Volume 79, Issue 3. Previous Article Next Article. The Models. Proposed Activities. Appendix 1. Article Navigation. Research Article March 01 ERIC J. This Site. Google Scholar. Monique M. Williams ; Monique M. Eric J. Ross ; Eric J. Sofia M. Robb ; Sofia M. Sarah A.
Elliott ; Sarah A. Kimberly C. Tu ; Kimberly C. The American Biology Teacher 79 3 : — Get Permissions. Cite Icon Cite. Figure 1. View large Download slide. Figure 2.
Figure 3. Table 1. Species-specific planarian features. Head shape and Auricles. Auricles: Short and broad. Dorsal side: Almost uniformly brown with irregularly dispersed white splotches. Ventral side: Lighter than the dorsal side. Dugesia dorotocephala 30 mm long and 3. Auricles: Elongated, sharply pointed, extended laterally, and held elevated while the worm is moving. Dorsal side: Composed of spots of various shades of brown, white, and black. Phagocata morgani 14 mm long and 2 mm wide Head: Rectangular with truncated anterior end and rounded lateral edges.
Auricles: Flattened along the head. Dorsal and ventral sides: White because of the lack of pigmentation. Phagocata gracilis 8—30 mm long and 1. Head: Truncated at the anterior end with slightly bulging frontal margin. Auricles: Rounded and protruding laterally at the anterior end of the head. Dorsal side: Dark brown to almost black. Ventral side: Somewhat lighter than the dorsal side.
The pharynx cavity contains multiple pharynges. View Large. Figure 4. Table 2. Activity suggestions. Can you see the gut branches if you add food coloring to the food? How many days after amputation do worms start eating again? Note: Do not put too much food in the dish while the worms are regenerating as they may become sick.
A sick worm develops dorsal lesions Fig. What is the smallest piece of tissue that can regenerate a complete animal? Can you produce any regeneration abnormalities from certain types of cuts such as double-headed or double-tailed worms?
What is the behavior of the regenerating fragments over time i. How might the environment i. Can a ribo probe specific to one species also work with other species? Are you interested in a specific gene?
Can you find the homologous sequence in a planarian transcriptome database and design specific primers? How can you clone a gene of interest and design a ribo probe using the suggested sequence or sequences?
Note: The RNAi-fed worms can be split into two groups: the first for monitoring homeostasis phenotypes in intact worms, and the second for following the regeneration phenotypes after amputation. Does the phenotype emerge at the same time in both groups, and what might this mean?
Which other genes would you like to try to knock down? What phenotype do you expect? Can you find homologous sequences in planarians and design specific primers using the available transcriptomes? Can you clone your own gene and transform the bacteria or synthesize and purify the dsRNA using the suggested sequences or sequences you may be interested in? What happens if you try to feed Girardia sp.
What happens if you try to feed P. Note: Feed one group of worms, Girardia sp. B and C above : Visualization of Gene Expression WISH after Amputation Goals: Multiphase experiment set-up; acquisition of ability to correlate different regeneration stages with planarian internal anatomy and gene expression.
What is the internal organization of the worms during regeneration? How are the organs remodeled in the regenerating fragments? What is the internal organization of abnormal animals produced by amputation? After odf2 RNAi , are there any neural defects? After odf2 RNAi , are there any muscular defects?
Figure 5. Figure 6. Figure 7. Figure 8. Table 3. Function and expression localization of genes used for the WISH protocol. Tissue specific expression. As a general policy, we do not advocate the release of organisms into the environment. In some states, it is illegal to release organisms, even indigenous species, without a permit. The intention of these laws is to protect native wildlife and the environment. Tap water often contains metal ions that are detrimental to planarians.
During their sexual period, generally February or March, black and brown planarians are fragile. Do not handle or feed them during this time. They may deposit cocoons on the bottom of the culture dish.
If maintained in fresh spring water, the cocoons will hatch in 2 to 3 weeks, giving rise to several small planaria. The anterior end of the planarian is more sensitive to toxins; if a toxic substance is in the water, the anterior end will degenerate first. Use spring water, not tap water. If you are using spring water from a grocery store, there may be a problem with it.
Locally collected spring or pond water may contain a pollutant, or your containers may have soap or detergent residue in them. Which planarians should I use for regeneration experiments? Black and brown planaria are your best choice. It will take them about 2 weeks to regenerate at room temperatures.
White planaria will regenerate, but they take longer. Black planaria are difficult to find in the spring, so we may substitute brown for black. We want you to have a good experience.
Orders and replacements: Technical support and questions: caresheets carolina. We use cookies to provide you with a great user experience. By using our site, you accept our use of cookies. You can review our cookie and privacy policy here. Login or Register Account Login or register now to maximize your savings and access profile information, order history, tracking, shopping lists, and more. Account Account. International Ordering Information. Login Create an Account.
My Cart Your Shopping Cart is currently empty. Menu Search by Keyword or item. New - Preserved Organisms. New - eLearning Resources. New - Biotechnology. New - Chemistry. New - Life Science. Phenomenal Explorations. Biotechnology New - Biotechnology. Biotech Kits. DNA Extraction. BBS Kits, Grades BBS Literacy Series. We have created a table of Primers for each of the four species utilized in the provided Protocols.
You can find information about the gene function and the sequence used to generate our primers by clicking on the gene names and opening the gene page. There is a "Sequence" tab on each gene page where the mRNA, coding, and protein sequences can be found. You can use the mRNA sequence as a starting point for cloning the genes yourself.
We also have detailed Laboratory Protocols, which will help you to explore the world of science using planarians as your guide. The Protocols can be found in the sidebar. If there are words that you do not know, check the Glossary of Terms , several technical expressions are explained in this page. If the word that you were looking for is not there? Tell us at cuttingclass stowers. We also provide you with Useful Links. Here you can go to websites where you can find more information about planarians, the institutes that funded this project, and us.
Planaria flatworms can be found in fresh water ponds especially during spring. The teacher can get some flatworms in these ponds for the experiment. There are also shops that sell biological supplies including planarian flatworms. The teacher can buy some flatworms in these shops. The flatworms should be kept in glass containers with some water preferably spring water before the experiment. The flatworms need water to prevent dehydration. Before the experiment, the teacher should explain clearly the objective s of the experiment to the students.
The main objective of course is to demonstrate regeneration. The class can be divided into groups where each group will set up their own experiment or there would only be one set up for the whole class depending on the number of flatworms or materials available. The teacher may instruct the students to observe the anatomy of the flatworms and the movement of the flatworms. The teacher can also ask the students to draw and label the flatworms.
The teacher will demonstrate to the class on how to dissect the flatworms into multiple parts.
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