Blood

Question 1

composition of blood

Answer 1

• 55% plasma
  
  • water, proteins, other solutes
• <1% platelets and WBC
• 45% RBC

Question 2

ratio of blood cells

Answer 2

• 4 million RBCs
• 350,000 platelets
• 5,000 WBCs

Question 3

cellular componenets of RBCs

Answer 3

• NO NUCLEUS
• biconcavity
  
  • for gas diffusion and squeeding through capillaries
• thin membrane for easy gas transport
• 120 day life cycle

Question 4

cellular components of WBCs

Answer 4

• nucleated
• classified as either granulocyte or agranulocyte

Question 5

granulocyte

Answer 5

WBC with secretory granules in the cytoplasm

Question 6

agranulocytes

Answer 6

no secretory granules

monocytes and lymphocytes

Question 7

Process of hematopoiesis to RBC

Answer 7

1. myeloid stem cell is made from pluripotent stem cell
2. If stimulated by GM-CSF, it can become a granulocyte or a monocyte.
3. BFU_E (Erythroid burst forming units) gives rise to CFU_E (Colony forming units- erythromycin)
4. CFU_E requires EPO to become RBC

Question 8

Process of hematopoesis to platelets

Answer 8

1. Pluripotent cells become myeloid cells
2. myeloid cells are affected by TPO (thrombopoetin) to become plateltes

Question 9

G-CSF

Answer 9

stimulates the bone marrow to produce granulocyts and stem cells and release them into the bloodstream

• stimulates the proliferation, differentiation, and maturation until it becomes a mature neutrophil

Question 10

How is hematopoiesis regulated?

multilineage

Answer 10

• SCF (Stem cell factor)- Supports colony growth, cells can become myeloid or leukocyte
• GM-CSF- Cells can become granulocyte or monocyte
• IL-6 - lymphoid arm ??
  
  • stimulates immune respone

Question 11

How is hematopoiesis regulated?

lineage-specific cytokines

Answer 11

• G-CSF - will make cell a granulocyte
• M-CSF - will make cell a monocyte
• Erythropoetin- makes cell into RBC
• Thrombopoietin- makes cell into platelet

Question 12

Erythropoiesis sequence

nucleus?

Answer 12

1. uncommitted pluripotential stem cell with nucleus
2. EPO makes it committed proerythroblast
3. becomes normoblast- nucleus shrinks and is reabsorbed
4. becomes reticulocyte and leaves the marrow ti enter blood stream NO NUCLEUS
5. becomes erythrocyte, cell achieves final shape and hemoglobin synthesis. Has no nucleus.

Question 13

___ Hb : ___ nucleus

Answer 13

more hb : less nucleus

Question 14

What is hemoglobin?

Answer 14

• made up of 2 alpha and 2 beta polypeptide chains (globulins) and Heme.
• heme is derived from iron
• Oxy hemoglobin- has O2 bound
• deoxyhemoglobin- does not have O2 bound

Question 15

What is required for hemoglobin synthesis?

Answer 15

• requirements:
  
  • proteins- amino acids for structure
  • vitamins- B12, B6, B2, E, C, and folic acid
  • Minerals- iron and copper

Question 16

What happens if you take B12 and/or folic acid out of the system?

Answer 16

Will do a bad job making DNA for hemoglobin and hemoglobin will be crappy and wierd shaped.

wont work as well

break down faster

Question 17

What happens to Iron?

Answer 17

• Fe is transported to liver by transferrin.
• it is stored in ferritin in the liver
• When you need it, the transferrin brings it back from storage site to the bone marrow to be used.
• Fe is inserted into the erythroblast and the mitochondria inserts it into the hemoglobin
• After the erythrocyte has been around about 120 days, macrophages in the spleen break it down.
• most of the Fe is recycled and stored in the ferritin again.

Question 18

What happens to the erythrocyte at the end of it’s 120 day life?

