Tag: transport in plants

Questions Related to transport in plants

Choose the correct answers from the alternatives given :
Water potential is affected by

water potential water potential and pressure plant water relation transport in plants biology

  1. osmotic potential

  2. matric potential

  3. pressure potential

  4. all of these

Show answer
Correct Option: D
Explanation:
  • Water potential is the potential energy of water relative to pure water in a plant cell or tissue. This can be written as the sum of matrix potential (due to binding of water to cell and cytoplasm), the solute potential (due to concentration of dissolved solutes which by its effect on the entropy components reduces the water potential) and pressure potential (due to hydrostatic pressure, which by its effect on energy components increases the water potential).
  • Ψw = Ψs + Ψp + Ψm
  • So the correct answer is "All of these".
During photocatalytic splitting of water, liberation of $O _{2}$ requires 
water potential water potential and pressure plant water relation transport in plants biology

  1. $Mn^{2+} $

  2. $CI^{-} $

  3. $Ca^{2+}$

  4. all of these.

Show answer
Correct Option: D
Explanation:

The liberation of $ O _{2}$ during photolysis of water involves the role of $ Mn^{2+},Ca^{2+}$ and $CI ^{-}$ ions.

Water from soil enters into root hairs owing to

water potential water potential and pressure plant water relation transport in plants biology

  1. Atmospheric pressure

  2. Capillarity

  3. Root pressure

  4. Osmotic pressure or diffusion

  5. Turgor pressure

Show answer
Correct Option: D
Explanation:

Osmotic pressure of the cell sap of root hairs is usually higher than the osmotic pressure of the soil water. Therefore, the diffusion pressure deficit (DPD) and the suction pressure in the root hairs become higher and water form the cell wall enters into then through the plasma membrane by osmotic diffusion.

In simple osmotic system, at-constant temperatures, the water potential results from the combined but opposite actions of _______________.

water potential water potential and pressure plant water relation transport in plants biology

  1. Relative humidity and pressure potential

  2. Pressure potential and saturation vapour potential

  3. Saturation vapour pressure and osmotic potential

  4. Osmotic potential and pressure potential

Show answer
Correct Option: A

As the glomerular filtrate courses the tubules, its composition and osmotic concentration changes, due to tubular reabsorption. Which of the following is incorrect match regarding the segment of nephron and osmotic concentration of filtrate?

water potential water potential and pressure plant water relation transport in plants biology

  1. Segment of nephron -Proximal convoluted tubule Osmotic concentration of filtrate- Isotonic to blood plasma

  2. Segment of nephron -Descending limb of Henle's loop Osmotic concentration of filtrate- Hypertonic

  3. Segment of nephron -Ascending limb of Henle's loop Osmotic concentration of filtrate- Hypotonic

  4. Segment of nephron -Bowman's capsule Osmotic concentration of filtrate- Hypotonic

Show answer
Correct Option: A

Which of the following statements is correct?

water potential water potential and pressure plant water relation transport in plants biology

  1. Bacteria do not survive in salted pickles because they get plasmolysed in hypertonic medium

  2. Osmotic potential is numerically equal to the osmotic pressure but is negative in sign

  3. Kneading of wheat flour is accompanied by release of heat which is due to imbibition

  4. All of these

Show answer
Correct Option: D
Explanation:

Following are the correct statements:

(1) Bacteria do not survive in salted pickles because they get plasmolysed in hypertonic medium.
(2) Osmotic potential is numerically equal to the osmotic pressure but is negative in sign.
(3) Kneading of wheat flour is accompanied by the release of heat which is due to imbibition.
So, the correct answer is (d).

Choose the correct answers from the alternatives given :
In which one of the following processes the phenomenon of osmosis is not involved

water potential water potential and pressure plant water relation transport in plants biology

  1. Water entering a mesophyll cell from xylem vessel element

  2. Water passing from root hair to adjacent cells

  3. Water from soil entering a root hair

  4. Water passing up a xylem vessel element to xylem vessel above it

Show answer
Correct Option: D
Explanation:

Osmosis is the movement of solvent from its higher concentration to its lower concentration across a semipermeable membrane. Movement of water through xylem element to xylem vessels above it occurs due to the cohesive force between the water molecules, suction pressure and transpiration pull.


So the correct answer is "Water passing up a xylem vessels element to xylem vessel above it".

Supply ends in transport of solute are

biology transport in plants diffusion transport in vascular plants types of transport

  1. Green leaves and storage organs

  2. Root and stem

  3. Xylem and phloem

  4. Hormones and enzymes

Show answer
Correct Option: A
Explanation:

Source and sink are important concepts in translocation in plants. In plants, organic solutes are translocated from regions of their synthesis like green leaves or storage organs like tubers in stem and roots to the region of their active utilisation like the regions of active growth at tips of stem and roots. Thus green leaves and storage organs act as source, whereas regions of active growth act as sink for organic solutes.

Proton pump in thylakoid membrane is :

biology transport in plants diffusion transport in vascular plants types of transport

  1. PC

  2. Pheophytin

  3. Fd

  4. PQ

Show answer
Correct Option: A

Which region of plants is considered as supply end?

biology transport in plants diffusion transport in vascular plants types of transport

  1. Root

  2. Fruit

  3. Leaf

  4. Flower

Show answer
Correct Option: C
Explanation:

The translocation of sugars in a plant occurs from source to sink by active loading at source or supply end and active unloading at the sink end. The source and sink are not fixed and keep on changing depending on the physiology of plant. In water transport water is always transported from roots to the aerial parts but not so in case of sugars. 

Sugars are transported from a region, where they are present in high concentration, example leaves to regions of sugar utilisation or storage parts, example storage roots or tubers or fruits etc. 
Thus, storage organs like tubers, roots, fruits etc. serve as sink end and leaves acts as supply end.