Correct Option
The correct option is Columns of Bertini.
Explanation
The internal structure of the human kidney is divided into two main zones: an outer cortex and an inner medulla. The medulla is divided into several conical masses known as medullary pyramids, which project into the calyces. The arrangement of these tissues defines the gross anatomy of the kidney.
Option Analysis
- Columns of Bertini Columns of Bertini: Correct. The renal cortex extends in between the medullary pyramids as renal columns. These specific anatomical extensions are technically referred to as the Columns of Bertini (or renal columns). They contain blood vessels and urinary tubes and anchor the cortex.
- Pyramids of Malpighi Pyramids of Malpighi: Incorrect. This term is historically used to describe the medullary pyramids themselves or is sometimes confused with Malpighian corpuscles (which constitute the glomerulus and Bowman's capsule). It does not refer to the cortical tissue between the pyramids.
- Rathke’s columns Rathke’s columns: Incorrect. This is not a recognized anatomical term in renal physiology. Rathke’s pouch is an embryological structure related to the formation of the anterior pituitary gland (hypophysis), unrelated to the kidney.
- Aquaporin tracts Aquaporin tracts: Incorrect. Aquaporins are integral membrane proteins that serve as channels for the transfer of water across cell membranes. They are molecular structures, not macroscopic anatomical extensions of tissue.
Key Takeaway
Columns of Bertini are the extensions of the renal cortex that project into the inner aspect of the kidney, separating the medullary pyramids.