Genetic Mutations

Introduction

Welcome!

This week, you have learned a LOT! You have learned what DNA is made of, the job of RNA, and how proteins are made (protein synthesis). Today we are going to take a look at what happens if a mistake occurs in the formation of DNA.

Task

Your task, should you choose to accept it, (you have to, you don’t have a choice ;) is to investigate the following mystery. You will fill out your investigation report and then write up your findings in 2-3 paragraphs.

Mutant Frogs Spark A Mega Mystery

Scientists Worry Deformities Could Be An Early Warning Of Environmental Danger

August 04, 1998|By Amanda Vogt, Tribune Staff Writer

In the nation's wetlands, ponds and nature preserves, deformed frogs are turning up in record numbers.

Like other amphibian populations, the number of frogs has been declining for decades. That's reason enough for concern, given the delicate ecological balance between all living things.

But this latest development really has scientists worried. Why?

It all began in the summer of 1995, when a group of middle-school kids from the Minnesota New Country School in southern Minnesota made a startling discovery on a field trip to a local pond. They noticed that many of the pond's frogs were malformed. Some had weird-shaped or extra limbs and others were missing eyes or toes.

The kids reported their discovery to local wildlife officials, who contacted national environmental groups, and before long, deformed frogs were turning up all over the nation. They've been reported in 32 states.

Although the cause of the malformations remains a mystery, scientists have some theories.

Process

1)Go to Brain Pop and watch this video, then take the classic quiz about mutations. Write down your quiz score on your sheet.

http://tinyurl.com/jnhxv7k

2)Visit this website to find out what exactly what causes mutations. Make sure to watch the animation.

http://tinyurl.com/hrsxzde 

3)Play this game and try to match the DNA correctly to avoid mutations!

http://tinyurl.com/6k3hzj8

4) Watch this video and answer the part four questions on your sheet.

https://edpuzzle.com/media/56bc17a845531bd8287112c3

5) Interested in what this looks like in humans? Check out this video.

https://edpuzzle.com/media/56bc16df45531bd82871110c

Evaluation

Use the information you gathered to write your response to the mystery. What do you think could have caused the mutated frogs that have been found by students? Be sure to include what causes mutations, as well as possible effects of mutations. Could outside factors have played a role? You must have 2-3 7th grade paragraphs. No two sentences should say the same thing. =)

Conclusion

So here's the rest of the story...

Although the cause of the malformations in the frogs remain a mystery, scientists have some theories. They suspect that a change in the environment - caused either by global warming, pollution or exposure to ultra-violet radiation - may be triggering whatever is causing the mutations.

But with wildlife habitats disappearing daily due to human development, why are scientists so concerned about frogs?

"If you look across organisms, there are many similarities in how they handle" environmental stress, says George Lucier, director of the U.S. National Institute of Environmental Health Sciences' Toxicology Program. "What's toxic to frogs is often toxic to people."

Certain characteristics make the frog a barometer of environmental health - a sort of "early warning system" for all of Earth's creatures. Frogs live both in water and on land and breathe through their sensitive skin pores.

Unlike other species, "in their larval (tadpole) stages, they aren't protected by an eggshell or uterus," says Carol Meteyer, a wildlife pathologist with the U.S. Geological Society's National Wildlife Health Center.

In the years since the Minnesota kids' discovery, experts have put together several pieces of this puzzle.

After examining hundreds of tadpoles, Meteyer found that the deformaties occur during the developmental stages - as birth defects. (Malformed frogs older than 2 years are rare, she says, because few survive a single winter.)

Lucier says research indicates that the source of these birth defects is probably organic (from something living), like a plant-based chemical or pesticide. The scientists have successfully filtered the culprit from contaminated water, he says, so it's highly unlikely that it's bacterial (bacteria are microscopic).

U.S. scientists first suspected that a fungus responsible for killing frogs in Australia was deforming frogs in North America. Until a decade ago, this fungus did not cause disease in frogs.

Although they eventually ruled it out here, the fungus' ability to attack frogs now supports the theory that some change in the environment is behind the frog deformaties.

Once experts have identified what's killing frogs, they must identify the environmental changes that have allowed this culprit to evolve into a killer.

Then comes the hard part - figuring out how these changes could affect other species, including humans.

Were you correct???