Question

Leech obtains continuous blood stream from its victim by pouring in it
1. Heparin
2. Hirudin
3. Insulin
4. Pepsin

Answer 1

Correct Answer - Option 2 : Hirudin

Explanation

• Leeches belong to the phylum Annelida. They are coelomate and triploblastic organisms. 
• They exhibit organ system-level organization. Their body is segmented.
• Hirudin is an anticoagulant present in the salivary glands of blood-sucking leeches. Due to its anticoagulatory property, the blood does not get clotted.
• Hirudin directly blocks the blood-clotting protein thrombin.
• This helps the leeches to feed on blood as hirudin ensures continuous flow of blood after the worm's initial puncture in the host's skin.

• Heparin is the most powerful anticoagulant. It activates the Antithrombin III present in the blood plasma
• The antithrombin binds and deactivates the serum clotting factors, this prevents the clotting of blood.
• The proenzyme pepsinogen on exposure to hydrochloric acid gets converted into the active enzyme pepsin.
• The enzyme pepsin is responsible for the digestion of proteins. Pepsin converts proteins into proteoses and peptones (peptides).
• Insulin is secreted by the β cells of islets of Langerhans. It is released into the bloodstream to lower down blood sugar levels and prevent hyperglycemia.