Learn Vein Islets Termination Number definition and determination procedure. A vein termination is the free end of the vein islet.
Vein Islets Termination Number
Definition: Vein islet termination number is defined as the number of vein islet termination per sq.mm of the leaf surface, midway between midrib of the leaf and its margin.
How to determine?
Here is full procedure for determination of Vein Islets Termination Number.
Procedure:
- Take the fully grown leaf of the plant under study.
- Make suitable size pieces from the central parts between midrib and the margin.
- Dechlorophyllized the pieces of the leaf by boiling in choral hydrate solution for about thirty minutes.
- Arrange camera lucida and drawing board for making drawings to scale.
- Place a stage micrometer on the microscope.
- Use 10x objectives and 5x eyepiece.
- Draw a line equivalent to 1 mm as seen through the microscope and draw a square on this line.
- Adjust the black paper on board so that the square is seen in the eyepiece, in the center of the field.
- Place the slide with the cleared leaf (epidermis on the stage).
- Trace all the veins termination which seen as superimposed on the 1 sq. mm square.
- Count the number of vein islets in the square millimeter.
- Find the average number of vein islets termination from the four determinations, to get the average values for one sq.mm.
SAQ with Answer
- What is the purpose of this experiment?
The purpose is to quantify and assess the density of vein endings within a specific area of a leaf, which can provide valuable information about the leaf vascular structure and function.
- Why is it necessary to dechlorophyllize the leaf pieces before conducting this experiment?
Dechlorophyllization is necessary to make the leaf transparent and allow for better visualization of the vein terminations under the microscope. It removes the green pigments (chlorophyll) that can obstruct the view of the veins.
- What are the equipment using to conduct the determination of Vein Islets Termination Number?
The equipment tools include a fully grown leaf, chloral hydrate solution, camera lucida, drawing board, microscope with 10x objectives and 5x eyepiece, a stage micrometer, black paper and a slide for mounting the cleared leaf.
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