Platelets and Blood Plasma

thrombocytes

Another name for platelets, which are small cell fragments in blood that play a crucial role in the clotting process.

thrombocytes average count

150,00 - 350,000 ul

Life span of thrombocytes

7-10 days

explain a platelet plug

A platelet plug is formed when platelets adhere to damaged blood vessel sites, aggregate together, and release chemical signals to facilitate further clotting and stabilize the injury.

Serotonin does what

Serotonin triggers vasoconstriction and promotes platelet aggregation in hemostasis.

Platelet derived growth factor

is a protein that regulates cell growth and division, particularly in healing and repairing blood vessels.

What is the origin of platelets

Myeloid stem cells form into megakaryoblasts that breakdown into platelets. Platelets are the fragments of megakaryoblasts

Fibrinogen

protein form of fibrin used for blood clotting

Hemostasis

the process to control bleeding

Starts with vascular spasms where serotonin is secreted. Platelet plug formation occurs making contact with exposed collagen fibers and finally coagulation occurs where fibrinogen converts into fibrin

Extrinsic clotting mechanism

The pathway in blood coagulation triggered by external trauma to a blood vessel, involving tissue factor and leading to thrombin generation.

Intrinsic clotting mechanism

The pathway in blood coagulation activated by damage to the blood vessel endothelium, involving factors within the blood itself and leading to thrombin production.

Hormonal pathway

Explain the common pathway

The pathway that both mechanisms use in the end.

Factor 1

Fibrinogen is activated into fibrin that binds together with other fibrin and exposed collagen fibers

Factor 2

Calcium binds to prothrombin and turns it into thrombin, thrombin will then convert fibrinogen into fibrin.

Explain prothrombin activation

Prothrombin activation is the process where prothrombin is converted into thrombin, facilitated by calcium ions and various clotting factors, which is essential for the formation of fibrin from fibrinogen.

Which mechanism is activated first

Extrinsic mechanism

Activated from damaged vessels/tissues

Initiated from tissue and thromboplastin that triggers the coagulation cascade.

Intrinsic mechanism

Triggers from blood contact with connective tissue

Initiated buy the Hageman factor

Hageman factor

Also known as Factor XII, it is a plasma protein that initiates the intrinsic pathway of coagulation upon contact with negatively charged surfaces, leading to the activation of other clotting factors.

Explain the conglutination cascade

The coagulation cascade is a complex series of enzymatic reactions that lead to the formation of a blood clot. It is divided into intrinsic and extrinsic pathways, ultimately resulting in the conversion of fibrinogen to fibrin, which stabilizes the clot.

Explain factor 3 activation

Factor 3, also known as Tissue factor, is a crucial protein that initiates the extrinsic pathway of coagulation when exposed to blood. It binds with Factor VII to form a complex that activates Factor X, leading to thrombin generation and clot formation.

Explain what happens to clots after they are used

Condenses into compact structures known as scabs. The clot will dissolve during a process called fibrinolysis, where enzymes like plasmin break down fibrin, restoring normal blood flow.

Fibrinolysis

is the process of breaking down fibrin in blood clots. It involves the enzyme plasmin, which digests fibrin and dissolves the clot after it has served its purpose.

Plasminogen

A precursor that is converted to plasmin, the enzyme responsible for breaking down fibrin in blood clots during fibrinolysis.