BLOOD & CIRCULATORY SYSTEM. Prepared by Mr.Yeung

Size: px

Start display at page:

Download "BLOOD & CIRCULATORY SYSTEM. Prepared by Mr.Yeung"

Opal Carpenter
6 years ago
Views:

1 BLOOD & CIRCULATORY SYSTEM Prepared by Mr.Yeung

2 CIRCULATORY SYSTEM Overview Every cell in a living organism must have direct access to its nutrient supply Single celled organisms rely on simple diffusion to move materials into the cell Multi-cellular organisms require some type of system

3 CIRCULATORY SYSTEM Functions Carries nutrients and wastes to and from cells Carries chemical messages between different cells Distributes heat throughout the body Maintains fluid levels in the body Defends against invading organisms

4 CIRCULATORY SYSTEM KEY PARTS 1. Blood 55% Plasma 45% Formed Elements Cells 2. Vessels Arteries, veins and capillaries 3. Heart white blood cells 4. Periphery Organs red blood cells Kidneys Platelets Liver (<1%) cell fragments Intestines Humans have ~5L of blood Lungs

5 Blood composition BLOOD

6 BLOOD - PLASMA Fluid portion of the blood Contains 90% water Other 10% dissolved substances Contains dissolved materials gases, glucose, amino acids, ions and vitamins. wastes and hormones.

7 BLOOD PLASMA CONT D Soluble proteins Immunoglobulins antibodies and carrier/transport proteins Fibrinogens aid in blood clotting

8 RED BLOOD CELLS STRUCTURE You are a water thief The way you steal water is to have the water absorb into your clothing. You must climb and squeeze through tiny windows What shape would you be to maximize the amount of water?

9 BLOOD ERYTHROCYTES RED BLOOD CELLS Red blood cells (RBCs) 4-6 million per mm 3 (ml) of whole blood Function to transport gas around the body

10 BLOOD - ERYTHROCYTES Structure biconcave disks, increased surface area, Increases ability to exchange gas Have no nucleus at maturity Increased space for hemoglobin, increases ability to carry oxygen proteins in cell membranes determine blood type

11 BLOOD ERYTHROCYTES CONT D Continuously produced in bone marrow Mainly in large bones the skull, ribs, vertebrae, and ends of the long bones. Production of red blood cells is stimulated by erythropoietin From kidney In response to decreased oxygen in blood

12 BLOOD ERYTHROCYTES CONT D Contain hemoglobin Red iron containing pigment Heme portion of molecule forms an unstable, reversible bond with oxygen. Carries 20 ml oxygen per 100 ml of blood Oxygenated state = oxyhemoglobin Bright red Reduced state = deoxyhemoglobin purple-blue.

13 BLOOD ERYTHROCYTES CONT D Structure of Hemoglobin

14 BLOOD ERYTHROCYTES CONT D Lifespan- 120 days Destroyed in liver by fixed macrophages Hemoglobin is broken down Iron is recycled-taken to bone marrow Heme portion is degraded and excreted as bile pigments

15 BLOOD ERYTHROCYTES CONT D Possible disorders Anemia- decreased red blood cells Most common type comes from iron deficiency Carbon monoxide poisoning Carbon monoxide binds at heme sites more strongly than oxygen

17 BLOOD LEUKOCYTES WHITE BLOOD CELLS White blood cells (WBCs) General term for a variety of cells without hemoglobin Less numerous than RBC s per mm 3 of whole blood Larger cells, nucleated

18 BLOOD LEUKOCYTES CONT D Important part of the immune system. able to enter fluids surrounding tissues to fight infection Blood stream is only a means of transport to location of infection.

19 BLOOD LEUKOCYTES CONT D Fighting Infections: Fight infection by destroying pathogens Other leukocytes will also clean up the mess! Pus is composed of dead invaders and leukocyte fragments

20 MACROPHAGE ENGULFING BACTERIA Fig

21 BLOOD LEUKOCYTES CONT D Lifespan Different types live different lengths of time Some live only a few days-die combating invading pathogens Some live months or years

22 BLOOD LEUKOCYTES CONT D Change in numbers may indicate disease Infectious mononucleosis Due to Epstein-Barr virus AIDS HIV Human Immunodeficiency Virus Decreased number of T lymphocytes Leukemia Blood cancer Uncontrolled numbers of WBC s

23 BLOOD - THROMBOCYTES Platelets fragmentation of large cells called megakaryocytes 150, ,000 per mm 3 of whole blood Tiny cells that play important role in blood clotting.

24 BLOOD THROMBOCYTES CONT D Blood clotting Platelets form a plug for immediate stoppage of bleeding

25 BLOOD CLOTTING Steps: Platelets contain the starter enzyme for blood clotting to occur. Platelets releases thromboplastin and converts prothrombin to thrombin. Thrombin joins with fibrinogen to form fibrin. Fibrin traps red blood cells and clots. Thromboplastin à Prothrombin à Thrombin + Fibrinogen èfibrin

CH 11 Blood OUTLINE: Functions of Blood Composition of Blood Blood Cell Disorders Blood Types Blood Clotting Functions of Blood Transportation

1 CH 11 Blood OUTLINE: Functions of Blood Composition of Blood Blood Cell Disorders Blood Types Functions of Blood Transportation Protection Regulation ph Temperature Composition of Blood Plasma: liquid