Explain the kidney function in human biology, Biology

Assignment Help:

Explain the Kidney Function in human biology?

Blood first enters the capillaries in Bowman's capsule where it is filtered. The pores in the capillary walls allow water and small molecules to pass through, but are too small to allow red blood cells and large protein molecules to pass. The process by which material is filtered into Bowman's capsule is not very selective, and some of these substances that are of value to the body need to be reclaimed. Material filtered through the capillary walls into Bowman's capsule flows along the renal tubules. The process by which material is returned to the blood through the walls of the tubules is called tubular reabsorption.

Sodium, potassium, calcium, other minerals, and glucose are returned by active transport. These substances then enter the capillaries by diffusion. Water is returned by osmosis mostly in the proximal convoluted tubule, following the movement of glucose. There is additional reabsorption of salts and nutrients from the distal convoluted tubule, but this section of tubule also removes wastes and other substances not originally filtered out by Bowman's capsule through a process called tubular secretion. The pH of the blood is adjusted by the secretion of hydrogen ions into the filtrate. Potassium ions, ammonia, and certain drugs are eliminated by secretion from the distal convoluted tubules.

The loops of Henle function to concentrate the filtrate by establishing an osmotic gradient in the extracellular fluid around the loops that will later pull water from the collecting ducts. The ascending limb of the loop pumps NaCl out by active transport, but the ions cannot diffuse back in because this portion of the loop is impermeable to water. Salts can diffuse into the descending limb, but these are pumped out again when they reach the ascending loop, increasing the extracellular ionic concentration. When the filtrate reaches the collecting ducts, its osmotic concentration is much lower than the extracellular fluid of the medulla, so it loses water by osmosis and becomes more concentrated. As much as 99% of the water that goes through the tubules and collecting ducts is returned to the blood.

 


Related Discussions:- Explain the kidney function in human biology

Coelentrates, classification of coelenterats?

classification of coelenterats?

#title., poor metabolism phenotype will have

poor metabolism phenotype will have

What are the result of arterial switch operation, What are the result of Ar...

What are the result of Arterial Switch operation ? The operation is highly specialised. When carried out in experienced centers the mortality for simple TGA and TGA with VSD i

What is suturing technique, Normal 0 false false false ...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Steps for prevention industrial accidents, Steps for Prevention Industrial ...

Steps for Prevention Industrial Accidents These steps are as follow: Substitute a less hazardous equivalent. Remove worker from hazard (e.g. automate the sys

Why is aids difficult to prevent by vaccination, Why is AIDS difficult to p...

Why is AIDS difficult to prevent by vaccination? It is complex to produce a vaccine against AIDS because the HIV is a highly mutant virus. In almost every replication the produ

Fundamental structure of a virus, Q. What is the fundamental structure of a...

Q. What is the fundamental structure of a virus? Viruses are constituted of genetic material RNA or DNA covered by a protein capsule also known as a capsid. Some viruses, like

Fowl pox, F o wl pox Fowl pox is a contagious disease of birds, cause...

F o wl pox Fowl pox is a contagious disease of birds, caused by a member of family Poxviridae, characterized by wart-like nodules on the skin and diphtheritic necrotic membra

Explain the soft diet, Explain the soft diet The soft diet provides so...

Explain the soft diet The soft diet provides soft whole food that is lightly seasoned and moderately low in fibre. The foods have a soft  texture and are easy  to digest. Smal

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd