Lecture 1: Overview of the Cardiovascular System PDF

Lecture 1: Overview of the Cardiovascular System Learning Objectives Understand the role of the cardiovascular system in the human body Describe the major components of the cardiovascular system Differentiate between the systemic and pulmonary circulations Introduction The c...

Lecture 1: Overview of the Cardiovascular System Learning Objectives Understand the role of the cardiovascular system in the human body Describe the major components of the cardiovascular system Differentiate between the systemic and pulmonary circulations Introduction The cardiovascular system, also known as the circulatory system, is one of the most vital systems in the human body It plays a central role in transporting oxygen, nutrients, hormones, and waste products throughout the body  Components of the Cardiovascular System The Heart The muscular organ responsible for pumping blood Divided into four chambers: two atria and two ventricles Right side pumps blood to the lungs , left side pumps blood to the rest of the body Blood Vessels Arteries: Carry oxygenated blood away from the heart Veins: Carry deoxygenated blood back to the heart Capillaries: Tiny, thin-walled vessels where gas and nutrient exchange occurs Blood Composed of plasma and formed elements Transports oxygen, nutrients, hormones, and waste products This has been treated as a separate course Pulmonary vs. Systemic Circulation Pulmonary Circulation Blood flows from the right ventricle to the lungs Oxygen is loaded, and carbon dioxide is unloaded in the lungs Systemic Circulation Oxygenated blood is pumped from the left ventricle to the rest of the body Oxygen and nutrients are delivered to tissues, and waste products are collected  Anatomy of the Heart The heart is approximately the size of a clenched fist and is located in the thoracic cavity It is enclosed in a sac called the pericardium, which provides protection and lubrication Shape Apex: Blunt rounded point of cone Base: Flat part at opposite of end of cone Heart Chambers Atria Upper chambers of the heart Right atrium receives deoxygenated blood from the body Left atrium receives oxygenated blood from the lungs Ventricles Lower chambers of the heart Right ventricle pumps deoxygenated blood to the lungs Left ventricle pumps oxygenated blood to the body Heart Valves Valves ensure one-way blood flow within the heart Atrioventricular valves separate atria from ventricles Semilunar valves separate ventricles from major blood vessels Blood Flow Through Heart Cardiac Cycle The cardiac cycle represents one complete heartbeat It consists of systole and diastole phases Blood flows from high-pressure areas to low-pressure areas within the heart Functions of the heart Generating blood pressure Routing blood Heart separates pulmonary and systemic circulations Ensuring one-way blood flow Heart valves ensure one-way flow Regulating blood supply Changes in contraction rate and force match blood delivery to changing metabolic needs Heart Wall Three layers of tissue Epicardium: This serous membrane of smooth outer surface of heart Myocardium: Middle layer composed of cardiac muscle cell and responsibility for heart contracting Endocardium: Smooth inner surface of heart chambers