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

Explain the occurrence of vitamin C, Explain the Occurrence of Vitamin C ...

Explain the Occurrence of Vitamin C Vitamin C (ascorbic acid) is an active ingredient present in any animal or vegetable cell which occurs in the plant in free form and also bo

Electrophoresis gel to load 60, Assume your tilapia fish muscle homogenate ...

Assume your tilapia fish muscle homogenate has a protein concentration of 5769 ?g/ml. You take 32.5 ?l of this fish homogenate, mix it with 12.5 ?l sample buffer and 5 ?l reducing

Explain adverse effects, Explain Adverse Effects Fluconazole is genera...

Explain Adverse Effects Fluconazole is generally well tolerated. Gastrointestinal distress and rash can happen. Stevens-Johnson syndrome, anaphylaxis and hepatic necrosis have

What are the stages of mitosis, Q. What are the stages of mitosis? Mito...

Q. What are the stages of mitosis? Mitosis involves replication of DNA and its separation into two new daughter cells. Whereas only four phases of mitosis are often listed. Ent

Explain right atrial enlargement, Q. Explain Right Atrial Enlargement ? ...

Q. Explain Right Atrial Enlargement ? The right atrium (RA) is a globular chamber, forming the right heart border on the PA view. On the PA view, the border of the enlarged RA

What chemical is used to test for the presence of co2, What chemical is no...

What chemical is normally used to test for the presence of carbon dioxide? What is the result of the test if carbon dioxide is present?   a) Lime water is used t

Primary tissues, what do primary tissues of a plant do

what do primary tissues of a plant do

Define hepatic triglyceride synthesis, Q. Define Hepatic Triglyceride Synth...

Q. Define Hepatic Triglyceride Synthesis? Fatty acid flux to the liver from adipose tissue appears to be an important determinant of hepatic triglyceride synthesis and VLDL sec

Explain cardiac examination auscultation and its techniques, Explain cardia...

Explain cardiac examination auscultation and its techniques? Auscultation of the heart sound and associatcd sound is very important to diagnose the cardiovascular diseases. It

Explain about the cardiovascular and circulatory system, Explain about the ...

Explain about the Cardiovascular and Circulatory System? Aging affects the cardiac muscle causing a diminished resting cardiac output. The capacity of myocardium for cellula

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