1. Chapter 19
The Blood
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2. Introduction Circulatory system (cardiovascular)
Consists of the heart, blood vessels and blood
Functions of circulatory system
Transport- O2, CO2, nutrients, wastes, hormones, and stem cells
Protection- destroy microorganisms and cancer cells, neutralize toxins, and initiates clotting to prevent blood loss; also vehicle for the spread of infection, inflammation, and pathogens
Regulation - fluid balance, stabilizes pH of ECF, produces ion balance (Ca+, K+, Na+) and temperature control, absorbs and neutralizes acids (ie: lactic acid)
The Blood
Comprised of plasma, formed elements, plasma proteins
Plasma – (47%-63% of blood volume) 92% water; 5xs MORE PROTEIN in plasma than interstitial fluid
serum – identical to plasma except for the absence of fibrinogen
Formed elements approximately 45% of blood volume. Erythrocytes (RBC), leukocytes (WBC). platelets
Plasma proteins account for 7% of plasma; 90% formed in the liver
FIBRINOGEN (4%)
Other elements- electrolytes, nutrients, blood gases, etc.
Hematology – the study of blood

3. Components and Properties of Blood
7 kinds of formed elements
erythrocytes - red blood cells (RBCs)
Ratio: 1000 RBCs to every 1 WBC
platelets
cell fragments from special cell in bone marrow
leukocytes - white blood cells (WBCs)
5 leukocyte types divided into 2 categories:
granulocytes (with granules- contain enzymes)
neutrophils, eosinophils, basophils
agranulocytes (without granules)
lymphocytes, monocytes

5. Separating Plasma From Formed Elements
HEMATOCRIT - % of blood volume comprised of RED BLOOD CELLS (RBC)
Erythrocytes 37% to 52%
Males: – androgens stimulate higher RBC production
Females: 37-47
white blood cells and platelets
buffy coat- 1% total volume
plasma
47% - 63% of total volume
complex mixture of water, proteins, nutrients (fatty acids, amino acids, glucose, iron, cholesterol, vitamins), electrolytes, nitrogenous wastes (urea), hormones, and gases
CENTRIFUGE separates plasma from formed elements

6. Erythrocytes 4.8 – 5.4 million RBC / cu mm of blood*
Biconcave; No nucleus, mitochondria or other organelles- no protein synthesis, ATP by anaerobic respiration
Loss of organelles increases surface area allowing for higher gas exchange and cytoskeletal flexibility enabling cells to stack on top of one another to squeeze through small capillaries walls
Protein – hemoglobin- Transports gases: most O2 (98.5%); some CO2 (23%)
280 million/per each RBC [WOW!]
Anemia defined as insufficient RBCs or hemoglobin
Plasma membrane has ABO and Rh antigens/markers- for blood typing
* fluid oz = 1cu/mm

7. Blood Antigens Antigens – cell markers/receptor
complex protein molecules ON SURFACE OF CELL MEMBRANE unique to individual. Used to provoke an immune response
distinguishes self from foreign
RBC antigens called agglutinogens - basis for blood typing
Two types of agglutinogens -antigen A &B
type A person has A antigens ∎ type B person has B antigens
type AB has both A and B antigens - rarest - type AB
type O person has neither antigen - most common - type O
Antibodies (agglutinins - produce agglutination); Anti-A; Anti-B
appear 2-8 mos. after birth; reach maximum concentration at age 10
antibody-A and/or antibody-B (both or none) PRESENT IN THE BLOOD PLASMA NOT ON THE CELLS
**Antibodies recognize and bind to specific antigens  cause clumping of cells  AGGLUTINATION
do not form antibodies against your own antigens
Blood transfusion require compatibility between PLASMA antibody proteins and RBC- erythrocytes
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8. Blood type A has antibody B (anti-B) in its plasma
“Antigen”
Blood type A has antibody B (anti-B) in its plasma
Blood type B has antibody A (anti-A) in its plasma
Blood type AB has NO antibodies in its plasma
Blood type O has both antibody A (anti-A) and antibody B (anti-B) in its plasma

9. ABO Blood Typing Antibodies attack and agglutinate foreign antigens
Anti A
Anti B
Antibodies called agglutinins found IN PLASMA are anti-A and anti-B
What blood type is anti-A going to agglutinate?(A) What blood type is anti-B going to agglutinate? (B)
AB blood type has neither A or B antibodies or it would continually clot itself. If you add antibodies to AB blood it will clot.
O Blood type has both antibodies and can only receive O type blood.
Type A
Type B
Type AB
Type O