Answer 18

1. aged RBCs are destroyed by macrophages in the liver and spleen.
2. the globin (alpha and beta chains) break down into heme and porphyrin
3. Porhyrin becomes bilirubin and is transpoted to the liver where it is conjugated and secreted in the bile and goes to the intestines
4. **increased hgb breakdown or decreased liver/kidney function would cause jaundice

Question 19

Which protein makes somebody RH+?

Answer 19

the big D

Question 20

how long do thrombocytes circulate for?

Answer 20

about 1 week

Question 21

How are platelets made?

Answer 21

• megakaryocyte grows really big and little pieces break off
• little pieces break off, this process is called endomitosis and the pieces are the platelets.
• platelets have and ER, mitochondria, but no nucleus

Question 22

What makes up a platelet?

Answer 22

• alpha granules
  
  • contain clotting factors
  • When the alpha granule is activated to release, it releases:
    
    • pro von willebronds factor
    • factor V…etc.
• dense granules
  
  • have ADP, Ca, serotonin

Question 23

How does biopsy compare to aspiration when evaluating bone marrow?

Answer 23

• biopsy is more specific/reliable than aspiration
• biopsy is more expensive and painful
• biopsy gives more accurate measurement of iron.
• biopsy shows gross structure and abnormal cells better
• **must have at low numbers of at least two different types of cells to warrant a biopsy

Question 24

mean corpuscular volume

Answer 24

size/weight of RBCs in circulating volume.

weight of RBCs is made up of hgb so this gives you a way to estimate hgb

Question 25

How to peds RBC counts compare to adults and elderly

Answer 25

* higher blood cell counts as infants because hypoxic intrauterine environment stimulates epo * elderly blood cells have same lifespan but are replaced more slowly * lymphocye function decreases with age.

Question 26

How do platelets adhere

Answer 26

* VWF will adhere to collagen and start piling up * GP1b on the platelet will attach to the VWF * or GP1a will attach straight to the collagen * These attaching will activate GP2b and GP3a to begin aggregating

Question 27

primary hemostasis

Answer 27

1. exposure to collagen 2. platelets adhere 3. plateltes activated 4. aggregation 5. formation of platelet plug

Question 28

What does thromboxane do?

Answer 28

* with ADP it activates other plateltes and causes aggregation. * **Thromboxane** is released after GP2b and GP3a are activated.

Question 29

Secondary hemostasis i

Answer 29

1. **intrinsic system** activated by factor 12 2. Factor 12 activates factor 10 3. factor 10 activated prothrombin into thrombin 4. thrombin activates fibrinogen into fibrin 5. fibrin builds into clot, working best with normal Ca++ levels. \*\***Extrinsic system** is activated by _tissue factors_ and activates factor 10

Question 30

extrinsic system

Answer 30

The extrinsic pathway is activated by external trauma that causes blood to escape from the vascular system. This pathway is quicker than the intrinsic pathway.

Question 31

Intrinsic system

Answer 31

The intrinsic pathway is activated by trauma inside the vascular system, and is activated by platelets, exposed endothelium, chemicals, or collagen. This pathway is slower than the extrinsic pathway, but more important

Question 32

Factor X

Answer 32

Prothrombin activator. Cleaves prothrombin into thrombin (active) \*thrombin is an enzyme that breaks fibrinogen into fibrin

Question 33

how does the endothelium regulate clot formation?

Answer 33

* Endothelial cell makes prostacyclin * prostacyclin activates cAMP, decreasing Ca * prostacyclin inhibits Thromboxane * Need Ca to form clots

Question 34

What significance do the endothelial cells have?

Answer 34

* Endothelial cells activate protein C which inhibits clotting * When subendothelial tissues are exposed, clotting cascade starts * collagen * basement membrane * von willebrand factors

Question 35

Tertiary hemostasis

Answer 35

* the breaking down of the clots * T-PA is released from endothelial cells and converts plasminogen into plasmin * plasmin breaks down and degrades fibrinogen and fibrin * D-dimer results from breakdown of the clots * **PAI-1** and **antiplasmin** are inhibitors

Question 36

factor 1

Answer 36

fibrinogen

Question 37

factor 2

Answer 37

prothrombin

Question 38

factor 3

Answer 38

tissue factor