Introduction to the Human Cardiovascular System PDF

Introduction to the Human Cardiovascular System  INTRODUCTION The cardiovascular system is Figure 1-2(f) transport system of body It comprises blood, heart and blood vessels. The system supplies nutrients to and remove waste products from various tissue of body. The...

Introduction to the Human Cardiovascular System  INTRODUCTION The cardiovascular system is Figure 1-2(f) transport system of body It comprises blood, heart and blood vessels. The system supplies nutrients to and remove waste products from various tissue of body. The conveying media is liquid in form of blood which flows in close tubular system.  FUNCTION OF CARDIOVASCULAR SYSTEM Transport nutrients, hormones Remove waste products Gaseous exchange Immunity Blood vessels transport blood, Carries oxygen and carbon dioxide. Also carries nutrients and wastes Heart pumps blood through blood vessels COMPONENTS OF CARDIOVASCULAR SYSTEM BLOOD HEART BLOOD VESSELS  BLOOD The Blood: Blood cells & Plasma 1- Erythrocytes - Red Blood Cells 2- Leucocytes 3- Thrombocytes Plasma is fluid portion  HEART Heart is a four chambered, hollow muscular organ approximately the size of your fist Location: – Superior surface of diaphragm – Left of the midline – Anterior to the vertebral column, posterior to the sternum Chapter metsyS ralucsavoidraC ,18 6  HEART Figure 18.1 Chapter 18, Cardiovascular System 7  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  BLOOD VESSELS Blood Vessels -A closed network of tubes These includes: Arteries Capillaries Veins  BLOOD VESSELS -Arteries(Distributing channel) Thick walled tubes Elastic Fibers Circular Smooth Muscle –Capillaries: microscopic vessels One cell thick –Veins:draining channel  BLOOD VESSELS General structure 1-Tunica intima 2-.Tunica media 3-.Tunica adventitia  ARTERIES Blood vessels that carry blood away from the heart are called arteries. They are the thickest blood vessels and they carry blood high in oxygen known as oxygenated blood (oxygen rich blood).  ARTERIES Accompanied by vein and nerves Lumen is small No valves Repeated branching  CLASSIFICATION OF ARTEIES Elastic- e.g. (Aorta & its Major branches) Muscular -e.g.(Renal, Testicular, Radial, Tibial etc). Arterioles< 0.1 mm Terminal arterioles  CAPILLARIES (5-8 micron) The smallest blood vessels are capillaries and they connect the arteries and veins. This is where the exchange of nutrients and gases occurs. BODY CONTAINS TWO KINDS OF CAPILLARIES CONTINUOUS-SKIN, LUNG, SMMOTH MUSCLE, CONNECTIVE TISSUES FENESTRATED- PANCREAS,ENDOCRINE GLANDS, SMALL INTESTINE,CHOROID PLEXUS,CILLIARY PROCESS etc.  SINUSOIDS SINUSOIDS- Large irregular vascular space (30- 40 micron) eg.Liver, Spleen, Bone marrow, suprarenal, Parathyroid etc.  VEINS Blood vessels that carry blood back to the heart are called veins. They have one-way valves which prevent blood from flowing backwards. They carry blood that is high in carbon dioxide  VEINS Thin Walled Large irregular lumen Have valves Types: Large Medium Small  VEINS Factors responsible for venous return: 1.Muscle contraction 2.Negative intrathoracic pressure 3.Pulsation of arteries 4. Gravity 5. Valves  ANASTOMOSIS Communication between vessels End arteries are vessels whose terminal branches do not anastomose with branches of arteries supplying adjacent areas. Collaterals are accompanying extra arteries to an area.  ANASTOMOSIS ARTERIOVENOUS ANASTOMOSIS: 1. Skin of nose 2. Lips 3. External Ear 4. Mucus membrane of GI &nose 5. Erectile tissue of sex organ 6. Thyroid 7. Tongue  END ARTERIES END ARTERIES: 1-Central artery of retina 2- Arteries of spleen, liver, kidneys, metaphyses of bones long 3- Central branches of cerebral cortex  CIRCULATION –Coronary circulation – the circulation of blood within the heart. –Pulmonary circulation – the flowof blood between the heart and lungs. –Systemic circulation: blood between the heart and the cells of the body. –Fetal Circulation  SYSTEMIC AND PULMONARY CIRCULATION Pulmonary circulation The flow of blood between the heart and lungs. Systemic circulation The flow of blood between the heart and the cells of the body. Figure2918.5 Chapter 18, Cardiovascular System CORONARY CIRCULATION: ARTERIAL SUPPLY Chapter 18, Cardiovascular System 30 Figure 18.7a  PORTAL CIRCULATION Portal circulation - the flow of blood between two set of capillaries before draining in systemic veins.