Pembuatan Sediaan Mikrotom (Praktikum Anatomi dan Identifikasi Kayu)-Pengamatan Mikroskopis Kayu

Summary

This practical session focuses on the preparation of microtome slides for anatomical research, specifically in wood anatomy. It outlines the detailed steps involved, from preparing wood samples to using a microtome for thin slicing. The process includes softening wood, staining with safranin, dehydration with alcohol solutions, and embedding the samples in xylene for preservation. The session concludes with microscopic examination, capturing images of the prepared slides at various magnifications to study wood’s cellular structure. The tutorial emphasizes precision and thoroughness in each step to ensure high-quality, permanent specimens for scientific analysis.

Takeaways

• 😀 The practice session focuses on preparing microtome specimens for anatomical research by cutting thin slices of wood for microscopic examination.
• 😀 A microtome is a scientific instrument used to slice samples into thin sections (about 10-12 microns thick) for detailed microscopic study.
• 😀 The necessary materials for this practice include ethanol, gloves, masks, a water bath, microtome knives, cover glasses, pipettes, and sample bottles.
• 😀 Before cutting, wood samples are prepared by choosing specific surfaces (radial, tangential, or cross-sectional) and measuring dimensions (e.g., 1x1 cm or 1x4 cm).
• 😀 The samples are labeled with wire tags to prevent confusion, especially after they are softened by boiling.
• 😀 Samples are softened by placing them in a water bath at 100°C for several days to weeks, depending on the type of wood.
• 😀 The softness of the wood is checked by attempting to cut it with a sharp cutter; if it adheres to the cutter, it is soft enough for sectioning.
• 😀 After softening, the wood is placed in the microtome, and thin slices are cut using a back-and-forth motion of the microtome knife.
• 😀 The thin slices are stained using safranin to highlight the cell walls and left for at least eight hours to ensure proper staining.
• 😀 The stained slices are then dehydrated using progressively stronger alcohol solutions (10%, 30%, 50%, 70%, 80%, 95%, and absolute alcohol) to remove water content from the sample.
• 😀 After dehydration, the slices are immersed in a preservative (such as a type of oil or preservative solution) to finalize the preparation and prevent degradation.
• 😀 The final microtome slides are placed on glass slides in the proper sequence (cross-sectional, radial, and tangential) and sealed with a cover glass using adhesive.

Q & A

What is the purpose of creating microtome slides in this practical session?

The purpose is to prepare thin slices of wood samples for microscopic examination of their anatomical structure. These slides help in detailed research on wood at a cellular level.

What is a microtome and why is it important in this process?

A microtome is a scientific instrument used to cut extremely thin slices (typically 10-12 microns) of materials like wood. It is essential for creating consistent, thin slices necessary for microscopic analysis.

What is the significance of the 1 cm x 1 cm size used for cutting the wood samples?

The 1 cm x 1 cm size is used to standardize the samples for cutting. It ensures that each wood sample is manageable and allows for accurate and consistent slicing, whether for tangential, radial, or cross-sectional planes.

Why are the wood samples labeled after cutting?

The samples are labeled to prevent mix-ups during the preparation process. This is crucial as the wood samples could lose their markings during softening or staining, which could lead to confusion.

How does the water bath contribute to the preparation of the wood samples?

The water bath softens the wood samples by heating them at 100°C. This step is necessary to make the wood pliable enough for precise slicing with the microtome, and the softening process can take up to a week, depending on the wood type.

What happens if the wood sample is not sufficiently softened?

If the wood sample is not soft enough, the slices will be thick and uneven, making it difficult to observe fine anatomical details under the microscope. Testing with a cutter helps ensure that the wood has reached the proper softness.

What is the role of Safranin in the preparation of microtome slides?

Safranin is a dye used to stain the wood slices, highlighting the cell walls. It allows for better visualization of the anatomical structures during microscopic examination, as it binds to the cell structures.

Why is dehydration necessary after staining the wood slices?

Dehydration removes the water from the wood cells, which is crucial for preserving the sample and preventing it from deteriorating. This is done using graded alcohol solutions, from 10% to absolute ethanol, which gradually replaces the water.

What is the final step in preparing the microtome slide?

The final step involves placing the stained and dehydrated wood slice onto a glass slide, adding a cover glass, and securing it with an adhesive to preserve the sample for long-term microscopic analysis.

How are the prepared microtome slides examined?

The prepared slides are examined under a microscope that is connected to a computer, allowing for detailed imaging at various magnifications to study the wood's anatomical structure across different planes (tangential, radial, and cross-sectional).