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

What do you mean by osteichthyes and condrichthyes, Q. From which features ...

Q. From which features do osteichthyes and condrichthyes get these names? "Chondros" means cartilage, "ictis" means fish (both from the Greek) the name chondrichtians is for fi

Discuss in detail about the mitochondria, Discuss in detail about the Mitoc...

Discuss in detail about the Mitochondria An important function of the cell is to derive energy from the different oxidisable nutrients, such as, carbohydrates and fats supplied

Zygote - embryogenesis, Zygote - Embryogenesis The fertilized egg or z...

Zygote - Embryogenesis The fertilized egg or zygote is situated at the micropylar end/pole of the embryo sac, its basal (micropylar) end is attached to the embryo sac wall and

What are their respective modes of transmission, What are some human diseas...

What are some human diseases caused by bacteria and what are their respective modes of transmission? The major human bacterial infections transmitted by respiratory secretions

How do the climate affect the growth of population, Q. How do the availabil...

Q. How do the availability of water and light and the climate affect the growth of a population? The availability of light and water and the climate are abiotic factors that li

How to get a stock primer concentration of 100µm, I have 30µg of a primer, ...

I have 30µg of a primer, whose molecular weight is 600. How much water should I add to get a stock primer concentration of 100µM?

What is the parasite that causes toxoplasmosis, What is the parasite that c...

What is the parasite that causes toxoplasmosis? How is the disease transmitted and what are its typical manifestations? Toxoplasmosis is caused by the protozoan Toxoplasma gond

Define total body potassium (tbk), Define Total Body Potassium (TBK)? ...

Define Total Body Potassium (TBK)? Potassium in the body is an index of body's total cell mass. A gamma counter measures the amount of a type of potassium which is assumed t

Show photosynthesis process in algae and plants, Q. Which all are the livin...

Q. Which all are the living beings that carry out photosynthesis? Which is the cell organelle responsible for the absorption of light for the photosynthesis process in algae and pl

What is punnett squares in genetics, What is Punnett Squares in genetics? ...

What is Punnett Squares in genetics? The probability, or likelihood, that a certain phenotypic or genotypic trait will appear in offspring can be predicted and diagrammed using

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