Question

Differentiate between the following pairs based on what is mentioned in the brackets :
Renal cortex and renal medulla {parts of nephrons present}

Answer 1

Hint:-The major function of kidneys is to rid the body of waste materials that are either ingested or produced by metabolism. It also controls the volume and electrolyte composition of body fluids.
Each kidney in the human contains about one million minute tubular structures called nephrons. Each nephron is capable of forming urine. A nephron is made up of- Bowman's capsule, glomerulus, proximal and distal convoluted tubules and loop of Henle.


Complete Answer:-The kidney contains majorly two parts which are named as- renal cortex and renal medulla. The renal cortex is the outer part of the kidney and the medulla is the inner part. Thus there are two types of nephrons found in the kidney named as - cortical nephrons and medullary nephrons.
In the renal cortex, the parts of nephrons found are- bowman capsule, glomerulus, PCT and DCT whereas in the renal medulla loop of Henle, collecting duct and duct of bellini are found. The major portion of the kidney is the cortical part so the nephrons present in it (cortical nephrons) constitute about three fourth portion of all the nephrons present in the kidney. Whereas medullary nephrons constitute about one-fourth of all the nephrons.
The Bowman's capsule and the glomerulus of the cortical nephrons are located close to the kidney surface whereas in the medullary nephrons these are located at the junction of cortex and medulla. The loop of Henle in cortical nephrons is mostly confined to the cortex, and a tiny part of it runs in the medulla whereas the loop of Henle in medullary nephrons is long, dipping deep down into the medulla.
Peritubular capillary networks are present in cortical nephrons but these are reduced in medullary nephrons. Also, vasa recta are highly reduced or absent in cortical nephrons but it is present in medullary nephrons.


Note:- The blood plasma is filtered by the glomerulus of the nephron into the Bowman's capsule. It then reaches a proximal convoluted tubule (PCT) where the reabsorption takes place. Then it goes to the loop of Henle where the concentration of urine occurs and then it reaches the distal convoluted tubule. From DCT it enters the collecting duct and then all the collecting ducts open into the bellini duct.
From here it enters into renal papilla, then to the renal calyx. From renal calyx, it enters into the renal pelvis and then it ureters. Finally, urine is released after storing in the bladder through the urethra.