Chapter 19 Key Terms - Anatomy and Physiology 2e

Introduction

Chapter 19 focuses on the key terms related to the cardiovascular system, specifically the heart. It explores the anatomy, functionality, and various physiological processes associated with the heart.

Key Terms

Anatomy of the Heart

• Anterior cardiac veins: Vessels that drain the anterior surface of the right ventricle directly into the right atrium.
• Anterior interventricular artery (LAD): Major branch of the left coronary artery.
• Aortic valve: Located at the base of the aorta.
• Atrioventricular (AV) node: Cluster of cells in the right atrium regulating the impulses received from the SA node.
• Atrioventricular valves: One-way valves between the atria and ventricles, including the tricuspid and mitral valves.
• Atrium: Upper chambers of the heart receiving blood; includes the right and left atrium.
• Chordae tendineae: Connective tissues extending from the AV valves to papillary muscles.
• Coronary arteries: Supply blood to the heart, with branches such as the left and right coronary arteries.

Heart Functionality

• Cardiac cycle: Period from atrial contraction to ventricular relaxation.
• Cardiac output (CO): Volume of blood the ventricles pump per minute.
• Heart rate (HR): Number of heartbeats per minute.
• Stroke volume (SV): Blood pumped by ventricle per contraction.
• Ejection fraction: Percentage of blood pumped out of ventricles with each contraction.

Electrical Activity

• Electrocardiogram (ECG/EKG): Records the heart's electrical activity.
• P wave: Depolarization of the atria.
• QRS complex: Represents ventricular depolarization.
• T wave: Ventricular repolarization.

Heart Development and Structures

• Bulbus cordis: Part of the primitive heart tube developing into the right ventricle.
• Primitive heart tube: Forms from endocardial tubes, developing into structures like the ventricles and atria.
• Septum: Divides the heart into chambers, including the interventricular and interatrial septum.

Additional Terms

• Autorhythmicity: Heart muscle's ability to initiate impulses independently.
• Baroreceptor reflex: Autonomic reflex regulating heart function based on blood flow.
• Frank-Starling mechanism: Relationship between heart muscle stretch and contraction force.
• Systole and Diastole: Phases of heart contraction and relaxation.

Summary

This chapter provides an in-depth understanding of the heart's anatomy, its functions, and its physiological mechanisms. The key terms help describe how the heart maintains circulation and supports overall cardiovascular health. Understanding these terms is crucial for comprehending the complex processes that drive heart functionality and health.