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The figure shown below represents a kidney nephron. Use it to answer the questions that follow.

The figure shown below represents a kidney nephron. Use it to answer the questions that follow.
BIOLOGY3212019436.png
(a) (i) X is made up of a tuft of capillaries. How do they differ from other capillaries in the body?
(ii) What structural difference exist between W and Z?
(iii) State the significance of the difference stated in (a) (ii) above.
(b) State three adaptations that enable P to perform its function.
(c) What is counter flow and in which part of the nephron does it occur.

Answers


sharon
(a) (i) They are more permeable to water than capillaries.
ii) Z has a wider lumen than N (acc converse)
iii) This increases high blood pressure within the glomerulus.
(b) - One cell thick to reduce distance for reabsorption.
- Cells have numerous mitochondria to produce energy for active transport ; have microvilli to increase surface area for
re-absorption ; Highly coiled to reduce spread of flow to increase time available for reabsorption.
(c) A condition where fluids flow in opposite directions / glomerular filtrate flow opposite direction to blood in capillaries;
parts T and Q.
sharon kalunda answered the question on March 21, 2019 at 13:41

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