Pengamatan Mitosis Pada Akar Bawang dengan Metode Squash

Scorbia 21

19 Jul 202006:17

Summary

TLDRIn this educational video, viewers are guided through the process of observing mitosis in onion root tips. The tutorial begins with cultivating the roots in a damp environment or water to encourage growth. The roots are then treated with a 0.02% colchicine solution to inhibit spindle formation and enlarge chromosomes. Afterward, a Carnoy's solution is used for cell fixation. The video covers the preparation steps, including hydrolysis and staining with aceto-orcein, to reveal the chromosomes. Finally, the observer can examine the different stages of mitosis—prophase, metaphase, anaphase, and telophase—under a microscope. The video concludes with tips for preserving the samples for future observation.

Takeaways

🧬 The video script discusses observing mitosis in onion root tips.
🌱 The first step is to grow onion roots by placing them in a moist area or submerging them in water.
🔪 The bottom part of the onion is cleaned to ensure quick root growth.
💧 The root tips are then placed in a 0.02% colchicine solution for 1-2 hours to inhibit spindle formation and enlarge chromosomes.
🧪 After colchicine treatment, the solution is replaced with Carnoy's solution for 2-3 hours to fix and preserve the cell condition.
🚫 If immediate observation is not needed, the sample is stored in 70% alcohol for preservation.
🔬 The purpose of the treatment is to break down cell walls to facilitate the observation of mitotic division.
🔥 The sample is then hydrolyzed in a reaction tube at 60°C for 15 minutes, followed by rinsing and staining with 2% aceto-orcein.
🎨 The staining process takes 15-30 minutes or more, depending on the sample condition.
🔍 After staining, excess stain is washed off with 45% acetic acid, and the slide is prepared for observation under a microscope.
📸 The video suggests using a 100x objective lens for observation and applying immersion oil to the cover glass for clarity.
🖼️ The results of the mitosis observation can be preserved using a glass slide and a cover slip for permanent and repeatable viewing.

Q & A

What is the main topic of the video script?
-The main topic of the video script is learning how to observe mitosis by studying the root tips of an onion.
How should the onion root be prepared for mitosis observation?
-The onion root should be prepared by placing it in a damp area or submerging it in water to encourage root growth. The bottom part of the onion should be cleaned to facilitate quick root development.
What is the purpose of using a 0.02% colchicine solution in the process?
-The 0.02% colchicine solution is used to inhibit spindle fiber formation during cell division and to enlarge the chromosomes for easier observation.
What is the role of Carnoy's solution in the preparation process?
-Carnoy's solution is used to fix or preserve the condition of the cells after colchicine treatment, ensuring the cells are kept in a stable state for observation.
Why is it necessary to store the sample in 70% alcohol if not observed immediately?
-Storing the sample in 70% alcohol preserves it for future observation, allowing it to be kept for weeks or months without immediate analysis.
What is the purpose of the hydrolysis step in the preparation process?
-The hydrolysis step is intended to break down the intercellular bonds, making it easier to observe the mitotic divisions in the cells.
How long should the root be kept in the oven during the hydrolysis process?
-The root should be kept in the oven for 15 minutes at a temperature of 60°C during the hydrolysis process.
What is the function of aceto-orcein as a stain in the preparation process?
-Aceto-orcein is used as a stain to color the chromosomes, allowing for optimal absorption of color for clear observation under a microscope.
How long should the stained sample be left to absorb the color before observation?
-The stained sample should be left to absorb the color for 15-30 minutes, although the time may vary depending on the condition of the sample.
What should be done to clean the excess stain before observation under a microscope?
-The excess stain should be cleaned off with 45% acetic acid, followed by rinsing and blotting with a tissue to prepare the slide for clear microscopic observation.
How can the results of the mitosis observation be preserved for future reference?
-The results of the mitosis observation can be preserved by using a glass slide and cover slip, which makes the preparation permanent and allows for repeated observation.

Outlines

00:00

🌱 Observing Mitosis in Onion Root Tips

This paragraph introduces a tutorial on how to observe mitosis in onion root tips. The process begins with cultivating onion roots by placing them in a moist environment or in water to encourage growth. The roots are then treated with a 0.02% colchicine solution for 1-2 hours to inhibit spindle formation during cell division and to enlarge the chromosomes for easier observation. Afterward, the colchicine solution is replaced with Carnoy's solution for 2-3 hours to fix the cells. If immediate observation is not desired, the sample can be stored in 70% alcohol for extended periods. The purpose of these treatments is to break the cell wall bonds, facilitating the observation of mitosis in mosquito larvae. The process includes hydrolysis, cutting the root, and heating it in an oven at 60°C for 15 minutes. Afterward, the root is stained with a 2% aceto-orcein solution for 15-30 minutes to optimally absorb color. The excess stain is then washed off with 45% acetic acid, and the sample is prepared for observation under a microscope with a 100x objective lens and immersion oil.

05:13

🔬 Storing and Sharing Mitosis Observations

The second paragraph discusses the steps to store and share the results of mitosis observations. It mentions that the prepared slides can be preserved using Canada balsam or other mounting media to make them permanent and suitable for repeated observation. The paragraph also encourages viewers to support the tutorial by liking, commenting, and subscribing if they find the video helpful.

Mindmap

Keywords

💡Mitosis

Mitosis is a type of cell division that results in two daughter cells each having the same number and kind of chromosomes as the parent nucleus. It is crucial for growth, development, and repair in multicellular organisms. In the video, mitosis is the central theme, as the process is being observed in onion root tips to understand cell division.

💡Onion root tip

The onion root tip is used as a model system for observing mitosis due to its large, easily observable cells. In the script, the process of growing onion root tips in moist conditions or water is described as the initial step for preparing samples to observe cell division.

💡Colchicine

Colchicine is a chemical that inhibits cell division by disrupting the formation of the spindle fibers during mitosis. In the video, a 0.02% solution of colchicine is used to enlarge the chromosomes, making them easier to observe under a microscope.

💡Chromosomes

Chromosomes are thread-like structures made of DNA and proteins that carry genetic information. They play a key role in mitosis as they are duplicated and distributed to the daughter cells. The script mentions the enlargement of chromosomes as a step in preparing the samples for observation.

💡Carnoy's solution

Carnoy's solution is a fixative used in histology to preserve the structure of cells and tissues. In the video, it is used to fix the cells after colchicine treatment, maintaining the cell's condition before further processing.

💡Alcohol 70%

A 70% alcohol solution is used in the script as a storage medium for samples that are not to be observed immediately. It helps to preserve the samples for a longer period, weeks or months, before observation.

💡Hydrolysis

Hydrolysis is a chemical process that uses water to break down molecules. In the context of the video, it is mentioned as a step to break down the cell walls, allowing for easier separation of chromosomes during the staining process.

💡Aceto-orcein

Aceto-orcein is a staining solution used to color chromosomes, making them visible under a microscope. The script describes its application to the samples after hydrolysis, with a staining time ranging from 15-30 minutes for optimal color absorption.

💡Cover slip

A cover slip is a small, thin piece of glass placed over a specimen on a microscope slide to protect the sample and allow light to pass through for viewing. The script includes instructions on how to properly place a cover slip over the stained cells for observation.

💡Phases of mitosis

The phases of mitosis include prophase, metaphase, anaphase, and telophase. These are the stages through which a cell nucleus passes during cell division. The video script describes observing these phases as part of the mitosis observation process.

💡Permanent slide

A permanent slide is a prepared microscope slide that can be preserved and observed multiple times. The script mentions the use of a mounting medium to create a permanent slide of the mitosis observation, allowing for repeated examination.

Highlights

Introduction to observing mitosis at the tip of an onion root.

Growth of onion roots by placing them in a damp area or submerging them in water.

Cleaning the bottom part of the onion to ensure rapid root growth.

Use of a 0.02% colchicine solution to inhibit spindle formation during cell division.

Purpose of colchicine treatment to enlarge chromosome size for easier observation.

Rinsing off colchicine and replacing it with Carnoy's solution for cell fixation.

Storage of samples in 70% alcohol for preservation if not observed immediately.

Explanation of the purpose of treatment to break intercellular bonds for easier observation.

Hydrolysis process using a reaction tube and oven treatment at 60°C for 15 minutes.

Careful not to dry out the root during the hydrolysis process.

Use of 2% aceto-orcein stain for optimal color absorption during observation.

Duration of staining can vary depending on the sample condition.

Rinsing off excess stain with 4-5% acetic acid to clarify the sample for observation.

Preparation of a slide by covering with a cover glass and ensuring no particles are on the sample.

Technique to prevent breaking the glass slide or cover glass during observation.

Observation of mitosis phases: prophase, metaphase, anaphase, and telophase.

Instructions on how to save the results of mitosis observation for repeated viewing.

Encouragement for viewers to like, comment, and subscribe if they find the video helpful.