work done by the left ventricle of the heart each minute to support a cardiac output of 5L/min.
B) Individuals with hypertension (high blood pressure) have a much greater resistance in their blood vessels and thus their heart not only has to produce greater pressure, it will have a much greater volume left following contractions (end systolic volume, ESV) Calculate the work the heart (for the identical cardiac output of 5L/min) in an individual with stage one hypertension for which these values apply: systolic blood pressure of 150 mmHg, an ejection fraction of 40% and a stroke volume of 60mL.
C) In this individual, how much greater is their cardiac work (@ blood pressure 150 mmHg) than a normal individual with normal blood pressure (120 mmHg)?
Please answer these questions COMPLETELY and I'll be sure to leave a "thumbs up"! Thank you!
Potentially useful information: one mL = one cm3 = 10-6 m3, one mmHg = 133.3 Pa (N/m2). SV = EDV â ESV. CO = HR X SV. Ejection Fraction = SV/EDV
Hints: calculate heart rate for each condition. Remember to calculate work for the entire volume of blood that is pressurized i.e., end diastolic volume (EDV). Therefore you will need to use the data provided to calculate the EDV to answer this question.
The work done by the heart is Pressure-Volume work. While both ventricles are doing work, in this problem you will just calculate the work done by the left (high pressure) ventricle. If both pressure and volume are expressed in SI units, their product is N·m (work!) In this assignment you will calculate the work done by the left ventricle of the heart each minute to support a cardiac output of 5L/min.
B) Individuals with hypertension (high blood pressure) have a much greater resistance in their blood vessels and thus their heart not only has to produce greater pressure, it will have a much greater volume left following contractions (end systolic volume, ESV) Calculate the work the heart (for the identical cardiac output of 5L/min) in an individual with stage one hypertension for which these values apply: systolic blood pressure of 150 mmHg, an ejection fraction of 40% and a stroke volume of 60mL.
C) In this individual, how much greater is their cardiac work (@ blood pressure 150 mmHg) than a normal individual with normal blood pressure (120 mmHg)?
Please answer these questions COMPLETELY and I'll be sure to leave a "thumbs up"! Thank you!
Related textbook solutions
Related questions
Question 1
- A moderate increase in extracellular potassium will
Increase heart rate due to a more negative EK | ||
Decrease heart rate due to a more negative EK | ||
Increase heart rate due to a less negative EK | ||
Decrease heart rate due to a less negative EK |
Question 2
- Apply Atropin will directly
Decrease parasympathetic innervation and increase heart rate | ||
Increase parasympathetic innervation and decrease heart rate | ||
Decrease sympathetic innervation and increase heart rate | ||
Increase sympathetic innervation and decrease heart rate |
Frog ECG is recorded using
An electrical stimulator | ||
Three wires including the one that is connected to the hook | ||
A force transducer | ||
Three wires and a force transducer |
Question 4
- How would you differentiate atrial contractions fromventricular contractions?
A. | Observe the heart beating and tap the table to label it | |
B. | From the size of the contractions | |
C. | Correlate it with the electrical trace, if the electrical traceis typical. | |
D. | Both A and C |
Question 5
- In this week's experiment, _________signal(s) will be recordedto study the frog cardiac functions.
mechanical (contractile) | ||
electrical (ECG) | ||
both mechanical and electrical | ||
blood flow |
Question 6
- In this week's experiment, the heart is hooked at the________
either atrium or ventricle | ||
ventricle | ||
atrium |
sympathetic/increase | ||
parasympathetic/decrease | ||
Sympathetic/decrease | ||
parasympathetic/increase |
Question 8
- The frog heart can be slowed or stopped by over stimulation ofthe vagus nerve. When apply ACh to the heart, if the frog heartstop beating, you should
Wash the heart with warm Ringers | ||
Apply a few drops of Isuprel | ||
Massage the heart | ||
All of the above | ||
Observe the trace and do nothing |
Question 9
- The pacemaker in the frog heart is the __________ and thepacemaker in the mammalian heart is the ________
AV, SA node | ||
SV, SA node | ||
SA, SV node | ||
SA, SA node |
Question 10
- Which of the following statements is TRUE regarding the frogheart
There is no autorhythmic cells found in the frog ventricle. | ||
Oxygenated and deoxygenated blood are mixed completely insidethe frog ventricle | ||
There are two atria and two ventricles. | ||
Deoxygenated blood flows to the frog lungs and skin. |