10. Rh (Rhesus) Blood Group System
Two types: Rh+ and Rh-
Rh antigen (ANTIGEN D) “present” on RBC of Rh+ blood type
(+) sign is an indication that antigen marker is “PRESENT” on RBC
Rh antigen is “ABSENT” on Rh- blood type
(-) is indication that antigen marker is NOT present on RBC
Anti-D antibody will be produced if a person with Rh- blood is exposed Rh+ blood via transfusion or in the birthing process
RESULT: the person starts making Rh antibody (anti-D).
Ex: First pregnancy Rh- mother is carrying Rh+ fetus  if mixing of blood occurs at birth, mother's body starts making Rh antibodies
Anti-D is ONLY present in Rh negative blood
universal donor Type O negative (–)
lacks Red Blood Cell antigens so recipient’s antibodies will not agglutinate
universal recipient Type AB – rarest blood type
lacks plasma antibodies; no anti- A or B; can receive A, B, AB, O

11. Leukocytes- White Blood Cells
Less than 1% of the formed elements
5,000 – 10,000 WBC / cu mm of blood
Conspicuous nucleus
DO NOT HAVE HEMOGLOBIN
Plasma membrane has histocompatibility antigens
used to match cells, tissues and organs during donation procedures
Protect the body from infections
A Differential Blood Count determines the % of the 5 times of WBC types
Migrate in and out of the blood
Mostly found in connective tissues and lymphoid organs

12. Types of Leukocytes
Granulocytes- Specific granules that contain enzymes or chemicals for DEFENSE against pathogens and stain conspicuously distinguishing each cell from others
neutrophils (60-70%)
barely-visible granules in cytoplasm; 3 to 5 lobed nucleus
eosinophils (2- 4%)
large rosy-orange granules; bilobed nucleus
basophils (<1%)
large, abundant, violet granules (obscure a large S-shaped nucleus)
Agranulocytes - Non-specific granules (lysosomes containing enzymes in the cytoplasm) are inconspicuous to the light microscope and have relatively clear looking cytoplasm.
lymphocytes (25-33%) [B and T]
variable amounts of bluish cytoplasm (scanty to abundant); ovoid/round, uniform dark violet nucleus
monocytes (3-8%)
largest WBC; ovoid, kidney or horseshoe shaped nucleus

13. Formed Elements of Blood

14. Granulocyte Functions
neutrophils - increased numbers in BACTERIAL INFECTIONS
eosinophils - increased numbers in PARASITIC INFECTIONS, collagen diseases, ALLERGIES, diseases of spleen and CNS
basophils - stimulate ALLERGIC REACTIONS; increased numbers in chicken pox, sinusitis, diabetes
secrete histamine (vasodilator) – widens blood vessels
secrete heparin (anticoagulant –blood thinner) – promotes the mobility of other WBCs in the area by preventing blood clotting
Stimulates release of neutrophils and eosinophils – for infections
Become modified Mast Cells present in connective tissue
lymphocytes - increased numbers in diverse infections and immune responses
Two types “T” and “B”(antibodies)
destroy cells (cancer, foreign, and virally infected cells)
monocytes - increased numbers in viral infections and inflammation [no antibody for viral infection]
transform into macrophages inside tissues
“present” antigens to activate other immune cells - antigen presenting cells (APCs)

15. Disorders
Leukocytosis (“cyto”=cell “sis”= process): increases ABOVE 10,000/cu mm
Leukopenia (“penia”=deficiency): decreases BELOW 5,000/cu mm of blood
Leukemia (“emia”= blood condition): CANCER OF LEUKOCYTES
Reduces competency of immune system to infection
myeloid leukemia – uncontrolled granulocyte (N,E,B) monocyte, lymphoid leukemia - uncontrolled lymphocytes, crowd normal cells
acute leukemia – appears suddenly, progresses rapidly, death within months unless treated.
chronic leukemia –undetected for months, slow progression, survival time three years
Opportunistic infections – pathogenic organisms develop that would not usually mount an infection in a healthy immunocompetent individual
Decrease RBC = anemia; Decrease platelets= hemorrhage

16. Normal and Leukemic Blood

17. Platelets
Thrombocytes- platelets - small cytoplasmic fragments of megakaryocytes
normal platelet count - 250,000 – 400,000 platelets/L
secrete vasoconstrictors; stick together to form platelet plugs to seal small breaks; secrete clotting factors
attract neutrophils and monocytes; phagocytize and destroy bacteria
Circulate for 5-9 days in the blood stream
Thrombocytosis: when # of platelets goes UP  excessive clots
Thrombocytopenia: when # of platelets goes DOWN  excessive internal bleeding
megakaryoblast duplicates its DNA repeatedly without dividing forming a megakaryocyte
megakaryocyte sprouts long tendrils that protrude into the endothelium of blood capillaries
moving flow of blood breaks off the tendrils into platelets that travel through the blood