1. THE CIRCULATORY SYSTEM Objectives: 1.Explain the functions of the circulatory system 2.State the main components of the circulatory system. 3.Describe the structure and function of blood 4.Know what types of blood are compatible with each other and why.

2. Three Main Components of the Circulatory System 1. Fluid in which materials are transported (i.e. blood) 2. Vessels to provide controlled paths (i.e. veins, arteries, capillaries) 3. A pumping device to move the fluid around (i.e. heart)

3. BLOOD: IT’S ALIVE! - An average adult has 5L of blood

4. Function of Blood 1.Transports oxygen and nutrients to cells 2. Transports carbon dioxide and wastes away from cells 3. Helps maintain homeostasis: –Transports chemical messages throughout the body (ex. hormones), –helps maintain acceptable fluid levels, –helps maintain a constant temperature 4. Is part of the immune system, used to transport immune cells throughout the body

5. Components of Blood

7. Blood cells are produced from stem cells in your bone marrow

8. 1) Erythrocytes (RBC’s) Made in the bone marrow Destroyed in liver and spleen Contain gas-binding haemoglobin and iron; carry O2( combines with Fe) and CO2 No nucleus or mitochondria Blood types: different glycoproteins on cell surface

9. FOUR blood types: A, B, AB and O Surface ANTIGENS or markers consisting of glycoproteins (proteins with attached polysaccharides), are found on the plasma membranes of red blood cells There are two types of surface antigens, A or B The presence or absence of antigens A and B on the plasma membrane of the rbc of a person, determines that person’s blood type

10. The body’s own blood type antigen(s) is recognized by the immune system as “self”, but other blood type antigens will be considered “non-self” by the body’s immune system Within the blood plasma there will be ANTIBODIES to the opposite blood type These antibodies have a complementary shape to the antigen and will bind to it. –eg. A person with antigen A on their red blood cells will have antibody B (Anti-B) in the plasma –A person with antigen B on their red blood cells will have –antibody A (Anti–A) in the plasma

11. BLOOD TYPEANTIGEN ON RBC’sANTIBODY IN PLASMA A B AB O A B BA NONE AB

12. When incompatible blood types combine, agglutination or clumping of red blood cells will occur. The antibodies present in the recipient’s plasma will attack and bind to the donated red blood cells’ antigens clumping the red cells together and preventing them from circulating. This creates blockages in small capillaries For a donation to be successful, the recipient’s plasma must NOT have an antibody that causes the donor’s cells to agglutinate.

13. Blood Types

14. Blood TypeCan Receive A B AB O  (NOTE: the antibodies in the plasma of the donor are not considered since they are very diluted during the transfusion and do not cause clumping.) A and O B and O A, B, AB and O O

15. Another surface antigen important in blood typing is the Rh factor or Rhesus factor Rh+ means the antigen is present on red blood cells (85% of people) Rh – means the antigen is absent on red blood cells (15% of people) e.g. type B+ means type B blood with the Rh factor present

16. Rh+ has Rh antigen Therefore Rh+ has no Rh antibodies. Rh- has no Rh antigen Therefore Rh – has Rh antibodies. THEREFORE… –Rh+ can donate to Rh+ only –If Rh+ donated to Rh- the Rh antibodies in Rh- blood would attack the antigens in the Rh+ blood being donated. –Rh- can donate to Rh- and Rh+ because Rh- has no antigen to be attacked and Rh+ has no antibodies to do the attacking.

17. Blood TypeCan Receive A- A+ B- B+ AB- AB+ O- O+ A- and O- A+ A- O+ and O- B- and O- B+ B- O+ and O- A- B- and O- Universal recipient O- O+ and O-

18. 2) Leukocytes (white blood cells) Made in the bone marrow and lymph nodes Have a nucleus Different types Function: As part of the immune system, they can produce antibodies to attack pathogens or they can be phagocytic and engulf pathogens.

21. 3) Platelets Repair wounds by releasing clotting factors (proteins) to help cells stick together No nucleus Produced in bone marrow

22. Your Task Read and complete the worksheet on ‘Blood and its Components’ H/W complete worksheet on Blood Typing

23. Plenary 1.What is the function of blood? 2.Name the two major components of blood. 3.What is the function of hemoglobin? 4.What is the function of red/white blood cells? 5.What is an antigen/antibody? 6.What is the difference between Rh-positive and Rh-negative blood? 7.A person with A- blood is given blood from a donor with O+ blood. What happens and why?