Projection of cortex into medulla is called

Answer

**Step-by-Step Solution:**

1. **Understanding Kidney Structure**: The kidney is divided into two main regions: the outer region known as the cortex and the inner region known as the medulla.

2. **Identifying Components**: The cortex contains structures such as the Malpighian body (which includes the glomerulus and Bowman's capsule) and the proximal convoluted tubule (PCT). The medulla contains the loops of Henle and is characterized by conical structures called medullary pyramids.

3. **Recognizing Projections**: The question specifically asks about the projections of the cortex that extend into the medulla.

4. **Naming the Projections**: These projections are known as the renal columns of Bertini. They are the extensions of the cortical tissue that separate the medullary pyramids within the medulla.

5. **Conclusion**: Therefore, the projection of the cortex into the medulla is called the renal columns of Bertini.

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