Peripheral Blood Flashcards
What are formed elements?
- Red blood cells
- White blood cells
- Platelets
What does blood consist of?
- Formed elements
- Plasma
What cells make up leukocytes?
- Neutrophils
- Lymphocytes
- Monocytes
- Eosinophils
- Basophils
What is Hematocrit?
-The volume occupied by RBC’s after centrifugation of a sample of blood
What is the average hematocrit for men and women?
Men: 40-50%
Women: 35-45%
What percentage of blood is plasma?
-50-65%
What makes up plasma?
- Water
- Proteins
- Electolytes & solutes
What do blue top blood tubes contain? What are they used for?
- anticoagulant
- Used for sedimentation rate (ESR)
How many red blood cells are there per microliter of blood?
-5 million
What is sedimentation rate? (ESR)
-the time needed for RBC’s to settle to the bottom of a blue capped test tube
What are the red-top blood tubes for?
-determining clotting time
What does the clot consist of?
- formed elements
- clotting factors
What is contained within serum?
- Growth factors
- proteins
- antibodies
- proteins released from platelets
What is the diameter of a normal red blood cell?
-7.5 um
How do red blood cells derive energy?
-anaerobic metabolism of glucose
What are the basic constituents of the red blood cell membrane?
- 40% lipid
- 50% protein
- 10% oligosaccharide
What determines the blood type of a patient?
-oligosaccharides on the surface
What cytoskeleton do red blood cells have?
- band proteins w/ ankyrin
- connected by spectrin to actin link piece
What are the 3 sites of normal red blood cell destruction?
- spleen
- liveer
- bone marrow
How are old red blood cells recognized?
- alteration of surface oligosaccharides
- dysfunctional ion channels
- changes in cytoskeleton
What are reticulocytes?
- immature RBC’s
- contain small amounts of remnant mRNA and ribosomes
- normally 1% of peripheral RBC’s
What is reticking?
- when >1% of peripheral RBC’s are reticulocytes
- signifies loss of RBC’s
What is Polycythemia?
-Increased Hematocrit
What does Polycythemia increase the risk of?
-thrombotic events
What are the general causes of anemia?
- blood loss
- decreased RBC production
- Increased RBC destruction
- Production of RBC’s with low Hb content
What diameter is associated with a macrocyte?
-RBC with diameter >9 um
What causes microcytic anemia?
- decreased Hb synthesis during erythrocyte dev
- caused by low Fe
What is hereditary spherocytosis?
- patients have fragile, convex RBC’s
- caused by mutation in ankyrin
What is the Buffy Coat?
-portion of blood that contains platelets and leukocytes
List the granulocytes of the Buffy coat:
- neutrophils
- Eosinophils
- Basophils
List the agranulocytes of the Buffy coat:
- Monocytes
- Lymphocytes
What are Azurophilic Granules?
- specialized lysozomes that stain darkly.
- present in all granulocytes
Where is granule synthesis complete?
-Bone marrow
What kind of nucleus does the Neurtrophil have?
-tri-lobed
What kind of nucleus does the Eosinophil have?
-Bi-lobed
What kind of nucleus does the Basophil have?
- Bi-lobed
- Difficult to see though b/c of staining
What do neutrophils do?
-kill bacteria
What is a drumstick appendage?
-the inactivated X chromosome seen protruding from the nucleus of neutrophils in femails
How do neutrophils create energy?
-anaerobic metabolism of glucose
What is pus?
- dead bacteria
- neutrophils
What does lactoferrin do?
- binds iron
- iron is crucial to the survival of bacteria, take it away with lactoferrin, bacteria die
Describe hereditary neutrophil disorder:
- deficiency of NADPH oxidase
- reduces killing power of neutrophils as they cannot produce hydrogen peroxide
What is left shift?
- means antibiotics aren’t working
- band cells seen in blood smear
What are Band Cells?
-immature Neutrophils
What is the distinguishing characteristic of band cells?
-Horseshoe shaped nucleus
What signal on the surface of endothelial cells tells neutrophils and leukocytes where to slow down and enter tissue from the blood stream?
-P-selectin
What is diapedesis?
-migration of leukocytes into the tissue surrounding blood vessels
What do Eosinophils do?
- kill parasites
- also produce substances that counteract basophils and mast cells
What is major basic protein in Eosinophils?
- used to kill parasites
- eosinophil surrounds worm and exocytoses MBP to kill them
How do Eosinophils kill their targets?
-surround them and exocytose MBP
What do Basophils do?
-release heparin and histamine in response to IgE antibodies
What receptors are Basophils coated with?
-IgE
What are the three types of lymphocytes based on cell surface markers?
- T Lymphocytes (CD 4+/8+)
- B Lymphocytes (CD 20+)
- Natural Killer Cells
Are Lymphocytes terminally differnetiated upon leaving the bone marrow?
-No
What are the only leukocytes that can return from the tissue back to the blood after diapedesis?
-Lymphocytes
What are the largest leukocytes?
-Monocytes
What is the shape of the monocyte nuclesu?
- Large
- Oval
- Horeseshoe
- kidney
What do monocytes do?
- precursor cells of the mononuclear phagocytic system
- become APC’s in other tissues (macrohpages, laangerhans, etc)
What do platelets tend to do in peripheral blood smears?
-clump together
What is the normal range of platelets found per uL of blood?
-120,000-400,000
What is the lifespan of platelets?
-10 days
What are demarcation areas?
-mark where platelets will separate from megakaryocyte
What is the hyalomere of a platelet?
-lightly staining peripheral zone
What is the granulomere of a platelet?
-darker staining central zone
What is found within the granulomere?
- Actin/myosin (contractility)
- granules
What are the granules of platelets?
- Lambda
- Delta
- Alpha
What are lambda granules?
-lysosomes
What are Delta Granules?
-contain ATP, ADP, PPi, 5-HT, & calcium
What are Alpha granules?
-contain fibrinogen and other platelet recruiting factors
What does the open canalicular system do for platelets?
- provides a large surface area onto which granules can fuse
- consist of invaginations of the plasma membrane deep into the platelet
What does the dense tubular system do for the platelet?
-Stores Ca2+ ions
What are the major roles of platelets in clotting?
- primary aggregation
- secondary aggregation
- blood coagulation
What is clot retraction?
-clot bulging into the blood vessel lumen contracts due to the interaction of platelet actin and myosin
What are the two systems of membrane channels in platelets?
- Open canalicular system
- Dense tubular system
