Tag: transport of molecules

Quizzes (0) Questions (64)

Questions Related to transport of molecules

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

If two solution have the same osmolarity, they are said to be

  1. Hypertonic

  2. Hypotonic

  3. Isotonic

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Isotonic means two solutions having the same osmolarity. It allows the free movement of water across the membrane without changing the solute concentration. Hypotonic surrounding solution means a solution with less osmolarity. This means that concentration of solutes is less in the surrounding medium, than the concentration of solutes in cell sap and hypertonic surrounding solution means the concentration of solutes is more than the concentration of solutes in the cell sap.

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

The space between the plasma membrane and the cell wall of a plasmolyzed cell surrounded by a hypertonic solution is occupied by the

  1. Hypotonic solution.

  2. Isotonic solution.

  3. Hypertonic solution.

  4. Water.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A plant cell wall is fully permeable and it cannot regulate the entry or exit of a solution. When a plant cell is placed in a hypertonic solution it will lose water by exosmosis. This process is called plasmolysis. The protoplasm will shrink and will move inwards and away from the cell wall. As a result, the hypertonic solution will occupy the space between the plasma membrane and the cell wall. Thus the correct answer is option C.

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

All the following involves osmosis except.

  1. Water from soil entering a root hair

  2. Water passing from root hair to adjacent cells

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

  4. Water entering a mesophyll cell from xylem vessel element
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Osmosis is the movement of water across a semi-permeable membrane. Water moving up a xylem vessel is primarily driven by transpiration pull and cohesion-tension, not osmosis.

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

Two cells A and B are contiguous. Cell A has osmotic pressure $10$atm, turgor pressure $1$ atm and diffusion pressure deficit $3$ atm. Cell B has osmotic pressure $8$ atm, turgor pressure $3$ atm and diffusion pressure deficit $5$ atm. The result will be?

  1. Movement of water from cell B to A

  2. No movement of water

  3. Equilibrium between the two

  4. Movement of water from cell A to B
Reveal answer Fill a bubble to check yourself
A Correct answer
Multiple choice biology movement in and out of the cell transport of molecules osmosis and plasmolysis plant water relation

When a plant cell is placed in a solution which is hypotonic to the cell sap, which of the following conditions will not apply

  1. The water potential of the cell sap will rise

  2. The suction pressure of the cell sap will fail

  3. The cell will become turgid

  4. The wall pressure of the cell will fail
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

If a cell is placed in hypotonic solution, water start moving into the cell by the process of endosmosis and cell become turgid.

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

All the following involve osmosis except.

  1. Movement of water from soil to root

  2. Movement of water from root hair to endodermis and pericycle

  3. Movement of water between xylem elements

  4. Movement of water form xylem to mesophyll cell of leaves
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Similar to the previous question, movement of water between xylem elements is bulk flow, not osmosis.

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

Consider the following events involved in stomatal opening:
1. Turgor pressure of guard cells increases
2. $K^+$ ions move into guard cells
3. pH of guard cells decreases
4. Water moves into guard cells
What is the correct sequence of these events leading to stomatal opening:

  1. 2-4-3-1

  2. 3-2-4-1

  3. 2-3-4-1

  4. 3-1-2-4
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The sequence is: K+ ions move into guard cells (2), which lowers the water potential, causing water to move in (4), which increases the turgor pressure (1). The pH change (3) is associated with the K+ transport.

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

Choose the correct answers from the alternatives given :
The osmotic pressure of pure water is

  1. 0

  2. 0.1

  3. 1

  4. 10
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Osmotic pressure is the minimum pressure applied to prevent the inward flow of solvent molecules from a dilute solution into the concentrated solution, where both solutions are separated by a semipermeable membrane. 

The osmotic pressure would be zero if pure water were on both sides of the semi-permeable membrane. 

So the correct answer is "0"