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

Name of the terminal portion of the axon, Q. What is the name of the termin...

Q. What is the name of the terminal portion of the axon? The terminal portion of the axon is called as presynaptic membrane Through, this membrane neurotransmitters are release

Define the estimation of haemoglobin in blood, Define the Estimation of Hae...

Define the Estimation of Haemoglobin in Blood? Several methods are used to determine haemoglobin. In these methods hemoglobin is measured as oxyhaemoglobin, carboxyhaemoglobin,

Describe the nutritional and functional role of manganese, Minerals :- Mang...

Minerals :- Manganese Food Source      Whole grains, fruits, vegetables Nutritional Functional role Essential nutrient: Deficiency extremely rare. Enzyme cofactor

Explain ventricular fibrillation and pulseless ventricular, Explain Ventric...

Explain Ventricular Fibrillation (VF) and Pulseless Ventricular Tachycardia (VT) The commonest rhythm seen in cardiac arrest is VF, which may be preceded by a short period of

Which is the vertebrate class, Q. Which is the vertebrate class that is con...

Q. Which is the vertebrate class that is considered the first entirely terrestrial? Totally independent from the aquatic habitat, The first entirely terrrestrial vertebrate cla

Explain the eating disorder not otherwise specified (ednos), Explain the Ea...

Explain the Eating Disorder Not Otherwise Specified (EDNOS)? Earlier, we emphasized that a diagnostic category for eating disorders that fail to meet full criteria for anorexia

What is meningitis, Q. What is meningitis? The Meningitis is the generi...

Q. What is meningitis? The Meningitis is the generic name given to inflammation of the meninges and membranes that cover the central nervous system. The Meningitis can have sev

What is the significance of immunogenicity, Problem: Explain the proced...

Problem: Explain the procedure for import of cosmetics in US. - Briefly explain the procedure for import of cosmetics in US What are the major points to be considered whe

How do grasslands differ from savannas, How do grasslands differ from Savan...

How do grasslands differ from Savannas? Name the two main categories of plant forms that dominate the desert vegetation.

How delayed complementary feeding cause pem, How Delayed Complementary Feed...

How Delayed Complementary Feeding Cause PEM? The mothers from poorer socioeconomic groups where PEM is more prevalent, delayed introduction of complementary foods (foods in add

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