Term
| What is the percent breakdown of the different components of blood? |
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Definition
Plasma - ~55%
White Blood Cells - ~1%
Red Blood Cells - ~40-45%
Hematocrit is defined as the RBC volume over the total volume |
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Term
| What are the main components of blood and what are their functions? |
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Definition
Plasma
-Fluid and metabolite circulation
-Maintains oncotic pressure
-Coagulation proteins, immunoglobulins
Red blood cells: carry oxygen, carbon dioxide
White blood cells: fight infection,regulate the immune system
Platelets: primary hemostatic plug |
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Term
| What are the components of blood plasma? |
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Definition
Water (90%)
Proteins
Albumin: maintains oncotic pressure, prevents water from escaping into the interstitium. It is a very important protein because water leaving would cause swelling.
Globulins: g - antibodies, b - transport proteins
Coagulation factors
Lipids - free fatty acids, cholesterol, chylomicrons
Metabolites, toxic by-products - urea |
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Term
| What are the basic characteristics of red blood cells? |
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Definition
Bi-concave disk shape
7- 8 um wide x 2 um tall - very small
5 x 10^6 per microliter
Hemoglobin gives them the red color
No nucleus
Cytoplasmic enzymes and glucose are providers of energy |
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Term
| Where does oxygen bind to the red blood cells and what element is integral in this binding? |
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Definition
Oxygen binds to the Fe (iron) center of the heme group.
Heme requires iron so an iron deficiency will cause a decrease in the amount of heme produced which will ultimately decrease oxygen transport. |
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Term
| What is the normal lifespan of a RBC? |
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Definition
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Term
| What are some regulators of RBC production? |
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Definition
RBC production or erythropoiesis is regulated by
Hypoxia (low oxygen) - RBC production increases in response to low oxygen (ex's - a smoker or at high altitude)
Erythropoietin (made by kidney) - growth factor
Increased destruction of red blood cells - to maintain levels |
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Term
| What are some inherited abnormalities of RBC's? |
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Definition
| abnormal hemoglobin, membrane proteins, or enzyme deficiencies can all lead to shortened lifespan because of increased hemolysis |
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Term
| What are some acquired abnormalities of red blood cells? |
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Definition
| abnormal production due to iron deficiency, lead poisoning, kidney failure (low erythropoietin), other toxic metabolites |
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Term
| What are the two main types of abnormal RBC size? |
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Definition
TOO SMALL = microcytosis
ex: Iron deficiency, thalassemia
TOO BIG = macrocytosis
ex. Vitamin B12 or folic acid deficiency |
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Term
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Definition
Young RBCs which have recently lost their nuclei and still have lots of RNA
Larger than average RBCs
More blue-gray in color
Sometimes folded shape |
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Term
| What do reticulocyte levels indicate? |
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Definition
High levels indicate some stress (ex - excessive blood loss)
Low levels indicate healthiness or possibly iron deficiency (remember heme and iron's role) |
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Term
| What are the examples of abnormal RBC color? |
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Definition
Normal central pallor = 1/3 of diameter of RBC
TOO PALE = hypochromia
Not enough hemoglobin
the central pallor is wider than usual
Ex: iron deficiency
TOO DARK = hyperchromia
high hemoglobin concentration due to reduced cell size
here there is no white spot or the white spot is very small.
the shape is more spherical than disk-like
can be used as a diagnosis for spherocytosis or antibody attack |
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Term
| What are the abnormal RBC shapes? |
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Definition
Spur cells (caused by renal failure)
Fragments (schistocytes) - cells are broken
Elliptocytes (caused by a mutation in spectrin) - spectrin is involved in maintaining RBC shape
Sickle cells |
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Term
| What are some abnormal inclusions that can be found in blood? |
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Definition
Nucleated RBC - looks different than a lymphocyte because it has the same color cytoplasm as a normal RBC
Nuclear remnant (Howell Jolly body) - seen after splenectomy
Basophilic stippling caused by lead poisoning
Malaria parasites |
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Term
| What are the two main types of white blood cells? |
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Definition
Granulocytes which contain granules
Mononuclear cells aka Agranulocytes - contain very little granules
-lymphocytes
-monocytes/macrophages |
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Term
| What are the different types of granulocytes? |
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Definition
Neutrophils: neutral granules - stain purple or pink
Eosinophils: red granules
Basophils: large, dark blue granules |
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Term
| What are some characteristics of neutrophils? |
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Definition
Granules stain “neutrally,” which is purplish on H&E stain
How big? 10-12 mm
Nuclei: multiple segments (3-5)
Cytoplasm: pinkish/salmon-colored
a.k.a. “polymorphonuclear leukocyte” (PMN) or “seg” - shapes can be different |
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Term
| What is the "band" form neutrophil? |
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Definition
younger neutrophil
single, U-shaped nucleus |
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Term
What is the typical neutrophil number/percentage in the blood?
What are some things that can increase or decrease that number? |
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Definition
How many? 2000-5000/microliter, 35-62% of all WBCs
Increased numbers: (granulocytosis) of neutrophils and band forms are seen in severe infections
Reduced numbers (neutropenia) may result from immunologically mediated destruction or reduced production in the bone marrow
Severe neutropenia ( < 500/ml) can lead to severe bacterial or fungal infections |
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Term
| What are some functions of neutrophils? |
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Definition
Functions of neutrophils: KILL Bacteria!
