UNIT 6 - CARDIOVASCULAR SYSTEM: BLOOD Flashcards
how much blood is pumped by the hearts left ventricle (per contraction)? what about per minute?
-70ml per contraction (stroke volume)
-5l per minute (whole blood supply)
what are the functions of blood?
-transportation (O2, CO2, nutrients, wastes, hormones)
-defense (WBCs phagocytize microbes or produce antibodies to disable pathogens)
-fluid loss protection (blood clotting)
-regulatory functions
what are the regulatory functions of blood?
-allows for diffusion
-maintenance of body temp
-bodys water-salt balance (maintain osmotic pressure from proteins dissolved in plasma)
-pH balance (bicarbonate in blood)
what is the standard pH of blood?
-7.4
what is the composition of blood?
-liquid CT
-composed of formed elements suspended in plasma
what are formed elements? what are the elements present in blood?
-cells and cell fragments
-RBC (erythrocytes)
-WBC (leukocytes)
-platelets/thrombocytes (cell fragments)
where are formed elements produced?
-in red bone marrow
what is the composition of plasma?
-91% water
-9% salts and organic molecules (solutes)
what is the purpose of salts and organic molecules within plasma?
-plasma proteins create osmotic pressure of blood
-solutes help maintain osmotic pressure of blood
-salts act as buffers (pH)
what are plasma proteins?
-most abundant organic molecules
-produced by the liver
-3 major proteins
what are the 3 major plasma proteins?
-albumin
-globulins
-fibrinogen
what are the characteristics of albumin?
-60% abundance
-contributes most to osmotic pressure
-binds water, cations (Ca2+, Na+, K+), hormones, thyroxine (T4) to transport within the blood
what are the characteristics of globulins?
-35% abundance
-can also be produced by the immune system
-alpha and beta globulins transport substance within the blood
-gamma-immuno globulins fight pathogens
what are the characteristics of fibrinogen?
-inactive protein
-when activated it forms blood clots
how can bloods formed elements be visualized?
-blood smear
-wright-giemsa staining
what does a wright-giemsa stain consist of?
-eosin (red dye)
-methylene (blue dye)
what percentage of our cells are RBCs?
-70%
what are the characteristics of RBCs?
-biconcave shape (increase SA + squeeze through small capillaries)
-contain hemoglobin (pigment)
what are the characteristics of hemoglobin?
-heme portion binds 4 oxygen molecules
-heme portion also can bind carbon monoxide
-globin portion can bind carbon dioxide
when oxygen is bound what is hemoglobin called? when it leaves? what about when carbon monoxide binds? what about when carbon dioxide binds?
-oxyhemoglobin
-deoxyhemoglobin
-carboxyhemoglobin
-carbaminohemoglobin
what are the 3 ways carbon dioxide is transported in blood?
-dissolved in plasma (7%)
-binds to globin of hemoglobin (23%)
-in plasma as bicarbonate (HCO3-)
what happens as RBCs are produced? what does this result in?
-lose their nucleus and most organelles
-cannot make proteins for cell repair
-cells only live ~120 days
what happens when RBCs die? how are they disposed in the body?
-removed from circulation by macrophages in the liver and spleen
what is erythropoiesis?
-the process of producing RBC
-erythropoietic stem cell to a mature RBC
what is erythropoietin (EPO)? what is its purpose?
-hormone produced by the kidneys when O2 levels in the blood are low
-stimulates the bone marrow to produce more RBCs
what is blood doping?
-increasing the number of RBCs in the body
-can be done by injecting EPO
-typically done by athletes to increase stamina and performance
what is the danger of blood doping?
-blood can become too thick causing heart failure
what is jaundice?
-accumulation of heme in the blood (dead cells) because the liver cannot excrete them
-skin and whites of eyes turn yellow
what is anemia?
-too few RBC/little hemoglobin
-various types
what are the various types of anemia?
-iron deficiency anemia
-pernicious anemia
-folic-acid-deficiency anemia
-hemolytic anemia
-sickle cell disease
what is iron deficiency anemia?
-most common form
-inadequate intake of dietary iron
-cannot make hemoglobin
what is pernicious anemia?
-lack of vitamin B12
-needed to make RBCs
what is folic-acid-deficiency anemia?
-lack of folic acid
-needed to make RBCs
what is hemolytic anemia?
-too much hemolysis (rupturing of RBCs)
what is sickle cell disease?
-genetic disease
-causes RBCs to become sickle shaped and prone to rupture (because of structure)
what are the characteristics of WBCs?
-large cells
-contain a nucleus
-translucent unless stained
-less abundant than RBCs (billion vs. trillion)
-fight infection (immune system)
-some live for days, others live months/years
what regulates the production of WBCs?
-colony-stimulating factor (CSF)
what are the 2 categories of WBCs?
-granular leukocytes (noticeable granules, lobed nuclei)
-agranular leukocytes (no granules, non lobular nuclei)
what are the types of granular leukocytes?
-neutrophils
-eosinophils
-basophils
what are the characteristics of neutrophils?
-most abundant WBC (60% of all)
-multilobed nuclei
-first responders to bacterial infections
-engulf pathogens by phagocytosis
-can leave the bloodstream (found in interstitial fluid/lymph)
what are the characteristics of eosinophils?
-about 3% of all WBCs
-bilobed nuclei
-many large granules
-functions in parasitic infections and allergies
what are the characteristics of basophils?
-rarest WBC (1% of all)
-U shaped/lobed nuclei
-with help of mast cells they release histamine during allergic reactions (in CT)
what is the purpose of histamine?
