Topic 2.2 Structure and Function of the Cardiovascualr System

State the composition of blood Cellular: red blood cells (erythrocytes), white blood cell (leukocytes) and platelets (thrombocytes) Plasma: electrolytes, gases, nutrients, matabolic waste

Distinguish between the functions of erythrocytes, leukocytes and platelets

Describe the anatomy of the heart with references to the chambers, valves and major blood vessels of the organ Know it!

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Outline the relationship between pulmonary and systemic circulations Pulmonary circ- delivers deoxygenated blood to the lungs via pulmonary arteries to off-load CO 2. O 2 diffuses from the alveoli, passing into the pulmonary veins for return to the heart (lt. atrium) * Systemic circ. - delivers oxygenated blood to the bodies systems (aorta) and brings deoxygenated blood to the right side of the heart via vena cava.

Describe the relationship between heart rate, cardiac output and stroke volume at rest and during exercise Cardiac output = stroke volume x heart rate/1000 C.O. (aka. Q) = the amount of blood ejected from the left side of the heart in liters/min Stroke volume - amount of blood being ejected with each contraction (in milliliters/min) Heart rate = # beats per minute

Cont’d As you train, two primary things happen that increase your stroke volume and therefore allow you to have a decreased heart rate with the same cardiac output. One of the adaptations is that your heart simply becomes a stronger muscle. A stronger muscle can contract more forcefully and force out more blood with each contraction.

Cont’d Another adaptation is that the volume of your blood increases. As more blood is returned to the heart, the heart chambers actually stretch before they contract and push out all of the blood (Frank- Starling Law) This leads to an even stronger contraction that again increases stroke volume, and therefore increases cardiac output.

Analyze CO, SV and HR data for different populations at rest and during exercise Handout from page 43 of text