Chemotaxis: crawl and move towards bacteria Cells need to stick to tissues via cell adhesion molecules
Phagocytosis: eat bacteria
Digest: granules contain proteolytic enzymes needed to kill bacteria, oxygen radicals are produced by cytoplasmic enzymes |
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Term
| What are some examples of abnormal neutrophil functions? |
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Definition
Examples:
Abnormal oxidative burst (killing): Chronic granulomatous disease
Inability to stick to blood vessels due to mutations in adhesion molecules: Leukocyte adhesion deficiency
Abnormal function of enzymes, movement, or adhesion molecules can lead to impaired defense against bacterial infections |
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Term
| What are some characteristics of eosinophils? |
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Definition
Eosin-staining or orange-red granules
Bi-lobed nucleus
Granules contain
lysosomal enzymes
peroxidase
histamine
crystals
compared to a neutrophil there are fewer granules but the granules are much bigger
1-4% of total WBCs |
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Term
| What is the function of eosinophils? |
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Definition
| Phagocytose antigen-antibody complexes |
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Term
| What do increased numbers of eosinophils possibly indicate? |
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Definition
allergic conditions
parasitic infections
Cancers |
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Term
| What are some characteristics/functions of basophils? |
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Definition
Basophilic or blue granules, very large
0.5-1% of total WBCs
Granules contain heparin, histamine
Granule contents are released after binding of specific IgE in allergic reactions |
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Term
| What are some characteristics of agranulocytes? |
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Definition
also known as mononuclear cells they
Have single, non-segmented nucleus
Contain non-specific, azurophilic granules |
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Term
| What are some functions/characteristics of monocytes? |
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Definition
Derived from granulocyte-macrophage precursors
3-8% of total WBC
Size: 9-15 mm
Called macrophages when in found in tissues
Functions
Motile and phagocytic
Granules contain proteolytic enzymes
Produce cytokines (neutrophils don't) |
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Term
| What are some functions/characteristics of lympocytes? |
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Definition
Non-phagocytic cells
Size: 5-15 micrometer
20-45% of total WBC
Functions: B-cells
Make antibodies (immunoglobulins)
Memory cells
Plasma cells
T-cells: cellular immunity, produce lymphokines which may influence the activities of other cells
Helper (CD4) cells: enhance activity of other lymphocytes
Suppressor (CD8) cells: inhibit activity of other cells
Cytotoxic (“killer”) cells: can kill other cells on direct contact |
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Term
| What are some lymphocyte abnormalities? |
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Definition
Abnormal B-cell function
Impaired immunoglobulin production and increased bacterial infections
Abnormal T-cell function (e.g. HIV-infection)
Impaired defenses against viruses, parasites, and tumor surveillance
Increased numbers of lymphocytes may be seen with certain viral infections, e.g. varicella (chicken pox), EBV mononucleosis
“Atypical” lymphocytes may be seen in viral infections |
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Term
| What is the structure of platelets? |
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Definition
No nucleus
Do contain mitochondria and glycogen
Granules:
Alpha: contain fibrinogen, PDGF, VWF, thrombospondin, fibronectin - proteins
Delta (dense): ADP, ATP, Ca2+, serotonin - smaller molecules
Membrane adhesion molecules allow sticking to exposed basement membrane proteins and to each other |
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Term
| What are some characteristics of platelets? |
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Definition
Cytoplasmic buds from megakaryocytes in the bone marrow
How many: 150K-400K/ul
Size: 2-4 um
Lifespan: 8-10 days
Function: Activates clotting |
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Term
| How does the primary hemostatic plug work? |
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Definition
1)Injury to blood vessel exposes basement membrane proteins, such as collagen
2)Platelet activation: change shape and adhesion molecules become activated (sticky)
3)Granule contents are released to activate more platelets |
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Term
| What are some causes of abnormal platelet number? |
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Definition
Increased platelets which can cause clotting are caused by
Inflammation
Splenectomy
myeloproliferative disorders.
Reduced platelets which can cause bleeding are caused by
Increased destruction, ex. immunologically mediated
Reduced production
bone marrow malignancy
infections |
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Term
| What are some examples of abnormal platelet function? |
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Definition
Abnormal granule contents or release of contents and
Abnormal membrane adhesion molecules impair adherence to bleeding sites
Can cause excessive bleeding
also large platelets are seen in conditions which stimulate increased production |
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Term
| What are the characteristics of coagulation proteins? |
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Definition
Circulate in plasma in inactive proenzyme form
Active forms are proteolytic except for fibrin
Most are made in liver, except Factor VIII, vonWillebrand factor: produced by endothelial cells and megakaryocytes |
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Term
| What are coagulation disorders? |
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Definition
There are inherited deficiencies of all of the proteins in the coagulation cascade which cause increased bleeding
Ex: Hemophilia A = Factor VIII deficiency
Hemophilia B = Factor IX deficiency |
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Term
| Describe the symptoms and causes of anemia |
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Definition
Cause - too few RBCs
symptoms - tiredness |
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Term
| Describe the symptoms and causes of polycythemia |
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Definition
Cause - too many RBC's
symptoms - slow blood flow |
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Term
| Describe the symptoms and causes of neutropenia |
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Definition
Cause - too few WBC's
symptom - infections |
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Term
| Describe the symptoms and causes of leukemia? |
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Definition
Cause - too many WBC's
symptoms - organ enlargement |
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Term
| Describe the symptoms and causes of thrombocytopenia |
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Definition
Causes - too few platelets
symptoms - excessive bleeding |
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Term
| Describe the symptoms and causes of thrombocytosis |
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Definition
Cause - too many platelets
symptom - excessive clotting |
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Term
| Describe the symptoms and causes of bleeding disordes |
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Definition
cause - too little coagulation proteins
symptom - excessive bleeding |
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Term
| What does antibody deficiency cause? |
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Definition
| Increased bacterial infections |
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Term
| What does excessive antibodies cause? |
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Definition
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