Capsule 

The renal capsule is the membranous covering of the kidney. It directly covers the renal cortex, which forms the outer stratum 

Each part of the capsule links to its explanation.

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Cortex 

The cortex of the kidney is the outer section which covers the internal medulla. The cortex is visible near the outer edge of the cross-sectioned kidney. It is composedof blood vessels and urine tubes and is supported by a fibrous matrix.

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Calyx 

The calyces (plural for calyx) are the recesses in the internal medulla of the kidney which enclose the pyramids. They are used to subdivide the sections of the kidney anatomically, with distinction being made between major calyces and minor calyces.

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Renal Column 

The renal columns are lines of the kidney matrix which support the cortex of the kidney. They are composed of lines of blood vessels and urinary tubes and a fibrous, cortical material.

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Pyramid

The renal pyramids are conical segments within the internal medulla of the kidney. The pyramids contain the secreting apparatus and tubules and are also known as the malphighian pyramids.

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Renal Sinus 

The renal sinus is the cavity within the kidney which houses the renal pyramid. Nerves and blood vessels pass into the renal sinus through the hilus.

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Hilus 

The hilus is the slit-like opening in the middle of the concave medial border of the kidney. Nerves and blood vessels pass through the hilus into the renal sinus within.

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Renal Artery  

One quarter of the total blood output from the heart comes to the kidneys along the renal artery. Two renal arteries arise from the abdominal section of the aorta, each artery supplies a lobe of the kidney. The incoming artery divides into four or five branches, eventually forming arterioles, each of which leads to the compact ball of capillaries called the glomerulus.

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Renal Vein 

Cell waste is discharged in the veins for excretion through the kidneys. The body circulates about 425 gallons of blood through the kidneys on a daily basis, but only about a thousandth of this is converted in urine. The remainder goes back into circulation through the renal arteries. From the Bowman's capsule, the blood is carried through the compact network of capillaries that forms the glomerulus within the capsule. The capillaries eventually reconverge into small venules which lead to the larger renal veins. There are two renal veins, one extending from each lobe of the kidney, and opening into the vena cava.