anatomy and physiology biology 2122k floyd college
TRANSCRIPT
Course Syllabus
http://www.floyd.edu/academics/divisions/smpe/biology/jhargettOr go to:www.floyd.edu and follow links to
academics, science & math, biology, adjuncts, Hargett
BLOOD Liquid connective tissue
comprising 8% of body weight 4-5 times more viscous than water,
salty Volume - 4-6 liters
8-12 pints
FUNCTIONS Transportation - oxygen, CO2, nutrients,
hormones and wastes
Protection - have cells that phagocytize bacteria and produce antibodies; clotting mechanisms that prevent blood loss
Regulation - pH, body temperature,water content
Components of Blood PLASMA - is the liquid portion of the blood and
consists primarily of water (92%) and plasma proteins (7%)
Proteins - albumin, globulins, and fibrinogen FORMED ELEMENTS - solid component of the
blood consisting of erythrocytes, leukocytes, and platelets
BLOOD = 55% plasma + 45% formed elements
Types of Cells Erythrocytes - Red Blood Cells
Carry oxygen Leukocytes - White Blood Cells
Immunity Thrombocytes – Platelets
Blood Clotting
Erythrocytes Very flexible, biconcave disk lacking a
nucleus Most numerous of cells; 5million/mm3
Transport respiratory gases such as oxygen and carbon dioxide
Approximately 120 day life span Hemoglobin - Consists of 4 polypeptide
globin chains with a heme molecule in each one Each hemoglobin molecule can carry four
oxygen molecules
Types of Tests Red blood cell count –
4.3 – 5.8 million/mm3
Hemoglobin – 11.8 – 15.9 g/dl - Females 13.8 – 18.4 g/dl - Males
Hematocrit - 35-47% in Females 41-54% in Males
Reticulocyte – measures rate of RBC production
Hematopoiesis Occurs in red marrow Produces 1 oz. (100 billion cells) /day Stem cells called hemocytoblasts produce all
types of blood cells. Erythropoiesis:
Hemocytoblast (stem cell) Proerythroblast Erythroblast (large numbers of ribosomes
produce hemoglobin and store iron) Normoblast - loses nucleus and organelles Reticulocyte - immature (still contain E.R.) Erythrocyte - full process = 5-7 days
Hormonal control of blood production Erythropoietin
Produced by kidneys & liver Production due to:
Reduced RBC count Reduced oxygen availability Increased tissue demands
Leukocyte - WBC Granulocytes -
Neutrophils - phagocytize bacteria (60-70%);
Eosinophils - associated with allergic reactions and parasitic infections (2-4%)
Basophils - involved in the inflammatory response as well as allergic reactions; granules contain heparin and histamine (0.5-1%)
Agranulocytes - play a crucial role in immunity Monocytes - phagocytic macrophages
(3-8%) Lymphocytes - involved in immunity;
B cells and T cells (20-25%)
Thrombocyte - Platelet
Cytoplasmic fragments that are essential in blood clotting; help form a platelet plug
Platelets have a life span of only 5-9 days
Normal platelet count :250,000-400,00/mm3
Stages of blood clotting
Vascular spasms - blood vessel constriction
Formation of a platelet plug - platelets stick to each other and the collagen exposed in the damaged tissue to form a plug
Coagulation - formation of a clot
Coagulation
Involves two chemical, enzymatic pathways resulting in the conversion of soluble fibrinogen into insoluble fibrin
Extrinsic pathway - cell trauma releases TF Intrinsic pathway - all components in blood Thirteen clotting factors involved; most are
produced in the liver Vitamin K dependent - II, VII, IX, X
Stages of blood clotting
Formation of prothrombinase (prothrombin activator)
Conversion of prothrombin to thrombin
Conversion of soluble fibrinogen into insoluble fibrin
Factor (procoagulants) sequence
12 - Hageman (glass) Factor 11 - Plasma thromboplastin antecedent 7 - Serum prothrombin conversion
accelerator 4 - Calcium ions 9 - Plasma thromboplastin component 8 - Antihemophilic factor 10 - Stuart Factor (thromboplastin)
Coagulant Factor Sequence (con’t)
10 - Stuart Factor 4 - Calcium Ions 3 - Tissue Factor 5 - Proaccelerin 2 - Prothrombin Thrombin
1 - Fibrinogen Fibrin 13 - Fibrin stabilizing factor
Forms
prothrombin
activator
Coagulation
Normal coagulation involves: normal platelets clotting factors vitamin K calcium
Clot Retraction - contractile proteins tighten clot
Fibrinolysis - clot dissolves
Clotting Disorders Thrombus - stationary clot
Embolus - circulating clot
Thrombocytopenia - deficient number of platelets
Hemophilia - genetic bleeding disorder
Hemophilia 3 types Hemophilia A (classical) - lack of factor VIII. Hemophilia B - lack of factor IX Hemophilia C - lack of factor XI Types A & B are sex-linked recessive.. Appeared in the royal families of Europe,
beginning with the children of Queen Victoria
Blood Groups - Typing
Blood is typed into groups depending upon the type of agglutinogens (antigens) present on the red blood cell surface
The plasma may contain genetically determined agglutinins or antibodies against the blood group antigens that they DO NOT have
The ABO and Rh system are based upon antigen-antibody type responses
Blood Typing ABO system - people who posses the A
antigen on the RBC surface are type A; if you posses the B antigen you are blood type B; if both A and B are present you are type AB; if neither A or B antigens are present, your blood type is O
Type O - universal donor, can give blood to anyone
Type AB - universal recipient, can receive blood from any blood type
Rh system - individuals whose red blood cells possess the Rh antigen are Rh+ (Approx 85%) Antibodies against Rh antigens are not
present at birth but are stimulated by exposure
Hemolytic Disease of the Newborn Only in Rh- mothers and an Rh+ child,
after exposure. RhoGam - medication given to
prevent sensitization of Rh- mother
Blood Disorders - Erythrocytes
Anemia – due to decreased number of red blood cells or a deficiency of hemoglobin
RBC deficiency aplastic anemia - destruction of bone marrow
hemorrhagic anemia - blood loss hemolytic anemia - rupture of RBC’s
Hemoglobin deficiency pernicious anemia - vitamin B12 deficiency
iron deficiency
Blood Disorders - Erythrocytes
Thalassemia - faulty hemoglobinFound in people of Mediterranean descent
Sickle-cell - faulty hemoglobinFound primarily in Africa and people of African descent.Provides resistance against Malaria
Polycythemia - excess RBC’s.
White blood cell disorders Leukopenia / leukocytosis Infectious mononucleosis
excess numbers of agranulocytes caused by Epstein-Barr virus
Leukemia predominate cell type acute (quick advancing chronic (slow advancing)