Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Management of acute coronary syndrome wikipedia , lookup
Coronary artery disease wikipedia , lookup
Jatene procedure wikipedia , lookup
Lutembacher's syndrome wikipedia , lookup
Myocardial infarction wikipedia , lookup
Cardiac surgery wikipedia , lookup
Quantium Medical Cardiac Output wikipedia , lookup
Antihypertensive drug wikipedia , lookup
Dextro-Transposition of the great arteries wikipedia , lookup
Grade 10 Applied Science - Biology Human Circulatory System The CIRCULATORY SYSTEM is the transport system of the body. It has FOUR functions: Transport of oxygen and carbon dioxide Distribution of nutrients and transport of wastes Maintenance of body temperature Circulation of hormones The system consists of THREE general components: FLUID in which materials are transported System of BLOOD VESSELS or spaces throughout the body in which the fluid moves A pump, the HEART, that pushes the fluid through the open spaces. The heart and blood vessels are commonly called the CARDIOVASCULAR SYSTEM The circulatory system is a complex network of tissues and organs throughout your body; yet, no cell is further than TWO cells away from a blood vessel. Thus, there are 96,000 km of blood vessels in your body to nourish your 100 trillion cells. The heart is no larger than your fist with of mass of about 300 grams; yet, the heart beats about 72 times/minute. Every minute, 5 L of blood cycles from your heart to the lungs, picks up oxygen and returns to the heart. Then, the heart pumps the oxygen-enriched blood and nutrients to the tissues of your body. Why is oxygen so important to your life? The circulatory system is two systems (see the attached diagram). PULMONARY CIRCUIT – The right side of the heart pumps blood to the lungs and returns oxygenatedblood to the left side of the heart SYSTEMIC CIRCUIT – The left side of the heart that pumps the oxygenate blood to all parts of the body and carries deoxygenated blood back to the heart. HEART STRUCTURE The left and right sides of the heart are separated by a wall of muscle called the SEPTUM Each side (or pump) consists of a thin-walled ATRIUM and a thick-walled VENTRICLE. The atria receives blood for the veins and pumps it into the ventricles. When the heart muscles contract, a valve of the heart prevents blood from flowing backwards. HEART PHYTHMS, SOUNDS and PRESSURE The heart has two specialized bundles of nerves that control its beating. SINOATRIAL (SA) NODE – acts as a pacemaker ATRIOVENTRICULAR (AV) NODE – passes the nerve impulses to the ventricles to cause them to contract in unison. The heart sound is the closing of the valves. When the atria are relaxed (called DIASTOLE), they fill with blood. As the atria push blood into the ventricles, the ventricles contract to force blood into the arteries. This contraction is SYSTOLE. The increase in pressure forces the AV valves to close…creates the LUBB sound. As the ventricles relax, the pressure inside decreases closing the semilunar valves and preventing a backward flow of blood. This closing is the DUBB sound. BLOOD PRESSURE is the pressure exerted on the walls of the arteries when the ventricles of the heart contract. Blood pressure is measured in mm Hg. Blood pressure is measured with a SPHYGMOMANOMETER. A stethoscope is used to listen to the sound of blood entering the artery as air is slowly released from the sphygmomanometer. The pressure on the gauge of the sphygmomanometer when the sound is first heard is the SYSTOLIC BLOOD PRESSURE. As the cuff of the sphygmomanometer is deflated, the sound disappears. This is the DIASTOLIC BLOOD PRESSURE. If your blood pressure is too high, it put stress on the walls of the arteries which may result in a stroke or heart attack. High blood pressure is called HYPERTENSION. Low blood pressure is HYPOTENSION can lead to dizziness, blurred vision or loss of consciousness. BLOOD VESSELS ARTERIES carry blood away from the heart The AORTA is the largest artery of the body and closest to the heart From the arteries, blood flows into smaller blood vessels called ARTERIOLES, and then, smaller vessels called CAPILLARIES. As the capillaries merge, they become larger vessels called VENULES which merge into VEINS. The veins have valves that only open in one direction to allow blood to flow only to the heart. Contractions of the muscles surrounding the veins also help blood to flow to the heart BLOOD COMPONENTS (Use Page 89 in the textbook to complete this table) Component Description Function Plasma Red Blood Cells White Blood Cells Platelets Do Questions 1-5 on Page 93 in the textbook