Ch 19 Learning Objectives

Cardiovascular System: The Heart

19.1.1 Describe the general function of the cardiovascular system.

to circulate blood throughout body to meet changing needs of body cells

• delivery of oxygen & nutrients

• removal of CO2 & other waste products

19.1.2 Differentiate among the three primary types of blood vessels.

arteries: transport blood away from the heart

veins: transport blood toward the heart

capillaries: exchange gases

19.1.3 Describe the general structure and function of the heart.

central componenet of cardiovas. system

• hollow, four chambered organ that pumps blood throughout body

• 2 sides of heart;

  • right side receives deoxygenated blood & pumps to lungs

  • left side receives oxygenated blood from lungs & pumps it to body

  • atrium receives blood from veins

  • ventricle pumps blood to artery

• great vessels: blood entering & leaving

  • large arteries & veins that directly connect with specific chambers of the heart

• 2 sets of valves: keeps blood moving in correct direction

  • atrioventricular valves

  • semilunar valves

activity depends on rhythmic electrical stimulation controlled by ans

19.1.4 Compare and contrast pulmonary circulation and systemic circulation of the cardiovascular system. Trace blood flow through both circulations.

pulmonary: movement of blood to & from lungs for gas exchange

• blood moves from right side of heart to lungs & then back to left side of heart

• vessels are short, have wider lumens, have pressure

systemic: movement of blood to & from systemic cells

• blood moves from left side of heart to body tissues & returns it to right side of heart

• operates at higher pressure

pattern of blood flow: right side of heart, lungs, left side of heart, systemic cells, right side

19.2.5 Describe the location and position of the heart in the thoracic cavity.

within thoracic cavity in mediastinum (central space between lungs)

its orientation is tilted, the heart is rotated slightly to the right side

• where the right side is more forward, left side is more to the pack

upper broad part is the base, lower pointed end is the apex, projects downward & slightly forward toward the left

19.2.6 List and describe the structural components of the pericardium.

fibrous pericardium: tough, outer layer that protects the heart, holds it in place, & prevents it from overexpanding

serous pericardium: thin, inner layer with 2 parts:

• parietal layer: lines inside of fibrous pericardium

• visceral layer: covers surface of heart

inbetween has serous fluid to reduce friction for serous pericardium

19.2.7 Describe the function of the pericardium and the purpose of the serous fluid within the pericardial cavity.

pericardium: protects & holds the heart

serous fluid: reduces friction while heart beats

19.3.8 Compare the superficial features of the anterior and posterior aspects of the heart.

anterior: right ventricle & atrium are most prominent

• most noticeable is right auricle

• anterior view shows more of the right side

posterior: shows more of the left

sulci: grooves between chambers of heart

19.3.9 Name the three layers of the heart wall and the tissue components of each.

epicardium: outermost heart layer (serous layer of visceral pericardium)

• simple squamous ET & underlying layer of areolar CT

myocardium: middle layer of heart wall

• cardiac muscle tissue & thickest layer

• contraction of cardiac muscle gives force to pump blood

• myocardium may change in thickness as we age or if we do rigorous exercise

endocardium: internal surface ofheart

• simple squamous ET & underlying layer of areolar CT

19.3.10 Characterize the four chambers of the heart and their functions.

right atrium: receives deoxygenated blood from body through superior & inferior vena cava

right ventricle: pumps deoxygenated blood to lungs through pulmonary trunk/arteries

left atrium: receives oxygenated blood from lungs through pulmonary veins

left ventricle: pumps oxygenated blood to entire body through aorta, has the thickest wall because it pumps blood at the highest pressure

atriums are separated by interatial septum

ventricles are separated by interventricular septum

19.3.11 Compare and contrast the structure and function of the two types of heart valves.

19.3.12 Describe the location and function of the fibrous skeleton.

19.3.13 Identify the coronary arteries, and describe the specific areas of the heart supplied by their major branches.

19.3.14 Explain the significance of coronary arteries as functional end arteries.

19.3.15 Describe blood flow through the coronary arteries.

19.3.16 Identify the coronary veins, and describe the specific areas of the heart drained by their major branches.

19.4.17 Describe the general structure of cardiac muscle, including intercalated discs.

19.4.18 Explain how cardiac muscle meets its energy needs.

19.5.19 Identify and locate the components of the heart’s conduction system.

19.5.20 Compare and contrast parasympathetic and sympathetic innervation of the heart.

19.6.21 Describe an SA nodal cell at rest.

19.6.22 Define autorhythmicity and explain its relationship to the pacemaker potential of the SA node.

19.6.23 Describe the steps for SA nodal cells to spontaneously depolarize and serve as the pacemaker cells.

19.6.24 Describe the spread of the action potential through the heart’s conduction system.

19.6.25 Describe the conditions at the sarcolemma of cardiac muscle cells at rest.

19.7.26 List the electrical events of an action potential that occur at the sarcolemma.

19.7.27 Briefly summarize the mechanical events of cardiac muscle contraction.

19.7.28 Define the refractory period.

19.7.29 Explain the significance of the plateau phase.

19.7.30 Identify the components of an ECG recording.

19.8.31 Identify the two processes within the heart that occur due to pressure changes associated with the cardiac cycle.

19.8.32 List the five phases of the cardiac cycle.

19.8.33 List and describe what occurs during the five phases of the cardiac cycle.

19.8.34 Explain the significance of ventricular balance.

19.9.35 Define cardiac output.

19.9.36 Explain what is meant by cardiac reserve.

19.9.37 Define chronotropic agents, and describe how they affect heart rate.

19.9.38 Explain how autonomic reflexes alter heart rate.

19.9.39 List the three variables that may influence stroke volume.

19.9.40 Define each of the three variables, and describe the factors that influence each variable and how each variable affects stroke volume.

19.9.41 Summarize the variables that influence cardiac output.

19.10.42 Explain how postnatal heart structures develop from the primitive heart tube.

19.10.43 Describe septal defects that may occur during development.