Question

10 You did an I Activity: Write in your own words activity in your 9th class by taking a Rheo leaf and breaking it into two parts and Woite your Observation and process in your own then peeling know a it List out the values ol words. B​

Answer 1

Answer:

Let us perform a simple experiment to study in detail about the process of plasmolysis in the plant cell.

Aim

To study the phenomena of plasmolysis in epidermal peels of Rhoeo plant leaves in hypotonic and hypertonic solutions using salt solution.

Theory

What is Plasmolysis?

It is a process of contraction or shrinkage of the protoplasm of a plant cell due to loss of water from the cell. It takes place in extreme conditions and hence occurs rarely. Plasmolysis can be carried out in a laboratory by submerging a living cell in a concentrated sugar or salt solution for water loss from the cell.

Why are Rheo plant’s leaves are used in this experiment?

The Rheo plant’s leaves are used in this experiment because the Rheo leaf has coloured cell sap, which can be examined clearly under a compound microscope.

How does water permeate through the cell membrane?

The cell membrane serves as a semipermeable membrane dividing the inner of all cells from that of its surroundings. This membrane permits movement of a few of the particles including, water molecules, ions across the membrane while blocking others. There is the continuous movement of water molecules in and out of the cell across the cell membrane ad also it serves as an important attribute for enabling cells to absorb water.

Materials Required

Needle.

Forceps.

Droppers.

Glass slides.

Watch glass.

Rhoeo leaf.

Cover slips.

Compound microscope.

Sodium chloride 5% solution.

Sodium chloride 0.1% solution.

Procedure

Take two clean and dried glass slides and place them on a table.

Select the fresh and cleaned Rhoeo leaf and place them on the watch glass.

Fold the leaves in such a way that it tears from the lower side of the leaf. Or, with the help of a clean blade.

Extract two small fragments of a fine and transparent layer with the help of forceps from the lower surface of the epidermis of the Rhoeo leaf.

Now set up the epidermal peels on each of the glass slides.

With the help of a dropper, add 1 to 2 drops of sodium chloride 0.1% solution on one of the prepared slide.

With the help of another dropper, add 1-2 drops sodium chloride 5% solution on the other prepared slide.

Now carefully set a cover slip on the peel of both sides with the help of a needle. Make sure, no bubbles are present.

Leave the prepared glass slide undisturbed for a few minutes.

Now carefully place the slides under a compound microscope and observe the changes.

Observation

After a period of 30 minutes, we can notice that cells placed in the sodium chloride 0.1% solution seem to be turgid and the cells placed in the sodium chloride 5% solution seem to be shrunk with the loss of water and it exhibits the process of plasmolysis.

Conclusion

Plasmolysis is observed when the plant cells are immersed in the concentrated salt solution or sodium chloride 5%  solution. During this process, 4 to 5 per cent of water passes through the cell membrane into the encircling medium. This occurs as the concentration of water inside the cell is higher than the outside of the cell hence the protoplasm induces shrinkage and takes a spherical shape.

When the plant cells are immersed in a dilute salt solution or sodium chloride 0.1% solution, the water in the plant cells moves from the outside to the inside of the cell as the water concentration is higher outside the cell as compared to the inside of the cell which causes the turgidity of the cell.

 

Precautions

The part of the rhoeo leaf that needs to be extracted for the experiment is the epidermal peel from the lower surface

Care needs to be taken to ensure that the peel is moist and not dry.

Answer 2

Answer:

RHOEO LEAF EXPERIMENT

Explanation:

AIM:

To observe GUARD CELLS and EPIDERMAL CELLS in a Rheo leaf.

APPARATUS REQUIRED:

• Rheo leaf
• Watch glass
• Weight
• Dropper
• Blade
• Safranin
• Coverslip
• Slide

PROCEDURE:

First of all, utilizing the weight crush the leaf from the center in order to break its upper lamina.

Now utilizing a blade cut a tiny portion of the oppressed tissue

Put some water in the watch glass.

Put that cut a transparent piece of leaf into this watch glass using forceps.

Put two drops of safranin into this watch glass to stain the specimen.

Now put the specimen carefully on the slide.

Put the coverslip onto it.

Put the set slide in the microscope and concentrate it to observe the specimen.

OBSERVATION:

• We will observe the red guard cells on the leaf
• We will also notice red-colored epidermal cells.

#SPJ3