Thrombocytes are responsible for

Step 1: Analyze the question The question asks about the function of thrombocytes. The key is knowing what thrombocytes are.

Step 2: Explain the concept Thrombocytes are another name for platelets. The word "thrombo-" relates to clotting (as in thrombosis, a blood clot). They are small, irregular cell fragments in the blood, produced in the bone marrow, and they have no nucleus.

Quick review of the blood components:

• Red blood cells (erythrocytes): carry oxygen, which is transported mainly by haemoglobin.
• White blood cells (leucocytes): fight infection. Phagocytes ingest bacteria and lymphocytes produce antibodies.
• Platelets (thrombocytes): help blood clot.
• Plasma: transports dissolved digested food, hormones, and waste products such as urea and carbon dioxide.

Step 3: Solve by checking the options

• A. Blood clotting: correct. When a blood vessel is injured, platelets gather at the site and release substances that help convert fibrinogen to fibrin. The fibrin forms a mesh that traps blood cells and seals the wound.
• B. Digestion of food: this is done by enzymes in the digestive system, not by blood cells.
• C. Ingestion of bacteria: this is done by phagocytic white blood cells, not platelets.
• D. Transportation of digested food: this is done by blood plasma.
• E. Transportation of dissolved oxygen: oxygen is carried by red blood cells.

Step 4: Answer Thrombocytes are responsible for blood clotting, so the answer is A.

Exam tip: Link the "thromb-" in thrombocytes to "thrombosis" (clot formation). Also remember that the prefix "erythro-" means red, so erythrocytes are the red cells that carry oxygen, and "leuco-" means white, so leucocytes are the white cells for defence.