Blood Flashcards
Know the normal pH and volume of blood in the human body
The normal pH is 7.35-7.45 and there is 4-5L in females and 5-6L in males. We say 5L is around normal.
Know the components of blood. Include WBC’s, RBC’s platelets, and the major components of plasma.
The blood’s cellular components contain red blood cells, white blood cells, and platelets.
-RBC (erythrocytes) contain Hemoglobin which carries O2 and are a major contributor to blood viscosity by controlling Hematocrit
-WBC (Leukocytes) function in the immune response
-Platelets are cell fragments that function in blood clotting
The plasma portion consists of water, proteins and other solutes.
Know the functions of blood.
1st Function:
-Blood transports: gases (O2, CO2), nutrients (glucose), hormones, wastes (urea, ammonia), electrolytes (Na+, K+, Ca+, Cl-) heat
2nd Function:
-Blood regulates homeostasis of all body fluids: pH electrolyte balance, osmotic pressure, blood buffer, temperature (vasodilation/vasoconstriction, water in plasma)
3rd Function:
-Blood protects against excessive loss by restricting fluid loss at injury by clotting and uses white blood cells to protect against infections
Know the plasma proteins, job, and where most are synthesized. Why would the level of albumin in the blood be lower in patients with liver disease.
Albumin functions to maintain blood colloid osmotic pressure that is key for capillary exchange. Patients with liver disease would have low levels of albumin because of the decreased synthesis by the hepatocytes as well as water and sodium retention
Globulins are transporters for lipids including the fat soluble vitamins (which are ADE and K) and gamma globulins. They also carry and sequester some ions:
- Transferrin transports Fe2+
-Transthyretin transports thyroxine
-Transcortin transports ACTH
Fibrinogen is the inactive form of fibrin and is activated during the blood clotting cascade
Regulatory proteins in the blood include enzymes and hormones
Immunoglobins attack virus bacteria etc.
Know the structure and components of RBC’s. Know why RBC’s have their disc like structure.
RBC contain the protein hemoglobin that is used to carry oxygen to all cells and carry some carbon dioxide to the lungs. The membranes identify the ABO and Rh blood groups. RBC do not contain a nucleus or other organelles and are biconcave discs in order to carry oxygen more efficiently with a high surface to volume ratio. Bend flex and stack through capillary network and are removed every 120 days by the spleen.
Describe the structure and functions of hemoglobin
Hemoglobin contains and iron ion which allows each molecule to bind four oxygen molecules. Heme portion carries O2. Hb also carries NO (nitric oxide) which regulates blood flow and blood pressure. NO causes vasodilation which improves blood flow and enhances oxygen delivery.
Know the effects of hematocrit with blood pressure
A high hematocrit indicates high blood viscosity which can increase blood pressure.
Be able to describe erythropoiesis. What is erythropoietin and what is its function? Why do kidney dialysis patients become anemic? What do you need in your diet for erythropoiesis to occur? Know how erythropoiesis is regulated.
Erythropoiesis is the production of red blood cells and begins in the red bone marrow. Erythropoietin (EPO) is a hormone released by the hormones in response to lowered oxygen concentration stimulating differentiation of hematopoietic stem cells into erythrocytes. Dialysis patients become anemic because their kidneys do not make enough EPO. In order for erythropoiesis to occur, you need iron, vitamin B12, and folic acid. Erythropoiesis is regulated by hemopoietic growth factors which regulates differentiation and proliferation of erythropoietin.
Be able to describe Hemopoiesis and how it is regulated. Know where blood cells originate. Define proliferation and differentiation in Hemopoiesis. Know the basic pathway of blood cell formation
Hemopoiesis is the differentiation and maturation of all blood cells, not just red blood cells. It is regulated by the Hemopoietic growth factors that regulate differentiation and proliferation. All blood cells originate from a Pluripotent stem cell.
Blood cell formation pathway (ppt):
-Pluripotent Stem Cell to Myeloid stem cell, lymphoid stem cell
-Myeloid Stem cell to a blast cell
-Lymphoid stem cell to a lymphoblast
-Blast cell to reticulocyte, megakaryocyte, WBC, Blasts
-Then to RBC, Platelets, Eosinophil, Basophil, Neutrophil, monocyte.
-From lymphoblast to T cell, B cell, NK
Be able to explain how RBC’s are destroyed/recycled. Know the pathways of hemoglobin breakdown and the end products.
Broken down by macrophages in the spleen, liver, and red bone marrow. Breakdown products recycled. Iron is converted to ferritin and stored in the liver and bone by transferrin. Globin protein as broken down into amino acids which can be reused to build more proteins. Heme breakdown produces multiple products.
Hemoglobin breakdown:
-Biliverdin (green)
-Bilirubin (liver)
-Bile
-Sm. Intestine to blood stream then to Urobilin (urine yellow)
-Lg. Intestine
-Metabolism (bacteria)
-Stercobilirubin (feces brown)
Be able to name the white blood cells and know their functions. Know the approximate amounts (Never Let Monkeys Eat Bananas) of these cells in a “normal” blood smear
-Neutrophils (60-70%) Active phagocyte, attracted by chemotaxis, first on scene, short lived, Use lysosomes, strong oxidants, defensins
-Lymphocytes (20-25%) Major soldier of the immune system, B-cells (bacteria), T-cells (virus, fungus, cancer cells, some bacteria) NK cells (Microbes, Tumor cells)
-Monocytes (3-8%) Active phagocyte, attracted by chemotaxis, Differentiate into macrophages, fixed group found in specific tissues, alveolar macrophages in lungs, Kupffer cells in liver, wandering group gathers at sites of infection
-Eosinophils (2-4%) Leave capillary, release: Histamine, phagocyte antigen-antibody complex, Effective (parasitic worms etc.)
-Basophils (.5-1%) Leave capillaries, intensify inflammation, release histamine and serotonin, involved in allergies and hypersensitivity, inhibit blood clotting, release heparin
Be able to describe emigration of WBC’s out of the blood
When there is a virus in the body, WBC leave the bloodstream and collect at sites of invasion. They roll along the endothelium. Stick together and squeeze between endothelial cells to leave the capillary and enter ISF. The precise signals vary for the emigration of different types of WBC.
Describe the structure and function of platelets
Platelets are used to clot the blood. Megakaryocytes in red bone marrow splinter into 2000-3000 fragments to create platelets that contain many vesicles but no nucleus. Inactive platelets are not sticky, activated platelets are stick to form a platelet plug.
Know hemostasis can occur using one or more of these processes: vascular spasms, platelet plug formation and coagulation
Hemostasis is a cascade of enzymatic reactions that end with the formation of fibrin. can occur using one or more of; vascular spasms, platelet plug formation and coagulation.
Be able to describe the role of vascular spasm
Vasoconstriction of arteries and arterioles seals off blood as circular smooth muscle constricts in response to damage to the smooth muscle or substances released by activated platelets. Pain receptor reflexes can also stimulate vascular spasm.
