Tag: transport of molecules

Questions Related to transport of molecules

Transporting pull arise mainly from

biology movement in and out of the cell transport of molecules osmosis and plasmolysis plant water relation

  1. Roots

  2. Leaves

  3. Stems

  4. All

Show answer
Correct Option: B
Explanation:

As water is lost from the surface of the leaves due to transpiration a strong suction force is transmitted through the active mesophyll cells to the ends of the water column in the root. This is called transpiration pull. It caused the entire water column to be pulled upwards. When the rate of transpiration is very high and the rate of absorption is slow the water in the xylem elements of the leaf develops a state of tension.

So, the correct answer is B.

Which of the following does not operate in the carrier concept of active absorption of minerals?

biology movement in and out of the cell transport of molecules osmosis and plasmolysis plant water relation

  1. Electron transport

  2. Contractile protein

  3. Protein lecithin

  4. Ascending water stream

Show answer
Correct Option: D
Explanation:
Plants absorb minerals from the soil in the form of inorganic ions. The process of mineral absorption and water absorption are separate processes occur in plants. Water absorption takes place actively by root pressure whereas mineral absorption takes place actively with the help of carrier proteins.
So the correct answer is 'Ascending water stream'.

Mineral absorption is mostly

biology movement in and out of the cell transport of molecules osmosis and plasmolysis plant water relation

  1. Physical process

  2. Chemical process

  3. Active process

  4. Passive process

Show answer
Correct Option: C
Explanation:
Mineral absorption takes place in two phases: active absorption and passive absorption. It mostly occurs using active absorption phase because it is a fast process of mineral absorption, utilise energy and unidirectional. It is a biochemical process that occurs against the concentration gradient with the help of carriers and pumps.
So the correct answer is 'Active process'.

Which one is not connected with transport across the cell membrane?

biology movement in and out of the cell transport of molecules osmosis and plasmolysis plant water relation

  1. Osmosis

  2. Active transport

  3. Diffusion

  4. Surface tension

Show answer
Correct Option: D
Explanation:

(A) Osmosis is the movement of the solute molecule from lower concentration to higher concentration through a semi-permeable membrane.

(B) Active transport is the transport of molecules which is energy dependent.
(C) Diffusion is the movement of molecules from a higher concentration to lower concentration.
(D) Surface Tension is the elastic tendency of a fluid surface to cover the least possible surface area.
So, the correct answer is 'Surface Tension'.