Lab report ch 28 PDF

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Lectures will provide an overview of functional anatomy at all levels, from the systems to the tissues. The goal is to provide a mechanistic understanding of the different structures in our body as a foundation for human-health oriented studies....

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BIOS255 WEEK 1 Lab: #6 Effect of Exercise on Cardiac Output LABORATORY REPORT Activity 6: Effect of Exercise on Cardiac Output Name: Shamir Tyson Instructor: Professor Smith Date: September 8, 2013

PREDICTIONS 1. During exercise: HR will increase 2: During exercise: SV will increase 3. During exercise: CO will increase

MATERIALS AND METHODS 1. Dependent Variable: EDV, ESV, and Cardiac Cycle Length 2. Independent Variable: Level of physical activity (resting or exercise) 3. Controlled Variables: Health, gender, age, weight and height 4. What instrument was used to measure cardiac volumes? An MRI was used to measure Cardiac Volumes 5. Does the instrument that was used to measure cardiac volume use X-rays? Explain. This device is similar to an X- Ray however the MRI obtains 2- dimensional images then processed them to obtain 3d images.

RESULTS See Table 2: Resting and Exercising Cardiac Cycle Length, EDV, and ESV See Graph: Resting and Exercising HR, EDV, and ESV

1. Resting and exercising cardiac cycle length: a. What was the average resting cardiac cycle length? 815+846+829=2,490/3= 830

b. What was the average exercising cardiac cycle length? 389+364+414= 1167/3= 389 c. The range of normal resting cardiac cycle length is between 818 and 858 ms. did average cardiac cycle length increase, decrease, or not change with exercise? The cardiac cycle decreased with exercise 2. Resting and exercising EDV: a. What was the average resting EDV? 141+139+142=422/3= 140.67 b. What was the average exercising EDV? 139+135+140= 414/3= 138 c. The range of normal resting EDV is between 135 and 145 ml for these subjects. Did average EDV increase, decrease, or not change with exercise? The EDV stayed in the same range regardless of exercise or not.

3. Resting and exercising ESV: a. What was the average resting ESV? 73+70+68=211/3= 70.33 b. What was the average exercising ESV? 39+32+35=106/3=35.33 c. The range of normal resting ESV is between 65 and 75 for these subjects. Did average ESV increase, decrease, or not change with exercise? The ESV decreased with exercise

See Table 3: Resting and Exercising HR, SV, and CO See Graph: Resting and Exercising SV and CO

4. Resting and exercising HR: a. What was the average resting HR? 72.29 b. What was the average exercising HR? 154.24

c. The range of normal resting HR is between 70 and 73 beats per minute for these subjects. Did average HR increase, decrease, or not change with exercise? The heart rate increased with exercise

5. Resting and exercising SV: a. What was the average resting SV? 70.34 b. What was the average exercising SV? 102.67 c. The range of normal resting SV is between 60 and 80 ml for these subjects. Did average SV increase, decrease, or not change with exercise? The average SV increased with exercise 6. Resting and exercising CO: a. What was the average resting CO? 5,084.88 b. What was the average exercising CO? 15,835.82 c. The range of normal resting CO is between 4.2 L per minute and 5.84 L for these subjects. Did average CO increase, decrease, or not change with exercise? The cardiac output increased with exercise.

DISCUSSION 1. What caused the change in HR with exercise? The heart rate increased with exercise being that more blood is being pumped when the heart contracts 2. Discuss the effect of venous return and heart rate on exercise EDV. An increase in venous return of blood to the heart will result in greater filling of the ventricles during diastole. This will increase the amount of blood in the ventricles and the EDV 3. What caused the change in ESV volume with exercise? The amount of blood remaining in the ventricle after contraction changed after exercise therefore decreasing the ESV

4. Why did SV change with exercise? After exercising more blood is being ejected from the left and right ventricle causing a change in the Stroke Volume

5. Discuss the importance of the change in CO with exercise? With exercise there is an increase in the volume of blood being pumped by the heart each minute, which in return increases the cardiac output as well

6. Restate your predictions that were correct, and give data from your experiment that support them. Restate your predictions that were not correct and correct them, giving supporting data from your experiment that supports your corrections. My predictions that the HR will increase were correct. Heart rate increases with exercise as more blood is being pumped through the heart with each contraction. My prediction that the SV will increase was correct as the stroke Volume increases during exercise being that more blood is being ejected through the ventricles. And lastly my prediction that the CO would increase was also correct being that the volume of blood being pumped by the heart increased with exercise.

APPLICATION 1. We measured the stroke volume of the left ventricle. What was the average stroke volume of the right ventricle at rest and after exercise? The resting stroke volume is 70.34 and after exercising was 102.67

2. Assume that for one beat, the stroke volume of the left ventricle is greater than that of the right ventricle. Explain why in a normal heart this would be corrected on the next beat The amount of blood would be corrected with the next beat being that the volume of blood within each ventricle should remain almost equal to maintain normal function.

3. Explain why elite athletes have a lower than normal heart rate, yet have a higher than normal ability to increase cardiac output. Athletes heart rate tend to be lower then the normal heart rate because they tend to pump a higher volume of blood with each contraction (cardiac output). This is due to conditioning of the heart from exercising and physical activity. Being that the body is getting the needed amount of blood, the heart doesn’t need to contract as much as a normal person.

DISCUSSION

1. What caused the change in HR with exercise? The cause for the increased heart rate was related to need for more oxygenated blood to supply the need of the muscles for activity. The increased muscle activity caused an increase in CO2 and other waste products that need to be removed and new brought in to replenish in order to strive for homeostasis.

2. Discuss the effect of venous return and heart rate on exercise EDV.

During exercise, the rhythmic pump of your muscles facilitates venous return by forcing blood through the one-way valves that lead to the heart. What's more, increased lung activity creates a change in thoracic pressure that draws blood toward your heart. Regular exercise improves venous return by increasing total blood volume, increasing end diastolic volume, and increasing the size and contractile strength of the heart muscle. Exercise also increases the number of capillaries at the muscle where oxygen and CO2 are exchanged, reducing peripheral resistance

3. What caused the change in ESV volume with exercise? A higher volume of blood being supplied out to the body and utilized at the peripheral capillary level.

4. Why did SV change with exercise? Increased related to the raised pressure of the stressed heart to supply blood to the body.

5. Discuss the...

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