KIN 105 Lecture Notes - Lecture 2: Exercise Intensity, Vasodilation, Extracellular Fluid

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indigobee70

23 Jan 2018

School

University of Waterloo

Department

Kinesiology

Course

KIN 105

Professor

Christopher Vigna

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Document Summary

Lecture 2 cardiac and vascular structure and diagram. 2 pumps left side of the heart goes to the systemic circulation. Right side of the heart goes to the pulmonary circulation. Venous return volume of blood returning to the heart. Myocardium muscular tissues of the heart, made up of many cardiomyocytes. The heart conveys energy to blood in the form of pressure. Pressure gradient moves systemic circulation to and from the heart. Cardiac cycle the repeating pattern of contraction and relaxation. One full cardiac cycle lasts approximately 0. 8 seconds at rest (75 bpm) One full cardiac cycle lasts approximately 0. 33 seconds at heavy exercise (180 bpm: filling time limitation during heavy exercise. *note: usually referring to the ventricular events unless specified when talking about systole and diastole. Atria and ventricle contract out of phase to enhance filling of the ventricles before ventricular contraction. 2 pumps, 2 distinct vascular networks each network has arterial (higher pressure) and venous (low pressure) circulation.

Related Questions

1. The fish heart is a modified tube with _____________chambers arrayed one after the other.

2. The ____________ cycle consists of systole and diastole.

3. The spontaneous depolarization of cells in the ________________ passes through the left and right atria as a wave to finally cause the contraction of the heart.

4. ____________ is fluid formed from blood plasma minus the larger proteins.

5. A weakened section of an artery is known as a(n) ___________

6. The ________ is the amount of blood pumped by the heart each minute.

7._________ are subcellular packets of clotting enzymes.

8.________________ are basically packets of hemoglobin.

9. A normal value for blood pressure should be about

Answer: ______________________.

10. Veins contain _______________that assist in the movement of blood back to the heart.

11. The ______________delays the contraction of the ventricles to allow them to fill with blood.

12. During the cardiac cycle, contraction is called _____________and relaxation is called ___________.

13. The ________________ is the tough sac of connective tissue around the heart.

14. ___________________results when the blood's ability to carry oxygen is decreased.

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Question 1. Increased peripheral edema could be caused by:

a. blocked lymph vessels

b. decreased capillary blood pressure

c. increased concentration of albumin in the blood

d. slowed heart rate

Question 2. The pulse pressure of a healthy student is most likely to be:

a. 5 mm Hg

b. 30 mm Hg

c. 95 mm Hg

d. 120 mm Hg

Question 3. beta-blockers inhibit the activity of beta-adrenergic receptors and change the function of the heart by:

a. increasing heart rate and increasing contractility

b. increasing heart rate and decreasing contractility

c. decreasing heart rate and increasing contractility

d. decreasing heart rate and decreasing contractility

Question 4. In cardiac pacemaker cells, the L-type calcium channels:

a. open during diastole

b. close when the membrane potential rises above threshold

c. are located in the cell membrane

d. pump Ca2+ ions into the sarcoplasmic reticulum

Question 5. Dr. Campbell used an elliptical trainer for 40 minutes at the gym. Although the workload remained constant, Dr. Campbellâs heart-rate rose to 150 beats per minute during the first 5 minutes, stayed at that level for the next 25 minutes and then started to rise. It was 180 beats per minute at the end of the exercise period.

What was the time interval between QRS complexes when Dr. Campbellâs heart rate was 180 beats per minute?

a. 3.3 ms

b. 33 ms

c. 333 ms

d. 3333 ms

Question 6. In the question 5 above, Dr. Campbellâs heart rate is most likely to have risen during the last 10 minutes of exercise because his:

a. lungs were becoming congested

b. atrial cells were fatigued

c. extracellular Ca2+ concentration had increased

d. hematocrit increased due to sweating

Question 7. A Physiology student is sitting still in a cold igloo. After 30 minutes, she stands up, walks slowly around the igloo, and suddenly starts to shiver.

The student preserved their core temperature while they were sitting by:

a. depressing their Frank-Starling mechanism

b. decreasing the extracellular Ca2+ concentration

c. relaxing smooth muscles in their peripheral circulation

d. increasing the resistance of arterioles in their arms and legs

Question 8. In the question 7 above, the student started to shiver soon after walking because:

a. their atria started to fibrillate

b. their ventricles started to fibrillate

c. blood moved to the periphery, became cold, and chilled the core when it returned to the chest

d. the ATP concentration in their skeletal muscles had dropped to zero

Please use the following scenario for answering the questions 9 and 10.

A newly discovered drug binds to myosin molecules in cardiac muscle (and nowhere else) and increases the probability that myosin molecules in ventricular cells will bind to actin filaments when the intracellular Ca2+ concentration rises. The drug is being tested as a potential therapy for patients with heart failure.

Question 9. This drug might help people who have low cardiac output by:

a. increasing peripheral resistance

b. increasing the force developed by ventricular cells

c. increasing the isovolumic contraction time

d. increasing heart rate

Question 10. The increased binding of cardiac myosin molecules to actin might prevent the drug from being a useful treatment by:

a. slowing ventricular relaxation

b. decreasing the duration of systole

c. decreasing resistance of capillaries

d. slowing heart rate

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