The kidney is one of the main organs of human bodies that carry out the entire process of ultrafiltration. The main and functional unit or part of the kidney is the nephron. These nephrons are divided into two parts. One is the cortical nephrons and the other one is juxtamedullary nephron.
Basically, cortical nephrons and juxtamedullary nephron are the two main types of nephrons that are present in the kidneys of the vertebrates. Both of these nephrons consist of the glomerulus, loop of Henle and above all a collecting duct. However, both of these nephrons have a good difference between each other. The difference lies in case of Loop of Henle.
In the cortical nephron the loop of Henle extends till the outer region of the renal medulla whereas in case of juxtamedullary the loop of Henle extends in the deeper part of the inner medulla. Usually a healthy person possess have 0.8 to 1 million nephrons in the kidney. Nephron goes deeper into the medulla.
Cortical vs Juxtamedullary Nephron
The difference between Cortical and Juxtamedullary Nephron is that in Cortical nephrons, the glomerulus is located near the outer parts of the cortex and they have short loops of Henle. In case of Juxtamedullary nephrons, the glomerulus is located near the cortex-medulla junction and they have long loops of Henle that pierce deep into the medulla.
Comparison Table Between Cortical and Juxtamedullary Nephron (in Tabular Form)
|Parameter of Comparison||Cortical Nephron||Juxtamedullary Nephron|
|Type of nephron||Penetratess deep into the nephron.||Goes deep into the medulla|
|Location||Found in the outer layer of the cortex||Found in the inner part of the cortex.|
|Size||Glomerulus is smaller in size.||Glomerulus is bigger in size.|
|Length of loop of Henle||Length is shorter in cortical nephron||Length is much bigger in this nephron|
|Percentage of nephrons||Human body possess 85% of cortical nephron||Human body possess 15% of this type pf nephron.|
What is Cortical Nephron?
It is a nephron that mainly contains a small part of the loop of Henle. It penetrates mainly in the outer part of the renal medulla. About 85% of the human kidney has cortical nephron. So, it can be assumed that the excretory and regulatory part of human body is mainly carried out by cortical nephron. Cortical nephrons have small glomerulus that is mainly found in the outer renal cortex.
The renal corpuscles have capillaries that are termed as the glomerulus. Both the cortical and juxtamedullary capsules are the functional units of kidneys. Both of them are entrusted with the proper functioning of the kidney.
What does glomerulus do? It receives the blood by afferent arteriole and the blood leaves mainly through the efferent arteriole. Blood filtration is the main function of the glomerulus. In the filtration process all amino acids, water, glucose, ions and small molecules of 40 kDa are filtered into the Bowman’s space. Only white blood cells or WBC, Red Blood Cells or RBC and proteins remains inside the glomerulus.
The main question arises is where does reabsorption take place? It takes place in the renal tubules of the cortical nephron. Almost all water, glucose and amino acids are absorbed in the renal tubulus. The reabsorption of the important molecules mainly takes place in the vasa recta. It is a vascular network of Loop of Henle. As the loop of Henle is short the vasa recta also appear small in the cortical nephrons. However, the final filtration in the nephron is termed as “urine”.
What is Juxtamedullary Nephron?
It connotes those nephrons that mainly extend to the renal medulla. The extension is deep and long. About 15% of nephrons present in the human kidney are juxtamedullary nephron. The renal corpuscle of the juxtamedullary nephron is mainly present in the renal medulla. They contain a good number of the glomerulus and this ultimately increases the rate of filtration. As the loop of Henle is long it extends to a long part.
Juxtamedullary nephrons are also present between the birds and mammals.
The main function or work of juxtamedullary nephron is to either concentrate or dilute the urine. It is also present within the animals. Animals that mainly live in terrestrial environments have many number of juxtamedullary nephrons in comparison with the cortical nephrons.
Nephrons also have some essential elements that are renal tubule, Bowman’s capsule, connecting tubule, distal convoluted tubule, Loop of Henle and other types of vital ones. All of them are equally responsible for the smooth functioning of the nephron. The intermediate nephron is another important type of nephron.
Main Differences Between Cortical and Juxtamedullary Nephron
- The cortical nephron is a type of those nephrons that never penetrates deep into the medulla and the glomerulus is found in the cortex. The juxtamedullary nephron is also a type of nephron that goes deep into the medulla and resides in the border of the cortex and medulla.
- The cortical nephron is mostly found in the outer layer or part of the cortex. Juxtamedullary nephron is found in the inner part of the cortex that is near to the medulla.
- The size of the glomerulus is smaller in size in case of cortical nephrons. The size of the glomerulus is much larger in case of juxtamedullary nephrons.
- The length of the loop of Henle is shorter in the cortical nephron. The length of the loop of Henle in Juxtamedullary is longer.
- The concentration of renin enzyme is higher in cortical nephron. Whereas Juxtamedullary nephron has no such concentration of rennin en.
- Human body possess about 85% of cortical nephrons. Juxtamedullary nephron occupies about 15% in the human body. It is much lesser than cortical nephrons.
Kidneys have both the type of nephrons. Nephrons are made of two things. One is the renal corpuscle and the other one is renal tubule. Both of them occupy a vital position in the human body. Cortical nephrons come with a good number of uses. It controls the excretory and regulatory systems of the body which is very vital. Juxtamedullary nephrons control and help in diluting the urine in the human body.
The main difference mainly lies in respect to the structure and functions of the nephrons. Both of them are vital without which it becomes for the humans to survive. Each one is related to the other one.
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