Loop of henle, Biology

Loop of Henle

The reduced volume of fluid from the proximal tubule, still isosmotic to blood, enters the descending limb of Henle's loop. As the fluid passes down the descending limb, it enters re3ions where the tubular walls are surrounded by interstitial fluid of increasing osmotic and Na+ concentration. The walls of the descending limb are permeable to water and salts. So, water leaves and sodium enters the tubular fluid so that as it descends the loop of Henle, the fl lid becomes progressively more concentrated and hyperosmotic to blood. There is also perhaps some inward diffusion of urea from a urea-rich interstitial space. As a result of these events, the tubular fluid, at any given level in the descending limb, maintains isosmotic relationship to the surrounding interstitium.

The tubular fluid from the descending loop of Henle passes through the hair-pin bend of the loop, and enters the ascending limb of Henle's loop. The walls of ascending loop do not permit diffusion of water and salts. However, the cells of these walls, particularly of the deeper parts of the ascending limb, actively transport Na+ outward. Recent studies reveal that it is Cl- which is actively transported out of the ascending limb and Na+ accompanies as the counter-ion. In this part there may also be some active transport of urea out of the tubular fluid. Because of this active transport out of the tubule, the fluid becomes progressively more dilute as it moves up the ascending limb. Since ascending limb is impermeable to water, there is no entry of water into the tubular fluid from the surrounding interstitium. Due to the net withdrawal of solute, the fluid at any given level in the ascending limb is hypoosmotic to the fluid in the interstitium as well as the descending limb.

Posted Date: 1/16/2013 1:56:13 AM | Location : United States







Related Discussions:- Loop of henle, Assignment Help, Ask Question on Loop of henle, Get Answer, Expert's Help, Loop of henle Discussions

Write discussion on Loop of henle
Your posts are moderated
Related Questions
Q What are the few representatives of the phylum Mollusca? Octopuses, Snails, oysters and squids are examples of molluscs. Q. In which habitats do molluscs live? Mollus

Traumatology : This is the study of wounds. In other words we can say that traumatology  is the study of wounds or injuries which can be caused by accidents or violence to a person

Q. What are the structures that form the external ear? What is its function? The internal ear comprises the auricle or pinna and the auditory canal its function is to conduct t

Calculate Temperature for Survival and Growth of Microorganisms? Survival and growth of microorganisms is also affected by the temperature. According to their temperature requi

DIVERGENC E - In it blastomeres move in different directions i.e. inside the blastocoel the blastomeres move in different directions. The blastomeres which move inside i

Q. Qualitative and Quantitative Analysis of Colour? Primarily, two types of analysis are carried out for food colours - qualitative and quantitative. The qualitative analysi

CHECKER BOARD (PUNNET'S SQUARE) METHOD 1.         If the genotypes of the parents are known, the genotypes of their offspring can be easily predicted with the help of a chart c

Define Direct measurement of individual's Work Capacity? Direct measurement of VO 2 max is determined by having the subject perform exercise at increased loads, for 12 to 15 m

Describe about the Lysosomes enzymes Within the cytoplasm of the cell, several hydrolytic enzymes (lytic enzymes) capable of hydrolysing proteins, nucleic acids and carbohydra

The highest possible magnification that can obtain when using using a microscope?