1.3 blood clotting
TRANSCRIPT
7CHAPTER 11.3 Understanding the Mechanism
of Blood Clotting
13 January 2011
2:45 pm to 3:30
Learning Outcomes:
At the end of this class you must be able to
explain the necessity for blood clotting at the site of damage vessels
explain the mechanism of blood clotting
predict the consequences of impaired blood clotting in an individual
Necessity for Blood Clotting
Avoid excessive blood loss when a person is injured
Maintains the circulation of blood in a close circulatory system
Maintains blood pressure
Prevents the entry of foreign substances, such as microorganism into the body through the wound.
Blood Clotting Mechanism
A cut in a blood vessel
Platelets on exposure to air, break down and
release chemicals to cause other platelets to stick to each other
Blood flow out and vessel constricts
Platelets clump together to
form a plug to prevent blood
loss
Platelets release clotting
factor
Blood Clotting Mechanism
Injury in blood vessels
Platelet clump at the wound
Platelets releases Thrombokinase
ProthrombinThrombin
Fibrinogen Fibrin
Mesh network
In the present of factor VIII convert
Formed in the liver requires vitamin K and Ca
convert
Soluble plasma protein Insoluble fibres protein
Blood ClotScab
Consequences of Impaired Blood Clotting Mechanism
haemophilia
* Lack of gene for production of clotting factor (vitamin K)* An impaired clotting mechanism which causes serious bleeding
* Factor VII can now be produced by generic
engineering
ThrombosisEmbolism
* A local blood clot (thrombus} is formed on the damage rough inner wall of the artery. (thrombosis)* Blockage of the artery * Thrombus dislodge and is carried away by blood circulation (embolus)* Embolus trapped and block the blood flow
* Avoid to take foods rich in fats Consume more fruits and vegetables* Exercise and practice a healthy lifestyle
Heart attack
* The coronary artery is partially blocked , it cause angina (chest pain)* Total blockage : cuts off the supply of oxygen and nutrients to the heart muscle causes heart attack* Extensive heart muscle damage can cause death
CAUSES
OVERCOME
Terms in Blood Clotting•Fibrinogen, Factor I - A protein present in blood plasma; converts to fi brin when blood clots•Prothrombin, Factor II - A protein in blood plasma that is the inacti ve precursor of thrombin•Thromboplastin, Thrombokinase, Factor III - An enzyme liberated from blood platelets that converts prothrombin into thrombin as blood starts to clot•Calcium ion, Factor IV - Ion of calcium; a factor in the clotti ng of blood•Proaccelerin, Prothrombin accelerator, Accelerator factor, Factor V - A coagulation factor•Proconvertin, Cothromboplastin, Stable factor, Factor VII - A coagulation factor formed in the kidney under the infl uence of vitamin K•Antihemophilic factor, Antihaemophilic factor, Antihemophilic globulin, Antihaemophilic globulin,Factor VIII, Hemofi l - A coagulation factor (trade name Hemofi l) whose absence is associated with hemophilia A•Christmas factor, Factor IX - Coagulation factor whose absence is associated with hemophilia B•Prothrombinase, Factor X - Coagulation factor that is converted to an enzyme that converts prothrombin to thrombin in a reaction that depends on calcium ions and other coagulation factors•Plasma thromboplastin antecedent, Factor XI - Coagulation factor whose defi ciency results in a hemorrhagic tendency•Hageman factor, Factor XII - Coagulation factor whose defi ciency results in prolongation of clotti ng time of venous blood•Fibrinase, Factor XIII - In the clotti ng of blood thrombin catalyzes factor XIII into its acti ve form (fi brinase) which causes fi brin to form a stable clot
Activity 1 : 5 minutes conversationLet talk about blood clotting
Situation:
Hidayah’s finger bleeding because off paper cut. She is panic and worry. Darren tell Hidayah to calm down.
Darren : Don’t worry your blood will clot immediately.
Hidayah : clot? What do you mean my blood will clot?
Darren : ……….…………….
Hidayah : How it can be happened
Key words :Atika : thrombokinase, Raihan : Fibrin, Raihanah : vitamin K, Darren :,calcium
Exercise
Answer the following questions:
1. What is the function of thrombokinase?
____________________________________________
2. ____________soluble plasma protein converts into ____________insoluble fibrin fibres by the _____________
3. Prothrombin formed in the ____________ , it formation requires ______________ and _____________
4. What happen to the platelets when it expose to air.
____________________________________________________
5.Differentiate between thrombosis and embolism
____________________________________________________
6. Differentiate between angina and heart attack
__________________________________________________
homework
Draw mind map to summarize the necessity for blood clotting
Draw a diagram/flow chart to show mechanism of blood clotting
Draw a table to compare and contrast circulatory system of insect, fish, amphibians and humans