BloodChapter 14

Online Tutorials on RBC, WBC

• http://www.wisc-online.com/objects/ViewObject.aspx?ID=AP14604

• http://www.wisc-online.com/objects/ViewObject.aspx?ID=ap14704

What is blood?

• The only fluid tissue

• Transport• Oxygen and nutrients• Waste• Hormones

• Maintains stability of interstitial fluid

• Distributes heat

Components of Blood

• Whole Blood – includes formed elements and matrix

• Formed elements• Living blood cells• Platelets

• Nonliving fluid matrix• Plasma

Centrifuge Blood

• Plasma

• Buffy coat

• Red blood cells

Measuring Blood Samples

• Usually 45% red blood cells• Hematocrit (HTC)• Packed cell volume (PCV)

• White blood cells and platelets – less than 1%

• Clear, straw colored liquid = plasma

What is in plasma?

• Mostly water

• Also contains (every other molecule found in the human body…)• Amino acids• Protein• Carbohydrates• Lipids• Vitamins• Hormones• Electrolytes• Cellular waste

Physical Characteristics of Blood

• Opaque

• Metallic taste

• Can vary in color from scarlet (oxygen rich) to dull red (oxygen poor)

• pH between 7.35 and 7.45

• Average temperature 100.4°C

• Average human has about 5-6 liters of blood

14.2 Blood Cells

The origin of Blood Cells

• Hematopoiesis• From hematopoietic stem cells

(hemocytoblasts)

• Hematopoietic stem cells can differentiate into myeloid stem cells OR lymphoid stem cells• Determined by hematopoietic growth factors

Formed Elements

• Erythrocytes

• Leukocytes

• Granulocytes:• Neutrophils• Eosinophils• Basophils

• Agranulocytes• Lymphocytes• Monocytes

• Platelets

Erythrocytes

• Red blood cells (RBCs)

• Transport of oxygen throughout body

• Anucleate

• Few organelles

• Hemoglobin• Iron-bearing compound• Binds to oxygen

Erythrocytes

• Efficient oxygen carriers• Biconcave shape• Increases surface area• Can easily pass through small blood vessels

• Synthesis of ATP is anaerobic

• Over time, blood cells become rigid, damaged• Removal by spleen and liver

Red Blood Cell Formation

• Use your textbooks to answer the following questions:• Where does it occur?• What happens to form a mature red blood cell

from a hematopoietic stem cell?• What hormones are involved?• How long can red blood cells live?

Factors Affecting Red Blood Cell Formation

• Vitamin B12

• Folic Acid

• Both are required in DNA synthesis, mitosis

• Iron – hemoglobin synthesis

Anemia

• Decrease in oxygen carrying ability of the blood

• Can be caused by• Abnormally low number of RBCs• Abnormal/deficient hemoglobin

• Symptoms:• Pale skin• Lack of energy

Destruction of Red Blood Cells

• Damaged or worn blood cells rupture in spleen and liver

• Macrophages phagocytize RBC• Cell parts are broken down• Hemoglobin breaks into 4 globin chains• Globin chains break down into iron and biliverdin

(green)• Iron will be transferred (via transferrin) to the red

marrow to be recycled

• Biliverdin is converted into bilirubin (orange)

• Biliverdin and bilirubin are excreted in bile

Leukocytes

• White blood cells (WBCs)

• Much less numerous than red blood cells

• Body’s defense against disease

• Contain nuclei, organelles

• Differentiation and activity are controlled by • Interleukins• Colony-stimulating factors (CSF)

• 2 groups: granulocytes, agranulocytes

Granulocytes

• Leukocytes with granular cytoplasm

• About 2x the size of a RBC

• Neurophils

• Eosinophils

• Basophils

• Develop in red marrow

• Life span approx. 12 hours

Neutrophils

• Look purple with an acid/base stain

• Nucleus lobed (2-5 sections)

• First to arrive at infection site

• Phagocytosis of bacteria, fungi, some viruses

• 54% - 62% of leukocytes

Eosinophils

• Granules appear deep red in acid stain

• Two lobe nucleus

• Allergic reactions

• 1% - 3% of total number of leukocytes

Basophils

• Fewer, irregular shaped granules than eosinophyls

• Deep blue in basic stain

• Migrate to damaged tissue in response to• Histamine (promotes

inflammation)• Heparin (inhibits blood

clotting)

