Blood Flashcards
What is viscosity?
The resistance to flow (thickness of blood)
What are the functions of blood?
Transport heat, oxygen, CO2, hormones, water
Protects with coagulation factors and WBCs
What is the haematocrit?
The percentage of whole blood made up of RBCs
What is the composition of blood?
55% plasma, 45% cells
What is the function of albumin?
Influences blood pressure, flow and fluid balance
Hat is the structure of haemoglobin?
4 protein chains, 2 alpha 2 beta
1 molecule capable of carrying 4 oxygen molecules
What are the different types of granulocytes?
Neutrophils, eosinophils, basophils
What are the different types of agranulocutes?
Lymphocytes, monocytes
How do neutrophils act?
Phagocytosis of foreign bodies, increase during times of infection
How do monocytes act?
Move into tissues when mature and phagocytise any foreign bodies
What stimulates RBC production?
Erythroprotein
Describe haemopoiesis
Stem cells give rise to all blood cells. RBC starts with a nucleus but it fades as they mature. Cell size reduces and haemoglobin production begins
What is a reticulocyte?
A young RBC. Rare in blood circulation, appear only after severe blood loss
How are RBCs recycled?
Old RBCs are engulfed by monocytes in spleen and broken into haem and globin. Globin is broken into amino acids and name broken into iron and bilirubin
What is primary haemostasis?
Temporary plug of platelets
What is secondary haemostasis?
Coagulation, stable clot
What are the 3 main stages of coagulation?
Vascular spasm, platelet plug formation, coagulation
What is vascular spasm?
The constriction of a blood vessel triggered by pain receptors
What happens to form a platelet plug?
Platelets stick to exposed collagen of injured smooth muscle, plate,eats continue to stick together and release ADP to signal for more platelets
What happens in coagulation to form a clot?
Reaction cascade of clotting factors forms a clot. Fibrinogen is converted to insoluble fibrin by thrombin.
What are the different coagulation pathways?
Extrinsic and intrinsic
What happens in the extrinsic coagulation pathway?
Factors are released by tissues to begin coagulation, within 5 seconds of injury
What happens on the intrinsic coagulation pathway?
Factors in the blood form clot, occurs between 3-6 minutes
What blood type is the universal donor?
O
