Biological Effects of Radiation
Lesson 10 of 13
Objective: Students will be able to explain how radiation can harm the human body and how to guard against it.
Unit Overview: This unit, called Passion, Power, and Peril, is an inter-disciplinary unit between two classes—English and Chemistry. In Chemistry class, students will learn about nuclear chemistry, but they will also research a specific aspect of the nuclear power industry. They will use this research in three ways. First, they will write a one-page paper for a Chemistry grade that explains how nuclear chemistry connects to the research topic. Second, students will write an informative/explanatory research paper that answers your research question by showing the complexity of the issue for an English grade. Finally, students will use their research and writing to create a piece of artwork for a multimedia art display designed to challenge the audience with weighing the costs and benefits of nuclear technology.
In this process we would like students to consider the following questions: How does society evaluate costs and benefits of a technology? What are the costs and benefits of nuclear power plants?
Lesson Overview: In this lesson students will read and take notes about the biological effects of radiation. This lesson is important to the overall unit because the potential for radiation leaks is one of the key reasons why there is opposition to nuclear power.
This lesson aligns to the NGSS Disciplinary Core Idea of HS-PS1-8. Develop models to illustrate the changes in the composition of the nucleus of the atom and the energy released during the processes of fission, fusion, and radioactive decay because it focuses on the biological effects caused by radioactive decay.
It aligns to the NGSS Practice of the Scientist of Obtaining, evaluating, and communicating information because students will need to gather information and then evaluate it in terms of how it relates to their research project.
It aligns to the NGSS Crosscutting Concept of Energy and Matter because energy cannot be created or destroyed—it only moves between one place and another. The concern is that high energy particles have the ability to cause mutations in DNA, which can lead to cancer.
In terms of prior knowledge or skills, students should have a basic understanding of nuclear decay, which they studied in this lesson.
There are no special materials needed in this lesson but access to a computer would be helpful; otherwise photocopying an article is required.
Do Now: Students start class by making some observations with one another about the graphic called Radiation Exposure.
I reason that this is a good way to start class because I want them to start seeing some of the vocabulary and issues that will be at the heart of today’s lesson. I like that the picture is visually interesting to look at, and it is interesting.
Activator: I then show a video about the use of Polonium 210 in the assassination of Alexander Litvinenko. We then have a discussion about radiation. Some students want more background on the Litvinenko case, and I answer questions about that.
The general prompt is, "What do you gather about radiation’s effect on the human body?" Students note that it is harmful above a certain dose, and that it can kill you or make you very sick, depending on the dose.
I figure that by now I have certainly gotten students attention, and I move to explaining what students will do today.
Mini-lesson: First I show them the Biological Effects of Radiation Reading questions that I want them to work on. I show that the website is easy to navigate and the questions come right from the website. I also explain to them that there ultimate goals are to not only understand how radiation effects people and other organisms, but also to be able to explain how it relates to their research topic.
Because this is a very straightforward assignment, students begin work without needing further guidance. I encourage them to help each other out and get this part of the assignment done as quickly as possible. For teachers who do not use the textbook A Natural Approach to Chemistry, this website may be of assistance in answering the final questions.
Student Activity: Students work on reading the website and answering the reading questions. I walk around and check in with students, but due to the nature of the way the website is set up, students can click on the question on the website if they are unsure of where to find the information.
While I think this is a fairly easy assignment, I think it is an important one in light of the fact that we are towards the end of our unit about how to evaluate nuclear power. I feel that this is an efficient way for students to get this important information.
Having students read text in order to obtain and analyze information, and then be able to communicate it to others, either orally or in writing, is an important academic skill.
Catch and Release Opportunities: One thing that confused students was the difference between stochastic and nonstochastic health effects. (Stochastic effects result from long term and low levels of radiation exposure, while nonstochastic health effects arise from acute exposure.) Because I was not familiar with these terms, I conducted a think aloud, where I read to myself out loud and interpreted what I was reading. This mirrors what would be going on in my brain as a reader, so I was glad to have an excuse to model what good readers do.
To wrap this lesson up I review the reading questions by calling on different students to read questions and answers. I remind students that radioactivity is one of the big issues that unclear opponents raise when discussing nuclear power, as shown in this video about how our work today relates to the nuclear research project.
I then explain how today’s lesson relates to the research project. As part of student’s final assessment for this unit, they have to relate all of the concepts they learn from the book to their research project. I go over this expectation by reviewing the document Nuclear Chemistry Open Response.
By bringing students back once again to the unit's overarching theme, I create a strong link between the different lessons in the unit.