Lecture 2: Cardiovascular System Flashcards
Does blood leave vessels?
no
What are the 3 parts of the cardio system?
- heart -> provides force to pump blood
- blood vessels -> house & trabsport blood
- blood -> carries & trabsports materials
What makes 55% of blood volume?
matrix/plasma
What are the 2 functions of blood vessels?
- prvent leakege of materials
- provide selectively permeable barrier
What are the formed elements in blood?
- RBCs -> 95%; erythrocytes responsible for gas transport
- cellular fragments -> platelets responsible for clotting
- WBCs -> .1%; leukocytes responsible ofr immune response
Where do all formed elements come from?
bone marrow
Where is embryonic hematopoiesis found?
- yolk sac
- liver
- spleen
- bone marrow
- spongy bone
- medullary cavity
Where are formed elements found in adults?
- spongy bone of axial skeleton
- long bones
- lymph nodes
- bone marrow
What 2 organs retain hematopoietic ability but are inactive?
liver & spleen
Where do lymphoid stem cells differentiate?
- T cells & NK cells -> in lymphatic tissue & thymus
- B cells -> in bone marrow
What do myeloid stem cells produce?
- progenitor cells to respond to chemicals
- megakaryocytes -> thrombocytes/platelets
- erythrocyte -> RBCs
- myeloblast -> WBCs (basophils, neutrophil, eosinophil)
Where do erythrocytes originate?
kidneys then bone marrow
What do eerythrocytes release that trigger RBC production?
erythropoietin
What is anemia?
deficiency in RBCs or hemoglobin
What is the composition of hemoglobin?
- 4 globin subunits with heme group
- each heme has an iron factor & binds one O2
- amino acid in globin bind CO2
Each RBC has how many hemoglobins?
300 million
Do people with type O blood have any antigens?
no
What are antigens?
cell surface proteins that form a personal signature
People who lack Rh antigens are Rh positive or negative?
negative
If someone lacks A, B, & Rh antigens what type blood are they? (vice/versa)
O- blood
What is agglutination?
antibodies bind to antigens on multiple cells
How are agglutinated cells destroyed?
by WBCs
What is the principle component of the immune response?
WBCs (eosinophils, basophils, lymphocytes, monocytes, neutrophils)
What triggers WBCs?
thymosins & cytokines
What is the most abundant WBC?
neutrophil
What are the characteristics of neutrophils?
- phagocytize bacteria & cellular debris
- secrete peroxide & lysozyme to kill invaders
- dead neutrophils form component of pus
What are the characteristics of basophils?
- trigger inflammation
- release histamines & heparin
- activate allergies
What are the characteristics of eosinophils?
- release proinflammatory cytokines
- recruit leukoctes
- weakly phagocytic but can aggregate & kill parasites
What are the characteristics of monocytes?
- largest cell
- phagocytize bacteria, parasites, & damaged cells
- become large macrophages when they leave blood
- removes damaged RBCs
What are the characteristics of lymphocytes?
- develop into T & B cells
- main acquired immune cell (learn identity of invader)
- matuee in bone marrow
- Ab production
What are the characteristics of platelets?
- fragment of megakaryocytes
- grow in response to thrombopoietin from liver & kidneys
- responsible for closing breaks in vessels
How do platelets close brekas in vessels?
- vasospasm -> contraction of smooth muscles to reduce blood loss
- clotting factors release by damaged tissue
- platelet plug closes vessels off
How do platelets trigger clotting?
release factors to trigger coagulation cascade
What is the coagulation cascade?
- prothrombin converts to thrombin
- fibrinogen converts to fibrin
- fibrin forms mesh web to catch blood cells & platelets forming a clot
How does warfarin work as a blood thinner?
reduces clotting production (prevents thrombus formation)
