Biology · Excretory Products and Their Elimination · NEET
Columns of Bertini (renal columns) are the parts of the cortex that extend inward between the medullary pyramids of the kidney. In simple words: the outer cortex tissue "dips down" into the medulla, and these dipping columns are called Columns of Bertini. Memory hook: a "Bertini" is the cortex sending a finger down BETWEEN two pyramids.
In a kidney section, the cone-shaped medullary pyramids are separated by cortex tissue that extends inward. These inward cortical extensions between the pyramids are the Columns of Bertini (renal columns). Tissue type is cortex, even though the position is deep among the pyramids.
Your doubts, answered
Are Columns of Bertini made of cortex or medulla tissue?
They are CORTEX tissue. NCERT says the cortex extends in between the medullary pyramids as renal columns called Columns of Bertini. So even though they sit deep down among the medullary pyramids, the tissue itself is cortical, not medullary. This is the single most tested point.
What is the difference between renal columns (Columns of Bertini) and medullary pyramids?
Medullary pyramids are the conical masses of MEDULLA that project into the calyces. Columns of Bertini are the CORTEX tissue that fills the gaps BETWEEN these pyramids. Pyramids = medulla; columns = cortex sitting between the pyramids. They are two different tissues lying next to each other.
Do nephrons lie inside the Columns of Bertini?
No, this is a NEET distractor. Nephrons are the functional units, and their renal corpuscles lie in the cortex generally. Columns of Bertini are just cortical extensions between pyramids; NCERT never says nephrons are 'located in' the columns. In NEET 2024, 'Juxta medullary nephrons are located in the columns of Bertini' was a WRONG option.
Why do we even need Columns of Bertini?
They anchor and separate the medullary pyramids and carry blood vessels (interlobar arteries and veins) between the pyramids toward and away from the cortex. For NEET, the key exam point is simply their identity: cortex extending between the pyramids. Function detail is secondary.
Are Columns of Bertini in the NCERT syllabus?
Yes. They are named directly in Chapter 16 (Excretory Products and their Elimination), NCERT Class 11, in the section on kidney structure right after cortex, medulla and medullary pyramids. It is a one-line fact that NEET uses as a trap option.
⚠️ The NEET trap ✗ Columns of Bertini are made of medulla tissue because they lie deep among the medullary pyramids. ✓ Columns of Bertini are CORTEX tissue that extends inward between the medullary pyramids. Their location is deep, but the tissue type is cortical. 🧠 Location is medulla-side, but tissue is CORTEX. NEET tests the tissue, not the location.
Real NEET questions
NEET 2024
Choose the correct statement given below regarding juxta medullary nephron.
A · Renal corpuscle of juxta medullary nephron lies in the outer portion of the renal medulla.
B · Loop of Henle of juxta medullary nephron runs deep into medulla. ✓
C · Juxta medullary nephrons outnumber the cortical nephrons.
D · Juxta medullary nephrons are located in the columns of Bertini.
Solution: Option D is a trap that tests the Columns of Bertini. Columns of Bertini are cortical extensions between the medullary pyramids, NOT a place where nephrons are 'located', so D is wrong. Option B is correct: in juxta medullary nephrons the loop of Henle runs deep into the medulla. Option A is wrong (renal corpuscle lies in the cortex, not medulla) and option C is wrong (cortical nephrons are the majority).
Solved Excretory Products and Their Elimination NEET PYQs
Try the real previous-year questions from this chapter — each with the answer and a full solution.
