Question

Natural anticoagulant is:
A. Serotonin
B. Digitonin
C. Heparin
D. Erythromycin.

Answer 1

Hint: Anticoagulants are the chemicals or substances that delay or stop the clotting of blood. They are also known as blood thinners. There is a mechanism for clotting of blood, to stop bleeding when there is a cut or wound or internal bursting of blood vessels. But in some cases, blockages occur and to release them, the body produces anticoagulants.

Complete Answer:
Serotonin is a neurotransmitter produced in the brain which regulates mood and happiness. It is the hormone associated with sleep, hunger and activeness.
Digitonin is a steroid obtained from the plant digitalis purpurea. It is used in making detergents and as a molecular extracting tool in biochemistry applications.
Erythromycin is basically an antibiotic that kills bacteria. It is used to treat many bacterial infections such as skin infections etc.
To maintain the organism to be alive, when there is bleeding, due to cuts or wounds, there is a mechanism of blood clotting to prevent bleeding. Substances or chemical molecules that participate in clotting of blood are called clotting factors. The substances or chemicals which function completely opposite to clotting factors are called Anticoagulants. They work by inhibiting or interfering with the clotting factors.
Anticoagulants are required to stop unwanted clotting within the blood vessels, such as in heart disease and blood related disorders. In mosquitoes and other insects which require blood for survival they are naturally occurring in abundant amounts to keep the area of bite not clotted.
Mast cells and basophils in our body produce an anticoagulant called Heparin. It activates a protein that inhibits the clotting mechanism and stops clotting.

Hence the correct answer is : C) Heparin.

Note:
Even plants produce some anticoagulants useful for humans and animals. They are called coumarins and are modified based on the function. In the lab to prevent clotting, certain chemicals like citrates and oxalates are used. They must be used with caution in treating blood disorders as they may have adverse side effects.