Blood - Lecture 10 Flashcards
Hematocrit
Percentage of blood volume composed of erythrocytes.
If blood was centrifuged, what would each layer be composed of and what percentage would each layer be?
Red Blood Cells (45%)
Buffy Coat - White Blood Cells and Platelets (<1%)
Plasma (55%)
List the formed elements of blood.
RBCs/WBCs/Platelets
Normal blood pH
7.35-7.45
List the plasma proteins from most to least numerous.
Albumins (58%), globulins (37%), and fibrinogens (4%).
Name what each plasma protein plays a role in.
Albumins - transport proteins
Globulins - immune elements and antibodies
Fibrinogens - clotting cascade
What is colloid osmotic pressure?
Plasma proteins draw water into the blood.
Where does formation of blood cells occur?
Red Bone Marrow
Which organ regulates erythropoiesis?
Kidneys
Lifespan of erythrocytes
120 days
Define anemia
Decreased ability to transport oxygen
Define polycythemia
High red blood cell count that leads to increased viscosity of the blood that makes it harder to pump.
List the granulocytes (-phils) from most to least numerous
Neutrophils, Eosinophils, and Basophils
Neutrophils
Attack and destroy bacteria cells by engulfing them (60% of WBCs)
Eosinophils
Destroy parasitic worms
Dampen allergic reactions
(2-4% of WBCs)
Basophils
Release histamine (increases inflammation)
Release heparin which inhibits blood clotting
(<1% of WBCs)
List the agranulocytes
Lymphocytes and Monocytes
Lymphocytes
T - cells attack infected cells
B - cells release antibodies
(25% of WBCs)
Monocytes
Exit blood into tissue and become macrophages (large phagocytes)
(4-8% of WBCS)
Stages of Hemostasis
Vasospasm (immediate constriction of blood vessels to reduce flow), Platelet Plug Formation (30s to 1m after injury: platelets activated by exposure to collagen in tunica externa -> adhere to it and each other to form the plug), Coagulation (3-6 mins: fibrin in blood forms mesh that traps escaping erythrocytes)
Thrombus
Inappropriate clot in undamaged vessel.
Embolus
A thrombus that travels elsewhere in the body.
