Chapter 25: Cardiovascular System PDF

Chapter 25: Structure and Function of the Cardiovascular System Two Parts of the Circulatory System Pulmonary circulation Moves blood through the lungs and creates a link with the gas exchange function of the respiratory system Systemic circulation Supplies all the other tissue...

Chapter 25: Structure and Function of the Cardiovascular System Two Parts of the Circulatory System Pulmonary circulation Moves blood through the lungs and creates a link with the gas exchange function of the respiratory system Systemic circulation Supplies all the other tissues of the body Types of Circulation Central circulation Blood that is in the heart and pulmonary circulation Peripheral circulation Blood that is outside the central circulation Laplace Law Describes the relation between wall tension, transmural pressure, and radius States that wall tension becomes greater as the radius increases Wall tension is also affected by wall thickness; it increases as the wall becomes thinner and decreases as the wall becomes thicker. Question #1 Blood flow is not based on which of the following properties? A. Pressure B. Vessel compliance C. Volume D. Contraction of the heart E. Distensibility of vessels F. All the above  Answer to Question #1 F. All the above Rationale: All the above are contributing factors to the flow of blood. Cardiac Cycle Used to describe the rhythmic pumping action of the heart Divided into two parts Systole: the period during which the ventricles are contracting Diastole: the period during which the ventricles are relaxed and filling with blood Cardiac Output Amount of blood the heart pumps each minute Determined by CO = SV x HR Stroke volume: the amount of blood pumped with each beat Heart rate: the number of times the heart beats each minute Venous return and contractility  Frank-Starling and Cardiac Reserve Frank-Starling Mechanism: the greater the volume of blood in the heart before contraction, the greater the volume of blood ejected from the heart Increased contractility from EDV stretch Cardiac reserve: maximum percentage of increase in cardiac output achieved above normal resting level