-dilates blood vessels but constricts breathing passageways (asthma attack)
what are the types of agranular leukocytes?
-lymphocytes
-monocytes
what are the characteristics of lymphocytes?
-30% of all WBCs
-2 types (T and B cells)
what is the purpose of T lymphocytes?
-directly destroy pathogens
what is the purpose of B lymphocytes?
-produce antibodies when mature
-marks a pathogen for destruction
what are the characteristics of monocytes?
-largest WBC
-develop in tissues into even larger macrophages to engulf pathogens, old cells, and debris
-6% of all WBCs
what is severe combined immunodeficiency disease (SCID)?
-an inherited disease where lymphocytes don’t develop
-bone marrow transplant can help
what is leukemia?
-a group of cancers where WBCs proliferate without control
-typically abnormal WBCs so they do not function well
what is infectious mononucleosis?
-caused by the Epstein-Barr virus
-infects lymphocytes
-results in fatigue, sore throat, and swollen lymph nodes
-transmitted by saliva
what is bubble baby disease? how is it treated?
-a deficiency in adenosine deaminase
-disturbs the function of T and B cells
-treated by regular injections of adenosine deaminase enzyme, bone marrow transplant, and gene therapy
what are platelets?
-fragments of larger cells called megakaryocytes from the red bone marrow
-not true cells (lifespan of 7-10 days)
what is the function of platelets?
-blood clotting (coagulation)
-involved with prothrombin and fibrinogen
what vitamin is necessary for the formation of prothrombin?
-vitamin K
why is blood clotting important?
-so plasma and formed elements do not leak out of broken vessels
what are the basics of clot formation?
-13 different clotting factors, calcium ions, and enzymes participate
-platelets clump to form a partial seal
-the platelets and injured tissues will release a clotting factor
-thrombin converts fibrinogen to fibrin
-fibrin forms a framework for the clot where RBCs are trapped
-fibrin clot is eventually destroyed by plasmin
-serum escapes the clot
what is the typical clotting factor? what is its purpose and what does it require?
-prothrombin activator
-converts prothrombin to thrombin
-requires calcium ions
how is fibrin used in the formation of a blood clot?
-thrombin acts as an enzyme to convert fibrinogen to fibrin
-fibrin threads provide a framework for the clot (RBCs are trapped)
-fibrin is just a temporary clot
how does fibrin act as a temporary clot? what is the reason for this?
-an enzyme called plasmin destroys the fibrin network
-so that tissue cells can grow to repair the vessel
what is serum? how is it similar and different to plasma?
-contains all the components of plasma except fibrinogen and prothrombin
what is thrombocytopenia?
-having too few platelets
-due to not enough being made in the bone marrow or increased breakdown outside of the marrow
-caused by leukemia or drugs
-symptom = excess bleeding
why would excess bleeding be a symptom of thrombocytopenia?
-lacking of the coagulation mechanism
what is thromboembolism?
-when a thrombus (stationary clot) forms, then travels (embolus), and plugs another vessel (embolism)
what is hemophilia?
-genetic deficiency of a clotting factor
-unable to form clots
what determines blood types?
-the proteins on the surface of the red blood cells
-presence and/or absence of two antigens (type A or B)
what is a blood transfusion?
-transfer of blood from one person to another
what is important concerning blood transfusion?
-blood types must be compatible
-prevents agglutination/clumping of red blood cells
why would a red blood cell transfusion be completed?
-person has experienced blood loss
-person has anemia
-person has a blood disorder
-most common type of transfusion
why would a platelet transfusion be completed?
-person has lower platelet counts
-from chemotherapy or a platelet disorder
why would a plasma transfusion be completed?
-person has experienced severe burns, infections, or liver failure
-plasma contains important proteins for health
why would a whole blood transfusion be completed?
-person has experienced a severe hemorrhage
-requires red blood cells, white blood cells, and platelets
what is an antigen?
-a foreign substance that stimulates an immune response
-often a glycoprotein (type A antigen)
what antigens are present with each blood type?
-type A (A antigen)
-type B (B antigen)
-type AB (A antigen + B antigen)
-type O (neither)
what antibodies does each blood type make?
-type A (anti-B antibodies)
-type B (anti-A antibodies)
-type AB (neither)
-type O (both antibodies)
what is specific about antibodies?
-bind only to the antigen they are made for
how is blood compatability determined?
-if the antibodies in the recipients plasma bind to the antigens on the surface of the donated red blood cells
-agglutination can occur
-crossmatch is performed to test for agglutination (mixing small amounts of blood)
what blood types are compatible?
-type A cannot receive type B or AB
-type B cannot receive type A or AB
-type O can only receive type O
what blood type is the universal donor?
-type O
what blood type is the universal recipient?
-type AB
what is the Rh factor?
-another blood type antigen
-if present blood is Rh+
-if not present blood is Rh-
what are anti-Rh antibodies also called?
-anti-D antibodies
how do the Rh antibodies develop?
-if a person is exposed to the Rh factor
what happens if a Rh- woman gives birth to a Rh+ fetus?
-some Rh+ blood can leak from the fetus to the mother
-mother will now make anti-Rh antibodies
what happens if a Rh+ mother gives birth to a Rh+ fetus?
-anti-Rh antibodies can cross the placenta and attack the fetus’ red blood cells
-could lead to anemia, disabilities, or even death
-prevented by a RhoGAM shot within 72 hours after birth
how does the Rh factor affect blood compatability?
-Rh+ can only give to Rh+
-Rh- can give to both Rh+ and Rh-
