Archive for June, 2012

Speed Dating with Gene Testing

Written by Kelly A. Hogan, University of North Carolina at Chapel Hill

Learning Outcomes:

– Evaluate the strength of the scientific studies presented at direct to consumer personal genomic testing services.

– Practice science communication through a two-minute discussion several times with different partners.

Activity Description: Students (for a class of approximately 30) are assigned prior to the activity one genetic test.  They will use the 23andme website to find out information about the gene test for their assigned trait/disease. During the activity, students follow a sort of “speed dating” protocol in which each student will meet with four other students (5 min each). After the four 5-minute sessions, students will be given an opportunity to choose other students’ presentations they found especially engaging.

Time Needed: 30 minutes in class

Materials Needed: Speed Dating with Gene Testing Homework and DNA Cards Worksheet

Activity Instructions: A week prior to the activity, assign each student to a genetic test (see the list and the student assignment attached). On the day of the activity, set up the classroom– make an inner circle and an outer circle of students, with equal numbers in each circle.  Randomly give five students one of the DNA cards before the activity begins. Each student is initially paired with and talks to another student for a total of 5 minutes. During this time, they each get about 2 minutes to tell each other what they learned.

While talking, each pair should have the list of “question prompts,” but they should not have their own notes out. They can each talk for two minutes straight or they can go back and forth for the 5 minutes. They can decide as a pair initially.

When the buzzer sounds, students in the outer circle rotate and meet with the next student for another 5 minutes. Repeat two more times, such that each student has spoken with four students over the course of 20 minutes. (Rather than a circle, you might try two rows of students in which one of the two rows moves every 5 minutes).

After the four 5-minute sessions, each of the five students with a card chooses one person they found especially engaging by giving them their DNA (a picture card, analogous to a reality show and a rose; see attached). Ask them to explain why. This is meant to get the discussion started, but others might want to also tell what they found most engaging.

Print an image like this to make the DNA cards:

 

 

 

 

 

 

Assessment:

Q: If an Asian male wanted to be tested by 23andme, would the results be applicable to him? Explain why or why not.

A: Yes and no. Many of the tests have been validated by studies of specific ethnicities but the studies have not been replicated in all populations. This does not mean that the results won’t hold true in other ethnicities, but there are limitations to the current knowledge. Nonetheless, many tests have been validated in multiple ethnicities. The site clearly states this for each gene test, so he can look to see which have been specifically validated in Asians.

Vertebrate Phylogeny

Written by Kelly A Hogan, University of North Carolina at Chapel Hill

Learning Outcomes:

– To describe how phylogenetic trees show evolutionary relationships

– To describe shared characteristics in vertebrate evolution

– To construct a simple phylogenetic tree for mammalian evolution

Activity Description: This activity can be used while teaching vertebrate evolution. It will also bring in phylogeny, as a way for students to see relationships rather than lists of characteristics to memorize about vertebrate. Students will explain phylogenetic trees, practice with the vertebrate phylogenetic tree they have seen in their textbook, and then construct their own tree to demonstrate their understanding of phylogeny. After the worksheet, an assessment question (see below) can be used b the instructor in various ways.

Time Needed: 15-20 minutes

Materials Needed: The activity worksheet can be printed for class time. A key is also attached. An optional “Guided Reading Questions” worksheet accompanies the activity for students to do on their own while reading to prepare for this day’s activity.

Vertebrate Phylogeny Worksheet

Vertebrate Phylogeny Worksheet KEY

Guided Readings Questions for Vertebrate Evolution

Activity Instructions: Students should read about vertebrate evolution before this activity. Students work through the worksheet and are then given the assessment below.

Assessment: The following assessment is adapted from an “Applying the Concepts” Question in Chapter 15 of Campbell Biology Concepts and Connections 7th Edition. It can easily be modified into a set of clicker or multiple choice exam questions.

Directions: Arrange the species on the phylogenetic tree below and indicate the derived character that defines each branch point.

Numerous questions can be made for clicker or test exams for students to make correct labels. Example:

What should be at label “Z”?

A)    Fur

B)     Green Skin

C)    Bleeker

D)    Suction Cup Feet

E)     Giant Eyes

Answer: D

Key: for all labels:

W – Green Skin

X – Giant Eyes

Y – Fur

Z – Suction Cup Feet

1- Bleeker

2- Floof

3- Snoozle

4- LooHoo