Unit 3 Flashcards
What does whole blood consist of?
Formed elements, plasma proteins, and solutes
What are formed elements in the blood?
WBC’s, RBC’s, and platelets
What kinds of solutes are in the blood?
Electrolytes, gases, nutrients, and waste products
What lies between RBC’s and Plasma in centrifuged blood?
Buffy coat (WBC’s and platelets)
What percentage of whole blood is plasma?
55% to 60%
What percentage of whole blood is RBC’s?
45%
Plasma vs. Serum
Plasma is unclothed blood, while serum is already clotted
How much of plasma is water?
92%
How much of plasma is solutes?
8%
What percentage of solutes in the plasma are plasma proteins?
7%
Identify 3 plasma proteins in blood plasma
Albumin, globulin, and fibrinogen
What does the last 1% of plasma consist of?
Other solutes like electrolytes, nutrients, gases, hormones, and wastes
Where is albumin synthesized?
The liver
What does albumin do?
Contributes to blood viscosity (thickness) and maintains blood pressure
Where is albumin found?
In the capillaries; it can not diffuse freely across the vascular endothelium
What is the function of albumin?
Acts as an osmotically-active carrier molecule for oxygen by binding to hemoglobin
What are globulins?
There are 4 main groups of globulins; alpha, alpha2, beta, and gamma
What are alpha globulins responsible for?
Carrier molecule
What are beta globulins responsible for?
Carrier molecule
Do alpha and beta globulins interact?
Yes, together they control blood osmotic pressure
What is the responsibility for gamma globulins?
Immunity; immunoglobulins or antibodies; they are made by plasma cells and are activated B lymphocytes
What electrolytes can be found in the plasma?
Na, K, Cl, HCO3, Ca, and lots more
List an example of a blood gas that would be found in the plasma?
Oxygen or CO2
What is an example of a waste product found in the plasma?
Uric acid, bilirubin, creatinine (see how the kidneys are working), and urea (blood urea nitrogen from a protein)
What is another name for RBC’s?
Erythrocytes
What is the lifespan of a RBC?
80 - 120 days
What is the function of a RBC?
Gas transport; carry oxygen and CO2 –> HCO3
What is unique about RBC’s?
They have a biconcave shape, which increases it’s surface area and allows it to have reversible deformity
Define hematocrit (Hct)
Percent of whole blood volume occupied by red blood cells
What is hematocrit percent for males?
40 -54%
What is the hematocrit percent for females?
38-46%
Define hemoglobin
Oxygen-carrying molecule consisting of 4 heme + 4 glob in proteins + 1 Fe molecule
What is the average volume of hemoglobin in the blood?
14-16 g/dL
What is the normal number of RBC’s in the blood?
4-6 X 10^6 mm3; million
Define mean corpuscular (cell) volume (MCV)
Volume of an average RBC; measured in fL (femtoliters)
Define mean corpuscular (cell) hemoglobin
Amount of hemoglobin in an average RBC; measured in pg (picograms)
Define mean corpuscular (cell) hemoglobin concentration
Concentration of hemoglobin in an average RBC; measured in g/dL (Hgb/volume)
Define anemia
Decrease in RBC’s
Define polycythemia
Abnormal increase in RBC’s
What would cause someone to increase RBC’s and still have it be in the “normal” range?
Exercise or being at a higher altitude
What organ recycles RBC’s?
The spleen
Describe the development of RBC’s
Begin with a nucleus, then the nucleus is kicked out and the cell is now a reticulocyte, and then it matures into a RBC
Define reticulocyte
An immature RBC containing hemoglobin, RNA, and mitochondrial remnants
Define microcytic
Smaller than normal cell
Define macrocytic
Larger than normal cell
What does chrom- mean?
Color
Define hypochromic
Color is lighter than normal
Define normochromic
Color is normal
What are indices?
MCV, MCH, and MVHC
What is another name for a WBC?
Leukocyte
What is the average range of WBC’s in the blood?
5-10 X 10^3/ mm3; Thousands
What are the two categories for WBC’s?
Granulocytes and agranulocytes
What types of WBC’s are granulocytes?
Neutrophils, eosinophils, and basophils
What is the lifespan of granulocytes?
1/2 day to 9 days; most die doing their jobs
Which types of WBC’s are agranulocytes?
Lymphocytes and monocytes
What is the lifespan of a granulocytes?
Lymphocytes live forever (days to decades) and monocytes live for months
Define leukocytosis
Increase is WBC count
What is leukocytosis caused from?
Viral and bacterial infections; body normal response to disease up to a certain point
Define leukopenia
Decrease in WBC count; never normal
What do neutrophils look like?
Pinkish cytoplasm with a segmented nucleus
What is the function of a neutrophil?
Fight bacterial infections; phagocytic cells that quickly respond to disease
What is the concentration of neutrophils in the blood?
60% to 70%
What do eosinophils look like?
Large red granules with nucleus pushed to one side
What is the function of an eosinophil?
Target antigen-antibody complexes involved with allergies and parasites
What is the concentration of eosinophils in the blood?
1% to 4%
What do basophils look like?
Large dark blue granules
What is the function of a basophil?
Participate in inflammatory responses; release histamine and heparin
What is the concentration of basophils in the blood?
0% to 1%
What do monocytes look like?
Large segmented nucleus that takes up most of the cell
What is the function of a monocyte?
It’s a immature macrophage that wanders to different tissue sites and then matures into a powerful phagocytes; gets it name due to the tissues it matured in.
What is the concentration of monocytes/macrophages in the blood?
3% to 8%
List some examples of macrophages
Kupffer cells = liver, histiocytes = tissue, microglial = nervous, alveolar = lungs
What do lymphocytes look like?
Large nucleus the size of the cell
What is the function of lymphocytes?
