Ans.Structure of Kidney
Shape
Kidneys are dark-red, bean shaped organs.
Size:
Each kidney is 10 cm long, 5 cm wide and 4 cm thick and weighs about 27 grams.
Place of Attachment
They are placed against the back wall of abdominal cavity just below diaphragm, one on either side of vertebral column. They are protected by the last 2 ribs. The left kidney is a little higher than the right.
External Morphology
The concave side of kidney faces vertebral column. There is a depression, called hilus, near the centre of the concave area of kidney. This is the area of kidney through which ureter leaves kidney and other structures including blood vessels, lymphatic vessels and nerves enter and leave kidney.
Internal Morphology
The longitudinal section of the kidney shows two regions. Figure 11.3
Renal cortex, is the outer part of kidney and it is dark red in colour.
Renal medulla is the inner part of kidney and is pale red in colour.
Pyramids
Renal medulla consists of several cone shaped areas called renal pyramids.
Pelvis
Renal pyramids project into a funnel-shaped cavity called renal pelvis, which is the base of ureter.