THE CIRCULATORY SYSTEM
The Function of the Circulatory System The main role is to transport nutrients, carbon dioxide, oxygen, hormones, and wastes through the body.
Main Organs of the Circulatory System: Heart Blood Vessels
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
Pulmonary circuit The blood pathway between the right side of the heart, to the lungs, and back to the left side of the heart. Systemic circuit The pathway between the left and right sides of the heart.
THE HEART The heart causes blood to flow throughout the body because of it’s pumping action; The human heart has 4 chambers; The top 2 are called the atria; they receive blood The bottom 2 are called ventricles and they pump the blood out of the heart
Interior & Exterior of Heart
BLOOD Made of liquid and solids parts Bright-red when full of oxygen and dark-red when it is oxygen poor Very important because blood is what carries nutrients, wastes, and gasses throughout the entire body
PARTS OF BLOOD: The liquid part of the blood is known as plasma. It is 97% water. It enables the solid particles to flow through the vessels.
The solid parts are white blood cells, red blood cells, and platelets. Red blood cells (Erythrocytes)- Red Blood Cells Carry hemoglobin and oxygen. Do not have a nucleus and live only about 120 days. Can not repair themselves. carry oxygen molecules
White blood cells-Leukocytes fight disease Fight infection and are formed in the bone marrow Five types – neutrophils, lymphocytes, eosinophils, basophils, and monocytes.
Platelets-Thrombocytes make blood clots so you don’t bleed to death These are cell fragment that are formed in the bone marrow from magakaryocytes. Clot Blood by sticking together – via protein fibers called fibrin.
Blood traveling through vessels
BLOOD VESSELS 3 types of vessels: Arteries, Veins, and Capillaries Arteries take blood away from the heart and are thick and muscular Veins take blood back to the heart and are thin Capillaries are microscopic and hook to the individual cells
ARTERIES
VEINS
Capillaries
Disorders of the Circulatory System Anemia - lack of iron in the blood, low RBC count Leukemia - white blood cells proliferate wildly, causing anemia Hemophilia - bleeder’s disease, due to lack of fibrinogen in thrombocytes Heart Murmur - abnormal heart beat, caused by valve problems Heart attack - blood vessels around the heart become blocked with plaque, also called myocardial infarction
REAL HUMAN HEART