Fight viral infections using adaptive immunity with two types of cells; T cells and B cells
What is the concentration of lymphocytes in the blood?
They are actually all contained in the lymph, but they account for 20% to 30% of all WBC’s
What is the lymphatic system?
System consisting of organs and lymph vessels through which lymphatic fluid passes
What is the function of the lymphatic system?
Drain interstitial fluid, transport dietary lipids absorbed by the GI tract to the blood, and facilitate an immune response
What are the primary lymphoid organs?
Thymus and bone marrow
What is the main function of the primary lymphoid organs?
Production
What is the bone marrow responsible for? Thymus?
Bone marrow makes cells that mature into B cells. The thymus take cells from the bone marrow and mature them in to T cells
What are the secondary lymphoid organs?
Spleen, lymph nodes, tonsils, and peyer patches of the small intestine
What do the lymph organs do?
Link the hematologic and immune systems
What comprises the lymphatic system?
Lymph vessels, lymph nodes, right and left lymphatic ducts, tonsils, spleen, thymus, and bone marrow
What does the spleen do in the lymphatic system?
Fliters and cleanses the blood- removes old or damaged cells; storage area for extra blood (up to 1/3)
What is the main function of the lymph nodes?
Filters the lymph
Name the important groups of lymph node
Submandibular, cervical, axillary, and inguinal
What is hematopoiesis?
Cells are formed in red bone marrow from pluripotent stem cells and mature in the bone marrow or lymphoid tissue (spleen, thymus, tonsils, and lymph nodes)
What type of cells increase hematopoiesis?
Cytokines
What are the two types of stem cells that come from pluripotent stem cells?
Myeloid and lymphoid (lymphocytes)
Define medullary hematopoiesis
Cellular production in the bone marrow
Define extramedullary hematopoiesis
Production outside of the bone marrow (liver, spleen) caused by disease
What is erythropoiesis?
Production of RBC’s
What organ is stimulated by hypoxia to generate erythropoiesis?
Kidneys
What are the steps of erythropoiesis?
- Kidneys are stimulated by hypoxia
- Kidneys release hormone erythropoietin (EPO)
- Erythropoietin circulates the red bone marrow and speeds up the maturation of immature RBC’s
What is an immature RBC?
Reticulocyte
Is the rate of erythropoiesis reflected in the rectiulocyte count?
Yes as you increase reticulocytes you increase RBC’s
What does a retic contain?
Hemoglobin, RNA, and mitochondrial remnants
What do hematopoietic cells need to develop and differentiate?
Growth factors
What are colony stimulating factors (CSF)?
Cytokines that act as hormones to stimulate proliferation of early cells; necessary for growth of myeloid, erythroid, lymphoid, and megakaryocytic cells
List a few growth factors involved with hematopoiesis
GM-CSF, G-CSF, and EPO
Where do G-CSF come from? what cells do they stimulate?
Macrophages and fibroblasts; stimulate granulocytes
Where do GM-CSF come from? What cells do they stimulate?
T cells; stimulate neutrophils and macrophages
Where do EPO come from? What cells do they stimulate?
Kidney cells and Kupffer cells; stimulate erythrocytes
What are platelets?
Cell fragments that originated from megokaryocytes
What do platelets do?
Aid in the clotting by clumping and the release of biochemical mediators
Define thrombocytopenia
Low platelet count
Define thrombocytosis
Increased platelet count
What are the three steps in hemostasis?
- Vascular spasms; involuntary
- Platelet plug formation
- Activation of the coagulation cascade (fibrinogen –> fibrin mesh)
Is the clotting cascade positive or negative feedback?
Positive feedback
How does the clotting cascade start?
Activation of several soluble, inactive clotting factors stimulated in a cascading fashion
What are the two pathways in the clotting cascade?
Extrinsic pathway and intrinsic pathway
Where do the extrinsic and intrinsic pathway meet up?
Common pathway converge at factor X
What is the extrinsic pathway activated by?
Tissue factor (tissue thromboplastin)
What is the intrinsic pathway activated by?
Contact with the injured vessel; collagen and endothelium
What ion plays a role in coagulation?
Ca2+
What are the stages of coagulation?
- Extrinsic and intrinsic activation
- Common pathway begins with formation of prothrombinase (prothrombin activator)
- Prothrombin activator activates prothrombin to thrombin
- Thrombin induces the formation of fibrin from fibrinogen
What is clot retraction?
After 30 - 60 minutes the platelets contract, the plot becomes impacted and the edges of the blood vessel are brought closer together; healing is starting and clot needs to be removed
How do the platelets contract?
They contain actin and myosin proteins that squeeze out the serum
What is going on during healing?
Smooth muscle cells and fibroblasts are stimulated to divide
How is the clot removed?
Fibrinolysis
What system is responsible for clot breakdown?
Fibrinolytic system
What are the steps to clot breakdown?
- Endothelial cells produce tissue plasminogen activator (TPA) which causes plasminogen –> plasmin
- Factor Xll and thrombin in coagulation cascade also change plasminogen –> plasmin
- Plasmin digests clots
Where is bone marrow biopsy taken from?
Posterior iliac crest
What does a bone marrow biopsy do?
Helps diagnose anemias, leukemias, platelet disorders, immunoglobulin disorders, etc
List complete blood count tests
WBC count, WBC differential, RBC count, hemoglobin, hematocrit, platelet count, MCV, MCH, MCHC, and RDW (red cell distribution width)
Tests for WBC differential
Bacterial appendicitis = neutrophils, infectious mono - Epstei-Barr virus = lymphocytes, and chronic lymphocytic leukemia (CLL) = lymphocytes
Coagulation tests
Prothrombin time/international normalized ratio (PT/INR), activated partial thromboplastin time (APTT), and bleeding time
