IC2 Flashcards
What does blood consist of?
Plasma, WBC, RBC
What is Pernicious anaemia caused by
Lack of vit B12/ intrinsic factor
Types of anemia
Nutritional, renal, aplastic, haemorrhage, malaria, sickle cell, erythroblastosis fetalis
Causes of polycythemia (excess RBC)
- Primary: tumour in bone marrow
- Secondary: erythropoietin-induced, adaptive mechanism to improve oxygen carrying capacity of blood e.g. in high altitude
- Other: dehydration
different types and causes of stroke
1) Haemorrhage (caused by blood vessel rupture in brain)
2) Ischemic stroke (caused by clot in cerebral blood vessel)
Is fibrinogen a protein?
Yes
Is platelet a complete cell?
No, it is a cell fragment
How to find haematocrit
RBC/ total blood volume
1 RBC transports around ____ O2 molecules
10^9
Is heme a protein?
No, it is a pigment
Each Hb molecule can transport _____ molecules of O2
four
Hb bound to CO2 is known as Deoxyhemoglobin (T/F)
False. It is known as carbaminohemoglobin
Place of erythropoiesis: < 5 y/o
All bone marrow
Place of erythropoiesis: 5 - 20 years
bone marrow in ribs, sternum, vertebrae, proximal ends of long bones.
Place of erythropoiesis: > 20y/o
bone marrow in ribs, sternum, vertebrae
Erythropoiesis is Controlled by____ which is produced in the _____.
Erythropoietin; kidney
Erythropoietin release and RBC production are regulated by _____.
tissue oxygenation
Erythropoietin release by the kidneys is triggered by?
- Low RBCs
- Low O2
- Incr tissue demand for O2
- Reduced blood flow to kidney
Erythropoietin is secreted by the kidneys only. (T/F)
False, it is 90% secreted by kidney & 10% by liver
Why do men have higher RBC count than women?
Androgen (found in men) enhances erythropoiesis
______count is indicative of erythropoiesis.
Reticulocyte (pre-RBC)
Destruction of RBC: what happens to iron?
Stored in liver, or reused in bone marrow
Destruction of RBC: what happens to globin?
Globin is metabolized into amino acids and is released into the circulation
What determines blood viscosity
RBC concentration
Corpuscular means ____
RBC
High red cell distribution width indicates ___
Anaemia (due to variation in sizes of RBC)
Leukocytosis mean high/ low WBC?
High; opposite of leukopenia (low WBC)
Difference btw leukemia and lymphoma
Both are cancers of WBC, but leukemia is located in blood while lymphoma is located in lymphatic system
Do platelets contain nucleus and ogranelles?
No nucleus, but have organelles
Which factor is the fibrin stabilising factor?
factor XIIIa (13a)
Role of factor XIIIa
Forms cross-links btw fibrin strands, thereby reinforcing fibrin mesh
Role of thrombin
- Activates factor XIII into XIIIa
- Converts fibrinogen into fibrin
What converts prothrombin into thrombin?
Factor Xa, with presence of Ca2+ and factor Va
Extrinsic pathway: What happens after tissue damage?
Damaged tissue releases tissue factor/ plasminogen which activates factor VII into factor VIIa
Intrinsic pathway: order of coagulation cascade (clotting factors)
Factor 12,11,9,10
Calcium is factor ___
IV
Thrombin is factor ___
IIa
Most clotting factors are derived from the ___
liver
______, a prostaglandin produced by intact endothelial cells, inhibits platelet activation and limits spread of blood clotting
Prostacyclin
How does fibrinolysis occur
Surrounding tissue and vascular endothelial cells release tissue plasminogen activator -> cleaves plasminogen (trapped in clot) to plasmin
Plasmin digests fibrin, dissolving the clot. Macrophages remove remains of clot.
What is haemophilia? Which gender is more prevalent?
Excessive bleeding after injury; Men as it is a X-linked condition
Which hemophilia (A-C) is the most prevalent, and what is it caused by?
A; deficiency in factor VIII (8)
Haemophilia B is caused by deficiency of factor ____
IX
Haemophilia C is caused by deficiency of factor ___
XI
Cause of Thrombocytopenia
damage / destruction of bone marrow
Treatment for thrombocytopenia
Treated with fresh whole blood transfusions or platelet transfusions.
PTT is known as ___
partial thromboplastin time
PTT is used to monitor ____therapy
heparin
PT (prothrombin time) is used to monitor ___ therapy
Warfarin
PTT measures efficacy of the _______
intrinsic and the common coagulation pathways
PT measures efficacy of the ______
extrinsic and common pathways
Factors included in PPT
Factor 1,2,5, 8-12
Factors included in PT
Factor 1,2,5, 7&10
INR formula
Ratio of patient PT to the PT of a healthy person