Question
Second stage of urine formation is called selective re-absorption. Why?

Answer

The second stage of urine formation, tubular re-absorption, is called selective re-absorption The filtrate enters the kidney in the proximal tubule. This region of the kidney is special because many things can be removed from the filtrate. These valuable things are recollected, or reabsorbed, by the body.
Glucose, certain salts, vitamins, hormones, and amino acids are restored to the body and will not be included in urine. Sometimes, if the body has too much of something then the extra sugar or salt will stay in the filtrate. For example, diabetics with high levels of blood glucose may have glucose in their urine since it cannot all be reabsorbed. The filtrate after reabsorption is like pre-urine.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

How would you distinguish between baking powder and washing soda by heating?
Draw the electron-dot structures of the following compounds and state the type of bonding in each case:
i. KCl
ii. $NH _3$
iii. CaO
iv. $N _2$
v. $CaCl _2$​​​​​​​
a. Non-metal A which is the largest constituent of air combines with hydrogen on heating in the presence of Fe (as catalyst) and forms a gas.
b. When this gas B is treated with $H _2 SO _4$, compound C is formed which is broadly used as chemical fertiliser.
i. Identify A, B and C.
ii. Locate the position of $A$ in the modern periodic table.
iii. Which elements are present before and after the element $A$ ?
iv. Write the electronic configuration of element A .
Describe the exchange of gases which takes place in the leaves of a plant:
  1. During daytime.
  2. At night.
The pancreas is made up of two parts A and B. The part A secretes insulin whereas part B secretes pancreatic juice.
  1. Which part is functioning as an endocrine gland? Why?
  2. What is insulin and what effect does it have in the body?
  3. Name the disease which can be treated by giving insulin injection.
  4. What does pancreatic juice contain? Where does pancreatic juice go?
  5. Name the life process in which pancreatic juice is made use of.
An object is placed 10cm from a lens of focal length 5cm. Draw the ray diagrams to show the formation of image if the lens is:
  1. Converging, and
  2. Diverging.
Give one example each of a chemical reaction characterised by:
  1. Evolution of a gas.
  2. Change in colour.
  3. Formation of a precipitate.
  4. Change in temperature.
  5. Change in state.
Energy from various sources is considered to have been derived from the sun. Do you agree? Justify your answer.
The white solid compound A decomposes quite rapidly on heating in the presence of a black substance X to form a solid compound B and a gas C. When an aqueous solution of compound B is reacted with silver nitrate solution, then a white precipitate of silver chloride is obtained along with potassium nitrate solution. Gas C does not burn itself but helps burn other things.
  1. What is compound A?
  2. What is compound B?
  3. What is gas C?
  4. What do you think is the black substance X? What is its function?
  5. What is the general name of substances like X?
  1. What is scattering of light? Explain how the colour of the scattered light depends on the size of the scattering particles.
  2. Explain the reddish appearance of the Sun at sunrise or sunset. Why does it not appear red at noon?