Renal Anatomy and Blood Supply
Start with the big picture
The kidneys lie behind the peritoneum between T12 and L3, with the right kidney slightly lower because of the liver. Each kidney has an outer cortex and an inner medulla, regions associated respectively with filtration and concentration. Blood enters through the renal artery and passes through segmental, interlobar, arcuate, and cortical radiate arteries before reaching glomeruli via afferent arterioles. Efferent arterioles then lead to peritubular capillaries in the cortex or vasa recta in the medulla. This two-stage capillary arrangement supports distinct processes across the kidney. The lesson also introduces juxtamedullary nephrons and the vasa recta’s role in the osmotic gradient involved in concentrating urine.
What you'll learn
- Locate the kidneys and describe their relationship to the peritoneum and liver.
- Distinguish the renal cortex and medulla by their roles in kidney function.
- Trace the main arterial branches supplying the kidney.
- Explain how afferent and efferent arterioles connect glomeruli with downstream capillary networks.
- Relate juxtamedullary nephrons and vasa recta to urine concentration.
Continue your study
Work through the complete notes and reinforce the topic with the study tools available in the full lesson.