• Less than 1% of leukocytes

Agranulocytes

• Leukocytes without cytoplasmic granules

• Includes:• Monocytes• Formed in red marrow

• Lymphocytes• Formed in organs of the lymphatic system

Monocytes

• Largest blood cell

• Nuclei are spherical, kidney shaped or oval

• Leave blood stream and become macrophages• Phagocytize bacteria,

dead cells, other debris in tissues

• 3% - 9% of leukocytes

• Live for weeks - months

Lymphocytes

• Large nucleus with small amount of cytoplasm

• Immune cells• T cells• Directly attack microorganisms, tumors, transplanted

cells

• B cells• Produce antibodies

• 25% - 33% of leukocytes

• Live for years

Functions of WBC

• Diapedesis: leave blood vessels

• Most active: neutrophils, monocytes

• Damaged cells release chemicals to attracte leukocytes• Positive chemotaxis• Forms pus – accumulation of WBC

White Blood Cell Counts

• High count may indicate infection• Leukocytosis – number of WBC exceeding 10,000

per microliter

• Leukopenia• Low WBC count• Below 4,500 per microliter• May be caused by influenza, chicken pox, AIDS

• Differential White Blood Cell Count (DIFF)• Allows type of cell to be counted – different

diseases increase/decrease different WBCs

Platelets

• Thrombocytes

• Arise from megakaryocytes• Fragment and form platelets

• No nucleus

• Repair broken blood vessels by sticking to one another• Release of serotonin – blood vessel

constriction

Types of Blood Cell Worksheet

14.3 Blood Plasma

Blood Plasma

• Clear

• Straw-colored

• 92% water

• Functions:• Transport of nutrients, gases, vitamins• Regulate fluid and electrolyte balance• Maintain pH

Plasma Proteins

• Albumens

• Globulins

• Fibrinogen

Albumins

• 60% of plasma proteins

• Synthesized by the liver

• Osmotic pressure

• Amount of dissolved solute will determine water movement between blood and tissues

• Transport of bilirubin, fatty acids, hormones

Globulins

• 36% of plasma proteins

• Alpha globulins, beta globulins – synthesized by the liver; transport lipids and fat-soluble vitamins

• Gamma globulins – produced by the lymphatic system; type of antibody

Fibrinogen

• 4% of plasma proteins

• Largest plasma protein

• Made in the liver

• Role in blood coagulation

Gases and Nutrients

• Blood gases: oxygen, carbon dioxide, nitrogen

• Plasma nutrients: amino acids, simple sugars, nucleotides, lipids• Blood glucose levels change throughout the

days• When they are high, transported from small

intestine to liver, converted into glycogen or fat• When levels are low, glycogen is broken down

into glucose

14.4 Hemostasis

Hemostasis

• Stoppage of bleeding

• Three parts:• Blood vessel spasm• Platelet plug formation• Blood coagulation

• Occurs in smaller blood vessels

Blood Vessel Spasm

• Cutting a blood vessel results in smooth muscle within the wall of the vessel to contract (vasospasm)

Platelet Plug Formation

• Platelets adhere to any rough surface• Especially collagen of connective tissue lining

blood vessels

• Platelets will change shape to assist in adhering to other platelets

• Platelet plug will limit blood loss

Blood Coagulation

• Blood clotting

• Series of reactions form clot• Cascade

• Extrinsic (broken blood vessels, tissue damage)

• Intrinsic (blood contact with foreign substance in the absence of tissue damage)

• Blood coagulation requires different blood clotting factors

14.5 Blood Groups and Transfusions

Antigens and Antibodies

• Transfusion reactions (when a foreign substance is detected) is called agglutination• Reaction between antigens and antibodies

• Antigen: found on the surface of cells (markers)

• Antibodies: factor to fight off “other”s within the body

ABO Blood Groups

Rh Factors

• Antigen which is either present (Rh+) or absent (Rh-) on the red blood cells

• Antibody for Rh is only produced in Rh- individuals

Pregnancy and Blood Type

• Rh negative woman with an Rh positive baby• First pregnancy can be uneventful• Mother has developed little to no Rh antibodies

• Future pregnancies can have complications• Mother has developed the anti-Rh antobody due

to “exposure” from first child• Her body can try to fight off fetus• Blood transfusions are necessary in utero and

neonatally

Chapter 14 Review

• What does whole blood consist of?

• Differentiate between all blood cells.• Structure, function

• Plasma make-up and function

• Hematopoiesis

• Hemostasis

• ABO blood groups

• Antigens and Antibodies

• Rh Factor

Blood Typing Game

• http://www.nobelprize.org/educational/medicine/bloodtypinggame/

• Go to the above website.

• Type at least 10 patients.

• Describe HOW to determine blood type