Exam 4: Chapter 16 Flashcards
what is plasma?
surrounds the cells of the connective tissue in the blood
-considered an extracellular matrix
-made up mainly of water
what are the four types of plasma cells?
albumins
globulins
fibrinogens
transferrin
what do albumins do?
MAJORITY
-colloid osmotic pressure
what do globulins do?
antibodies, protein carriers, and other clotting factors
what do fibrinogens do?
forms fibrin threads for forming a clot
what do transferrins do?
transports iron
-important for heme groups!
what are the three cellular elements?
RBC
white blood cells
platelets
what are the five types of white blood cells (leukocytes)?
lymphocyte
monocyte
neutrophil
basophil
eosinophil
what do lymphocytes do?
T & B cells
-specific immune responses
what do monocytes do?
differentiate into macrophages
-phagocytic
what do neutrophils do?
MAJORITY
-mobile phagocytes
-first to arrive at infection
what do basophils do?
contain granules of histamine
-allergic response
-less than 1%
what do eosinophils do?
parasitic infections
-allergic responses
what is a hematocrit?
tells us the % of RBCs
-low RBC = less resistance
-high RBC = more resistance
what are the two precursor cells for a RBC? whats the difference b/w them?
erythroblasts = nucleus
reticulocyte = no nucleus
does a mature RBC have a nucleus?
NO!!
-cannot replicate!
what is the shape of RBC’s? what three things about the morphology give us clues for disease?
biconcave disks (more flexibility)
-shape, color, size give us clues for disease
what is the main protein in RBCs?
hemoglobin
what is the structure of hemoglobin?
4 peptide chains (2 alpha, 2 beta)
-each chain has a heme group (porphyrin ring, iron molecule)
what does hemoglobin do?
carries O2
what does ferritin do?
stores iron in the liver
how are RBCs recycled in the liver?
heme -> billrubin -> bile
what is the shortest lived cellular element? longest lived?
shortest: white blood cells (hours)
longest: RBCs (4 months)
what is anemia?
decreases O2 carrying capacity in the blood
-can no longer carry normal amount
-fewer RBCs produced OR RBCs are lost at a faster rate
-due to iron, folic acid, or vitamin 12 deficiency
what are platelets?
does coagulation (clotting)
-very small (cell fragments)
-no nucleus
-live for 10 days
what is the precursor for platelets?
megakaryocytes
-platelets break off megakaryocytes in the bone marrow
what is hemostasis?
preventing blood loss from damaged vessels
what are the three steps to hemostasis?
- vasoconstriction (minor tears)
- platelet plug (mild tears)
- coagulation (severe tears)
how does vasoconstriction help prevent blood loss?
decreases blood flow to the area
-mediated by paracrines
what is the platelet plug pathway?
- exposed collagen
- attracts and activates platelets
- releases factors (platelet activating factor, van willibrand factor, thromboxane A2)
- positive feedback loop to attract and activate platelets
what does the platelet activating factor do?
attract and activate platelets
what does the van willibrand factor do?
adheres platelets to collagen
what does thromboxane A2 do?
attract and activate platelets
how do you stop the formation of the platelet plug?
prostacyclin and NO stop platelet adherence
what is the coagulation pathway?
INTRINSITC
1. exposed collagen
2. factor12
EXTRINSIC
1. damaged tissue around vessel
2. factor3
3. factor7
COMMON
1. factor10
2. prothrombin -> thrombin
3. fibrinogen -> fibrin
4. factor13
5. cross-linked fibrin clot
what two things is the coagulation pathway dependent on?
Ca2+ and Vitamin K
what is the process that removes the fibrin in the clot?
fibrinolysis
what is the process of fibrinolysis?
- plasminogen -> plasmin (TPA: tissue plasmin activator)
- breaks down fibrin
- clot dissolved
what do anticoagulants do? what are the two ways it acts?
prevents coagulation
-inhibition of platelet adhesion
-inhibition of coagulation cascade
what two things inhibit platelet adhesion?
prostacyclin
NO
what two things inhibit the coagulation cascade?
antithrombin 3
heparin
what is hemophilia?
uncontrollable loss of blood
-can’t make clots
what is the process of a pluripotent hematopoietic stem cell?
uncommitted stem cell (can become any blood cell)
↓
progenitor cell (committed cell, after hematopoiesis)
found in bone marrow!!
what is the process called that synthesizes blood cells?
hematopoiesis
where does hematopoiesis occur in an embryo?
liver and spleen
what is red marrow?
hematopoiesis occurs
-due to hemoglobin present
what is yellow marrow?
very little hematopoiesis occurs
-due to high levels of fat present
what is hematopoiesis controlled by?
cytokines
what is the cytokine called that controls red blood cell production?
erythropoietin (EPO)
what is the process of erythropoiesis?
- hypoxia (low O2)
- EPO released by kidney
- bone marrow
- RBC production
- increases hemoglobin
- increases O2
what cytokine controls platelet production?
thrombopoietin (TPO)
where are platelets produced?
liver
what two main things controls white blood cell production?
colony-stimulating factor
interleukins
what do interleukins do?
messengers from white BC to act on other white BC
-differentiation of white BCs
what do colony-stimulating factors do?
produces white BCs
-made with endothelial cells, fibroblasts, leukocytes
-able to determine differential white cell count (elevated=infection)
