Loop of Henle

Question 1

What is the function of the loop of Henle?

Answer 1

section of the kidney tubule that enables mammals to produce urine more conc than their own blood

Question 2

How is the loop of Henle a countercurrent multiplier?

Answer 2

• different areas have different permabilities
• uses energy ot produce conc gradient that result in the movement of substances from one area to another
• cells use ATP to transport ions using active transport
• this produces a diffusion gradient in the blood

Question 3

What do the changes that take place in the decending limb of the loop of Henle depend on?

Answer 3

high conc of sodium and chlride ions in the tissue fluid of the medulla that are tehresults of events in the ascending limb

Question 4

What happens in the descending limb?

Answer 4

• leads from proximal convoluted tube
• water moves out of the filtrate down a conc gradient
• the upper part is impermable to water but the lower part is permable to water and runs down into the medulla

Question 5

How does the conc of ions change in the tissue fluid in the medulla?

Answer 5

• conc of sodium and chloride ions in the tissue fluid of the medulla gets higher and higher moving through form the corex to the pyramids
• as a results of the activity of the ascending limb

Question 6

How does the conc of the filtrate change as it moves through the descending the limb?

Answer 6

• entering it is isotonic with the blood
• water passes oiut of the loop into the tissue fluid by osmosis down a conc gradient
• then moves down a conc gradient into the blood of the surrounding capillaries
• resulting filtrate in the loop is hypertonic to the blood

Question 7

What is the descending limb not permable to?

Answer 7

• sodium and chloride ions
• no AT takes place in the descending limb

Question 8

What is the ascending limb permable?

Answer 8

• first section of the limb
  
  • very permable to sodium and chloride ions
  • they move out of the conc solution by diffusuion down a conc gradient
• in the second section
  
  • sodoum and chloride ions are actively pumped out into the medulla tissue fluid against a conc gradient

Question 9

Why does this occur in the ascending limb?

Answer 9

• high conc of ions in the medulla tissue
• impermable to water, so water cannot follow the ions down a conc gradient
• the fluid left in the ascending limb becomes increasingly dilute
• tissue fluid of the medulla develops a very high conc of ions - essential for the kidney to produce urine that is more conc than the blood
• key part of the countercurrent multiplier system

Question 10

What hapens as the fluid reaches teh top of the ascending limb?

Answer 10

it is hyptonic ot the blood again

Question 11

explain how longer loop of henle assists with preventing exessive water loss

Answer 11

• more sodium ions and chloride ion removed
• builds up greater water potential gradient
• removes more water from collecting duct

Question 12

explain role of loop of henle in the production of urine?

Answer 12

• causes a decrease in water in the medulla
• ascending limb active transport of ions
• walls of decending limb permeable to water
• water removed from decending limb
• water potential of tissues surroudning the collecting duct is lower than fluid inside it
• water remove from filtrate

Question 13

How is the loop of henle similar to something in fish

Answer 13

countercurrent multiplier