Blood Clotting

Which 2 substances are released by platelets?

• Serotonin

• Thrombin

• Fibrin

• Thromboplastin

What is the role of serotonin?

• triggers blood clotting cascade

• forms a mesh in the blood clot

• causes smooth muscles in blood vessels to contract

• signals to the brain that tissues are damaged

Thromboplastin is an enzyme that triggers the blood clotting cascade

• True

• False

Which reaction is catalysed by thromboplastin?

• conversion of prothrombin to thrombin

• conversion of prothrombin to fibrin

• conversion of thrombin to prothrombin

• conversion of fibrinogen to fibrin

Which ions must be present for thromboplastin to work?

• Na⁺

• Cl^-

• Ca²⁺

• H⁺

Thrombin is an enzyme that converts fibrin to fibrinogen

• True

• False

What is the role of fibrin in blood clotting?

• acts as an enzyme

• forms a mesh of fibres to cover the wound

• causes smooth muscles in blood vessels to contract

• starts off the whole process

Which of these proteins are SOLUBLE? (Tick all that apply)

• fibrin

• fibrinogen

• thrombin

• prothrombin