Blood Flashcards
What are the components of the plasma of the blood?
- water (mostly,90%)
- Ions
- Organic molecules (amino acids, proteins, glucose, lipids, nitrogenous waste)
- Proteins include: albumins, globulins, fibrinogen, transferrin
- trace elements and vitamins
- gases: CO2 and O2
What is the function of albumin?
- regulate blood pressure
- use as a carrier to transport hydrophobic molecules
What process creates blood?
Hemaopoiesis
Where is blood produced?
- red bone marrow
- along axial skeleton
Can yellow bone marrow be reconverted back into red bone marrow?
Yes
Erythropoiesis influences the growth of what?
-red blood cells
Which hormone is responsible of making RBC?
- erythropoietin (EPO)
- produced in the kidney cells
Thrombopoeitin travels to the red bone marrow to stimulate what?
- megakaryocytes
- produce primarily in the liver
What is the function of Thrombopoiesis?
-influence the growth of megakaryocytes that are responsible for the production of blood platelets
What is the function of Leukopoiesis?
-produce white blood cells
What stimulates the process of Leukopoeisis?
Colony-stimulating factors, interleukins
What is the parent cell of all the blood cells (white/red)?
-pluripotent hematopoietic stem cell
What determines the path of the uncommitted stem cells?
- Erythropoietin (EPO)
- Thrombopoietin (TPO)
- Colony stimulating factors
Where are -pluripotent hematopoietic stem cell found?
Red bone marrow
What is the function of the hematocrit test?
%’s M vs F
% of RBC in total blood volume
- Females: 37-47% - males: 40-54%
Structure of the erythrocytes
- no organelles
- bi-concave shape: allows travel through capillaries
- use anaerobic respiration
What is the normal size of a red blood cell?
-80-96 fL (femotoliter)
What is required for the synthesis of hemoglobin?
- Iron (Fe)
Explain the synthesis and destruction of hemoglobin
What is the average life cycle of an RBC?
-120 days
What is anemia?
-total circulating RBCs below normal limits
What are the symptoms of Anemia during accelerated RBC loss?
- blood loss
- hemolytic anemias: cells rupture at an abnormally high rate
- abnormal hemoglobin: ex. Sickle cell anemia
- parasitic infections: ex. Malaria
What are the symptoms of Anemia during decreased RBC production?
- aplastic anemia
- iron deficiency (Fe required for heme production)
- folic acid deficiency (F.A required for DNA synthesis)
- Vit B12 deficiency ( Vit B12 required for DNA synthesis)
- inadequate production of erythropoietin (needed to stimulate red bone marrow to created RBC)
What is Polycythemia Vera?
-abnormally high blood cell count
What happens when hemostasis occurs?
- vasoconstriction (constricts blood vessel)
- reduce blood flow
- platelet activation
- blood clotting
What is hemostasis?
-the stopping of blood flow
What is the role of serotonin during hemostasis?
-its a vasoconstrictor
How is thromboxane A2 produced In a damaged blood vessel? Function?
-vasoconstrictor, increases platelet aggregation
What are the different platelet function factors? (6)
- serotonin (vasoconstrictor)
- ADP
- Platelet activating factor: activates more platelets and produces thromboxane a2
- thromboxane A2
- collagen
- platelet derived growth factor
What is the function of the coagulation cascade?
-formation of solid clots
What are the two pathways of coagulation cascade?
- intrinsic pathway (contact activation)
- Extrinsic pathway (cell injury)
Where are the clotting factors synthesized?
-made in the liver
What are the factors involved in coagulation? (6)
- collagen
- tissue factor (thromboplastin or factor III)
- prothrombin and thrombin
- fibrinogen and fibrin
- Ca2+
- Vit K
What is the process of fibrinolysis?
-dissolution of clot by plasmin
During blood clotting prevention, what does the endothelium of a healthy blood vessel secrete?
- prostacyclin and NO (nitric oxide; a vasodilator)
- inhibits platelet aggregation
How is prostacyclin synthesized in a health blood vessel? Function?
-vasodilator, inhibits platelet aggregation
What is the role of prostacyclin in a healthy blood vessel?
- vasodilator
- inhibits platelet aggregation
What are the roles of anticoagulants
-block clotting factors
What are the different types of anticoagulants?
Block clotting factors
- heparin
- antithrombin III
- protein C
- vitamin K antagonist
- aspirin (inhibits COX1)
What are the causes of hemophilia?
-defective or lacking clotting factors (VIII or IX)
What are the cellular elements found in the blood?
- RBCs
- WBCs
- lymphocytes
- monocytes
- neutrophils
- eosinophils
- basophils
-platelets
What is the pathway of a pluripotent hematopoietic stem cell to a erythrocyte?
pluripotent hematopoietic stem cell > Uncommitted stem cells > Committed progenitor cells > Erythroblast > Reticulocyte > Erythrocyte
Which protein transports Iron (Fe) in plasma?
Transferrin proteins
Old RBCs are converted into what? (Destruction of hemoglobins)
- bilirubin (process occurs in the spleen)
- is eventually metabolized in the liver and excretes it in bile
- can also be excreted in urine and feces
