BIO 188 Study Guide #15
1. Trace blood flow in order through the major vessels and circuits. For each vessel
or heart chamber, indicate whether the level of oxygenation is relatively high or
aortic valve HIGH O2
2. What are the phases of the cardiac cycle and what happens during each? Describe
the muscular, valve, fluid, and electrical activity associated with each.
Diastole and Systole. Diastole is when ventricles relax and atria contract, blood
flows from atria to ventricles, mitral and tricuspid valves open, aortic and
pulmonic valves closed. Systole is when ventricles contract and the atria relax,
blood then flows out of heart into pulmonary artery and aorta, mitral and tricuspid
valves close, aortic and pulmonic valves open.
3. Given EDV, ESV, and HR, how do you calculate SV, CO, and EF? What are
normal resting values for SV, CO, and EF? On average, how often does an RBC
pass through the heart?
CO = SV x HR. SV=EDV-ESV. EF=SV/EDV. Normal SV=70mL/beat. CO
resting is 5.04L/min. EF resting is 0.6. Every minute.
4. Starting with the outermost, name the three types of “—cardium” and the function
Pericardium – protects heart, Myocardium – muscle responsible for pumping
blood, Endocardium – lining of heart chamber that minimizes heart turbulance
5. What is the cause of the twisting or torque motion of the heart as it contracts?
Because the right side of the heart is bigger than the left
6. During one minute, approximately how much time is spent in diastole and how
much is spent in systole?
Twice as much time in diastole as in systole
7. Compare and contrast atrial and ventricular contraction in terms of strength,
length, timing, valve activity, and maximum blood pressure.
Atria contract for longer than ventricle. Mitral and tricuspid valves are open
longer than the aortic and pulmonic valves. Ventricle contraction stronger than
atria. The more the ventricle is contracted, the higher the blood pressure
8. How would a massive drop in blood volume affect CO? Why would tachycardia
be expected as a result?
CO would drop dramatically causing heart rate to increase to make up for it for
the lower volume as to keep CO the same
9. What factors affect SV?
preload, strength of contraction (decreases ESV) and afterload.
10. What factors can influence HR? What hormones, if any, regulate these factors?
Automatic nervous system (blood pressure, blood composition). Epinephrine.
11. What is the sequence of events in the conducting system (nervous tissue) of the
heart through one cardiac cycle? Correlate these events with the signals on an