Chapter 18 - Blood Flashcards
Hematocrit
Take blood Centrifuge Separate out plasma, RBC and WBC
Distribution functions of blood
Deliver oxygen, hormones, and nutrients Remove waste CO2 to lungs Waste to Kidneys
Regulation Functions of Blood
Homeostatic regulation Adequate fluid volume Buffer for body pH
Protection Functions
WBC, external bacteria, mutated DNA, virus infected body cells, prevent blood loss, prevent infection
What is Plasma Made of
10% Proteins (60% Albumins) 90% Water, globulins, fibrinogen, electrolytes
Formed Elements
WBC - whole cell RBC - no organelles or nuclei Platelets Bone Marrow
RBC
erythrocytes - biconcave discs, anucleate, no organells, filled with hemoglobin (Hb), protein spectrin for flexiblity
Hemoglobin
Globin composed of 4 polypeptide chains Heme bonded to each globin (red) each Hb can transport 4 O2
Oxyhemoglobin
Loaded O2 (ruby Red)
Deoxyhemoglobin
Empty O2 (Dark Red)
Carbaminohemoglobin
Loaded CO2
Hematopoiesis
Blood Cell Production
Hematopoietic Stem Cells
Hemocytoblasts (All Formed Elements) Cells from red marrow enter blood sinusoids
Steps of Erythropoiesis
Myeloid Stem Cell Proerythroblast (commited RBC) Basophillic Erythroblast (ribosome synthesis) Polychromatic Erythroblast (Hb accumulation) Orthochromatic Erythroblast (Hb accumulation) Reticulocyte (ejection of nucleus) Enter blood stream and become mature RBC
Erythropoietin (EPO)
Stimulates RBC Production hormone from kidney
Hypoxia
Decreased RBC numbers due to hemorrhage or increased destruction Insufficient hemoglobin per RBC Reduced availability of O2
Recycled RBC parts
Iron salvaged for reuse Heme degraded to bilirubin which is secreted into intestines Globin metabolized into amino acids
Leukocytes
1% of total blood volume Defense against disease
Diapedesis
Leukocytes leaving capillaries
Types of Leukocytes
Granulocytes 1) Neutrophils 4) Eosinophils 5) Basophils Agranulocytes 2) Lymphocytes 3) Monocytes
Neutrophil
- Most numerous WBCs
- Granules stain lilac; contain defensins
- 3-6 lobes in nucleus; twice size of RBCs
- Very phagocytic
Basophil
- Rarest WBCs
- Nucleus deep purple with 1-2 constrictions
- Large, purplish-black granules contain histamine
- Similar to mast cells
Eosinophil
- Red-staining granules
- Bilobed nucleus
- Granules lysosome-like
- Role in allergies and asthma
- Role in modulating immune response
Lymphocyte
- Second most numerous WBC
- Large, dark-purple, circular nuclei with thin rim of blue cytoplasm
- Mostly in lymphoid tissue
- Crucial to immunity
Monocyte
- Largest leukocytes
- Abundant pale-blue cytoplasm
- Dark purple-staining, U- or kidney-shaped nuclei
- Actively phagocytic cells
Leukopenia
Abnormally low WBC Count
Leukemias
Cancer, many abnormal WBC
Myeloid Leukemia
Lymphocytic Leukemia
Acute Leukemia = stem cells (kids)
Chronic Leukemia = older ppl
Mononucleosis
contagious viral disease
Epstein-Barr virus
high # of atypical agranulocytes
Platelets
Fragments of Megakaryocytes
granules containing serotonin, Ca2+, enzymes, ADP, platelet-derived growth factor (act in clotting)
Formation regulated by thrombopoietin
Steps of Hemostasis
- Smooth muscle contracts causing vasoconstriction
- Platelet plug formation, platelets adhere to collagen fibers
- platelets release chemicals that make nearby platelets sticky
- Coagulation - fibrin forms a mesh that traps red blood cells and platelets forming a clot
Thrombus
Clot in Unbroken blood vessel
Embolus
clot in bloodstream
Embolism
Clot obstructing a vessel
Anticoagulant Drugs
Asprin
Heparin
Warfarin
Dabigatran
Thrombocytopenia
Deficient number of circulating platelets
Petechiae
appear due to hemorrhage due to destruction of red bone marrow, treated with transfusion of platelets
