49. SAGITAL SECTION OF KIDNEY

A sagittal section of the kidney reveals a bean-shaped organ with a distinct, tough outer fibrous capsule and two primary inner regions: an outer lighter-colored cortex and an inner darker-colored medulla. The medulla contains cone-shaped renal pyramids, which drain into minor calyces, then major calyces, leading to the renal pelvis. 

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Key Anatomical Features (Sagittal Plane):

• Outer Capsule: A fibrous, protective layer surrounding the kidney.
• Renal Cortex: The outermost granular-looking layer containing nephrons.
• Renal Medulla: Inner region containing 8–18 cone-shaped renal pyramids.
• Renal Columns (of Bertin): Cortical tissue that extends down between the pyramids.
• Renal Sinus/Pelvis: The central collecting region that drains into the ureter, containing calyces, fat, and vessels.

• Hilum: The medial concave border where the renal artery, vein, and ureter enter/exit. 

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Internal Structures Observed:

• Renal Pyramids: Striated, triangular structures in the medulla.
• Minor & Major Calyces: Cup-shaped structures collecting urine from the pyramids.
• Renal Pelvis: A large, funnel-shaped chamber that collects urine from the calyces.
• Cortical Rays: Striations extending from the medulla into the cortex