The digested food in small intestine is absorbed into blood vessels in the walls of small intestine through millions of tiny finger-like outgrowths called W. The undigested and unabsorbed food from the small intestine enters into another organ X. The organ X absorbs most of the water from the undigested waste food material making ir semi-solid. This semi-solid waste is stored in Part Y of organ X for some time. It is passed out from the body through part Z in the form of faeces.
What is W?

Answer

**Step-by-Step Solution:**

1. **Understanding the Function of the Small Intestine**: The small intestine is responsible for the digestion and absorption of nutrients from food. It has a specialized structure to facilitate this process.

2. **Identifying the Structures in the Small Intestine**: Within the walls of the small intestine, there are numerous tiny finger-like projections. These structures play a crucial role in increasing the surface area for absorption.

3. **Naming the Structures**: These tiny finger-like outgrowths are known as "villi". They are essential for the absorption of digested food into the blood vessels present in the walls of the small intestine.

4. **Conclusion**: Therefore, the answer to the question regarding what W is, is "villi".

**Final Answer**: W is "villi".

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