Blood is 55% Plasma (Liquid)

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4 Blood is 55% Plasma (Liquid) The plasma portion of blood is: 91% Water Maintains blood volume Transports molecules 7% Proteins (ie: clotting proteins, albumin, immunoglobulins ) 2 % Salts, gases (O 2, CO 2 ), nutrients, wastes, hormones, vitamins, etc

5 Blood is 45% Formed Elements (Solids) The solid portion of blood is: Red Blood Cells (RBCs) Erythrocytes White Blood Cells (WBCs) Leukocytes Platelets Thrombocytes

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7 Blood p. 249 of text

8 Structure of Red Blood Cells

9 No nuclei Red Blood Cells (RBC s) Transport CO 2 and O 2 and H + (acts like a buffer) Biconcave discs Live for ~ 120 days (4 months) Contain hemoglobin molecules, carbonic anhydrase, and antigens Made in the red bone marrow Erythrocytes

10 Do NOT copy FYI for later Transports oxygen as oxyhemoglobin (bright red) Hb + O HbO 2 Hb attaches to oxygen when it s cool, high ph, and low pressure (ie: at the lungs)! Transports carbon dioxide as carboxyhemoglobin Hb + CO HbCO 2 Transports hydrogen ions as reduced hemoglobin (thus acting as a buffer) Hb + H HHb Note: fetal hemoglobin has a greater affinity for oxygen than maternal hemoglobin!

11 White Blood Cells (Leukocytes) Role: Fight Infection - by producing antibodies OR through phagocytosis of pathogen Formed in bone marrow & lymph tissue WBC s can squeeze out of blood vessels to attack invaders.

12 White blood cell squeezes out of blood vessel to attack invaders

13 WBCs Differ from RBCs: have nucleus Larger & fewer in number

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15 1. Basophiles release histamine when damaged which causes capillaries to dilate and release fluid fluid leaks into tissues = swelling 2. Neutrophils 3. Eosinophils 4. Monocytes 5 Types of WBCs Phagocytic becomes macrophages (really large) at site of infection (inflammatory response) 5. Lymphocytes = T-cells triggers immune response = B-cells release antibodies

16 Platelets (Thrombocytes) They are just fragments of cells (irregular shape) with no nuclei We produce ~ 200 billion/day Made in bone marrow Platelets

17 Aid in blood clotting Recognize micro tears in blood vessels & bind together to form a blood clot

18 Clot formation: After injury, an enzyme is secreted to change a blood protein called fibrinogen (soluble) to fibrin (insoluble protein) platelets + fibrinogen fibrin (in plasma) Fibrin clumps at injury site & partially blocks leak Fibrin threads trap blood cells to clot the injured site

19 BLOOD TYPES

20 Antigens/Antibodies & Blood Type Antigens and Antibodies have different but related functions!

21 Antigen: an identification glycoprotein on a RBC 2 kinds of antigens on human RBC's: A and B Therefore, 4 possible blood types: Antigen A Type A blood Antigen B Type B blood Antigens A & B Type AB blood No Antigens Type O blood

22 Antibody: a protein designed to combat any foreign protein Made by the WBC cells in the body Will bind to foreign proteins with foreign antigens This causes AGGLUTINATION = clumping WBC s will then destroy the agglutinated cells Antigen (Foreign) + Antibody (Yours) Y + = (Agglutinization) Y Y Y Y Y

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25 Our blood has antibodies that are opposite to the antigens we have on our RBC s. WHY? So we don t attack our own blood!

26 This is what it looks like Type A has B antibodies Type B has A antibodies Type O has A and B antibodies Type AB has No antibodies

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28 Therefore blood transfusions are tricky: introducing foreign antigens can lead to DEATH Note: Antibodies are REMOVED from donated blood they cannot cause agglutination Blood Type A B AB O A B AB O yes clumps yes clumps Blood donor clumps yes yes clumps clumps clumps yes clumps yes yes yes yes

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30 Do NOT copy The Rh factor is another antigen that may be present on the RBC. The presence of this antigen plays a role in childbirth. If you are Rh+ you have the antigen and don t have the D antibodies. (85% of Caucasions are Rh+) Rh + NO ANTIBODIES If you are Rh you don t have the antigen. You don t normally have the D antibodies, but can make them if you are exposed to Rh antigens. Rh - HAS ANTIBODIES, BUT ONLY WHEN EXPOSED TO Rh + BLOOD

31 Do NOT copy If Rh antigens are mixed with Rh antibodies, agglutination occurs.

32 Do NOT copy Donor Recipient Anti-Rh Antibodies in Recipient's Blood Rh + Rh - Will Produce anti-rh Antibodies Rh - Rh + Will Not Produce anti-rh Antibodies

33 Rh - Blood Rh + Blood

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35 WHY ELSE IS THIS IMPORTANT? If an Rh- mother can has an Rh+ baby, complications can occur with a second pregnancy. Normally, the mother / fetal blood does not mix or cross the placenta. However, at birth, there is usually some mixing, and the mother will begin to produce Rh antibodies in response to the Rh antigens on the baby's Rh+ RBC's. There is no danger for either the mother or the first baby.

36 Do NOT copy BUT If the mother becomes pregnant with another Rh+ baby, the mother s antibodies (made during the birth of the 1 st child) are small, and can cross the placenta. These antibodies will agglutinate the baby's blood. This will cause the baby to die / be still born (Erythroblastosis).

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38 How can this be prevented? Do NOT copy When the first Rh+ baby is born, doctors can destroy the Rh+ blood cells in the mother's plasma before the mother has time to make the Rh antibodies. An injection of Rh immune globulin injection (RhoGAM) does this.

39 THE END of blood & blood types