Answer:
Renal capsule.
Step-by-step explanation:
The renal capsule is known as a fibrous layer. That fibrous layer helps to cover the kidney in a layer of perirenal fat (known as the adipose capsule). The renal cortex is known as the outer part of the kidney where ultrafiltration occurs. It is present between the renal medulla and the renal capsule.
The renal capsule is important for the physiological function of the kidney in the human body. It helps to influence interstitial pressure and consistently tubular reabsorption of water and sodium.