Lab Report

Environmental Epigenetics Lab

Answer the following questions about the results of this lab activity. Record your answers in the boxes with the questions.It is important to discuss how and why the Coenorhabditis elegansimages differ from each other. Use the chart and images below as references for your answers.

Chemicals used in lab / Description
Epigenetic Factor dbl-1 / Known to affect a growth factor gene that controls body size
Epigenetic Factor db1-/Pha-2 / A mixture of epigenetic factor dbl-1 and Pha-2 which is known to affect the development of the pharynx (throat region near head)
Epigenetic Factor Let- 7 / Known to cause lethal aberrations during development by affecting body development genes
Mebendazole / A drug used to control disease-causing worms
Environmental Toxin 1 / Anherbicide used in agricultural weed control
Environmental Toxin 2 / A pesticide used in agricultural crop insect control

Use the image of the normal worm below to help identify the variations in the worms that you have viewed in the three experiments.

Phase Contrast – Coenorhabditis elegans

Send your completed lab report to your instructor. Don’t forget to save your lab report to your computer!

Activity 1 – Inducing Epigenetic Change

Answer the following questions about the results of this lab activity. Record your answers in the boxes with the questions. It is important to discuss thedifferences in the worms viewed under the microscope. You can draw the worms or cut and paste the images of the worms into the lab report document. It is also important to record all of the data from the DNA analysis.

Worm Images

Sample / Description of worm / Drawing or copy of worm image
Control - Untreated worm
(Culture Plate 1)
Epigenetic Factor dbl-1
(Culture Plate 2)
Epigenetic Factor db1-/Pha-2
(Culture Plate 3)
Epigenetic Factor Let- 7
(Culture Plate 4)

DNA Analysis

Sample / % Mutations / % Methylation
No treatment
Vial 1 before
Vial 1 after
Epigenetic Factor dbl-1
Vial 2 before
Vial 2 after
Epigenetic Factor dbl-1/Pha-2
Vial 3 before
Vial 3 after
Epigenetic Factor Let-7
Vial 4 before
Vial 4 after
  1. Use the description of each epigenetic factor to explain how the worms were affected by the particular epigenetic factor.

  1. Epigenetic Factor Let-7 causes the same effects in the worms as a DNA mutation called Let-7. Explain why the mutation is very rare in Coenorhabditis elegans unlike the mutation that produces the same effect as dbl-1.

  1. Using the information from the DNA analysis and your textbook or internet resource, explain why the relationship between mutations, methylation, and the changes seen in the worms.

Activity 2 -Environmental Epigenetic Change

Answer the following questions about the results of this lab activity. Record your answers in the boxes with the questions. It is important to discuss the differences in the worms viewed under the microscope. You can draw the worms or cut and paste the images of the worms into the lab report document.

Worm Images

Sample / Description of worm / Drawing or copy of worm image
Control –
Untreated
(Culture Plate 1)
Environmental toxin 1
(Culture Plate 2)
Environmental toxin 2
(Culture Plate 3)
  1. Use the description of each environmental toxin to explain how the worms were affected by the toxin.

  1. Explain if any of the toxins produced have effects similar to the epigenetic factors tested in Activity 1.

  1. Discuss why it is important to know if chemicals used to control pests in the environment cause mutations or epigenetic effects on model animals such as Coenorhabditis elegans.

Activity 3 -Epigenetic Inheritance

Answer the following questions about the results of this lab activity. Record your answers in the boxes with the questions. It is important to discuss the differences in the worms viewed under the microscope. You can draw the worms or cut and paste the images of the worms into the lab report document.

Worm Images1 - Adults

Sample / Description of worm / Drawing or copy of worm image
Adult Coenorhabditis elegans
Control –
Untreated
(Culture Plate 1)
Epigenetic Factor dbl-1
(Culture Plate 2)
Mebendazole
(Culture Plate 3)
Environmental Toxin 2
(Culture Plate 4)

Worm Images 2 - Offspring

Sample / Description of worm / Drawing or copy of worm image
Offspring Coenorhabditis elegans
Control –
Untreated
(Culture Plate 1)
Epigenetic Factor dbl-1
(Culture Plate 2)
Mebendazole
(Culture Plate 3)
Environmental Toxin 2
(Culture Plate 4)

  1. Use the description of EpigeneticFactor dbl-1 and Environmental Toxin 2 to explain the effects of mebendazole on the adult worms.
  1. Use the results of the offspring worms to discuss which treatments showed evidence of epigenetic effects on the worms. What additional tests would need to done to show that mebendazole works by causing epigenetic change?

  1. Compare and contrast the possible long term consequences to animals exposed to mebendazole and Environmental Toxin 2.