Kidney -

1. 2 in number. Dark red. Slightly flattened. Bean shaped.
2. 10 cm. long, 5 cm wide and 4 cm thick (In rabbit 20-25 mm). Weighing 150 gm in male 135 gm in female.
3. Mesodermal in origin. Retroperitoneal, i.e. peritonium present on ventral side. Metanephric.
4. Asymetrical, left kidney is 25 mm downward. Haemostatic organ given by w. cannon.
5. Attached to dorsal wall by mesorchium membrane.
6. Situated in anterior abdominal cavity, below diaphragm on both side of vertebral column between the last thoracic vertebrae & 2rd lumler vertebrae. Kidney are outerly convex and internally too.
7. Internally a notch hilum or hilus present, from this point renal artery enter, renal vein & ureter come out.
8. Diameter of renal artery is more than other normal artery. Kidney is covered by a capsule.
9. Outside capsule a fat layer of adipose capsule, followed by a fibrous membrane, i.e. renal fescia present.
10. It is solid, made up of 10,00,000 nephrons or uriniferous tubules.
11. In kidney outer part is cortex and inner part is medulla.

Cortex -

1. It is granular due to presence of Malpighian's capsule.
2. In between medullary rays of ferrin present. these are straight part of PCT and DCT.
3. Cortex enters into medulla region between 2 pyramides, in the form of column of bertini.
4. On their inenr side adipase tissue present.

Medulla -

1. Inner part made up of 15-16 pyramids. (In rabbit, mapsupials, insectivorus rodents, pyramid i.e. unilobular)
2. Central pointed part of pyramid is papillae. On papillae duct of bellini opens.
3. Papillae open in calyces. Calyces open in the pelvis.
4. From renal pelvis ureter is originated.