HIV project - Assessment
Students will be able to research and find possible solutions to a problem using a biological database.
Students will be able to read and understand amino acid sequences and alignments produced by Biology Workbench.
Students will be able to identify common mutation locations in HIV-1 envelope proteins and human CD4 proteins and make research/treatment recommendations based on this information.
In this lesson the students have been asked to research two problems concerning HIV-1 envelope glycoproteins and human t-cell CD4 proteins using Biology Workbench for Students. The assessment activity for this project is a poster session, where each research team presents their research findings and recommendations to the rest of the class. Their posters and presentations need to include the following things.
It’s really important in this lesson to include a form of assessment in which the students have both a written (poster) section and a verbal (presentation) section. The written part insures that the students have thought about and organized the information they have been working on in the course of this research project. It also provides the teacher with a tangible object for grading that can be looked at with more detail and scrutiny than a presentation alone. The presentation is equally important though, because it checks to see that students can do two things. First of all, they have to be able to communicate their ideas to other people, and in order to do this, they have to have a very good command of those ideas. In other words, they have to have thought them out fairly thoroughly. Also, they will have to defend their ideas to the rest of the class since a questioning aspect is built into the presentation (see below).
1. Introduction/methods: In this section the students will have to explain what the purpose of their project was. That is, why were they doing this research? They will also need to describe how they went about their research: how they decided which protein sequences to align, what tools they used on the sequences and why, etc.
This section requires that the students put some thought into how they go about their research. My experiences have been that students often go about research of this type in a somewhat haphazard manner, at least at first. Including this section on the poster not only insures that an independent reader would be familiar with the problem, but also that they have thought through their research before they started.
2. Data: For each question, the students will need to include data they gathered through their research on their poster, and refer to it during their presentation. Data may include print outs of amino acid sequences and alignments, inferred phylogenetic trees, or any other data the students generate to support their conclusions.
3. Conclusions: For each question, the students will also need to include a conclusion section, both on their poster and in their presentation. This section includes the recommendations the teams are proposing based on the research they have done. These recommendations should answer the questions posed:
a. Find and compare amino acid sequences of HIV envelope protein taken from various patients to determine which portions can be targeted for treatment and which portions mutate too often. Does the virus mutate predictably so that we can target one area? Or is it unpredictable so that we need to target several different areas? What are your treatment recommendations? What kinds of mutations are occurring? Substitutions? Deletions? Insertions?
b. We learned earlier that some people can resist infection by HIV because they have a mutation on their CCR5 proteins. We also learned that HIV has to bind to two different proteins on the surface of T-cells, and that the other protein is called CD4. Are there significant differences in the amino acid sequences from one person to another that it might be possible that a mutation exists for the CD4 protein that also might make some people resistant? Are there other species of animals that have a protein similar to the CD4 protein in humans where HIV binds to T cells that we could use for researching treatment options or searching for HIV resistant strains of CD4? What animals have proteins most similar to us? How similar are they, and where do they differ?
The students could possibly answer some of the questions posed above without really having a good command of Biology Workbench or the data that it produces. By stressing that their conclusions must refer to and be supported by the data that they include in the data section of their poster, it is much more likely that the students will really need to understand what that data means. They will need to be able to read the alignments produced and understand the significance of what they are seeing. They will also have to be able to use the various other tools on Biology Workbench in order to find out what data is most significant and what data is less so.
As each team presents their research, the other students in the class will be responsible for critiquing that team’s poster and presentation, using the rubric attached. The major focus for these critiques should be on the data and conclusions presented, specifically on how well the data supports the conclusions. The students will also have to make written comments (apart from just the number score) in order to justify the scores that they give to their classmates.
Sometimes it is really easy for students to just give each other perfect or near perfect scores, either because they don’t have to put much thought into it, or because they would want to get the high scores themselves. I don’t think it’s very valuable to have the students assessing one another if they don’t really put some thought into it. One of the real benefits of having the students assign each other grades is that they get a chance to see for themselves how a presentation or a poster could be improved, what things really helped them to understand the team’s research, what things were a little unclear, and what could have helped them to understand more. They can then apply these things to their own future projects. However, these benefits are all lost if the students do not spend some time thinking about the grades they are assigning.
One problem I have historically had with this class is that they are very quiet, and have a hard time having class discussions. In order to combat this problem, I am making questioning one another’s presentations a requirement for this project. For each presentation, one of the other research teams in the class will be assigned to ask at least two questions at the end of the presentation. The floor will be open to anyone who wants to ask questions, but assigning a group to ask questions will hopefully get the ball rolling on the discussions.
In order to assign grades that accurately reflect the depth of research a team has done and knowledge that they have gained, in most cases it will be necessary for the students to ask questions of the presenters. Partly because of the very small class size, and partly because of the make up of the class, the students have a hard time questioning one another, which would interfere with the grading process. The teacher could always ask these questions, but it’s much more valuable for the students if they ask the questions themselves for a couple of reasons. First, questioning one another’s assertions helps them develop skills they can use to question other scientific ideas and models. Also, by having to think about another group’s research enough to ask questions about it, the students will also find ways in which they can improve their own research methods and presentations.
Part of the grade for each group will be an average of the scores given by the class, so that a portion of the grade reflects the students’ opinions. The rest of the grade will be assigned by the teacher, to counteract excessively high or excessively low grading by the students. The teacher will compile the scores and comments on a typed summary sheet to be handed out to the teams.
One problem I foresee with having the students assign grades and comments, especially in a class this small, is that they may not feel comfortable being entirely honest about their true impressions of a group’s presentation if that group will later see what they said. However, I do think that it is very valuable for the students to be able to give and receive honest feedback so that everyone can learn from each other. By giving each group a typed summary of the comments the class made, I can take care of both of these issues. The students will still be able to benefit from the opinions of the other students in the class, and I think most of them will feel more comfortable making comments when they aren’t worried about their handwriting being recognized. I also think that it is important for the students to receive feedback from the teacher, and this will be included as such on the summary sheet.