Gizmo

Name: ______________________________________ Date: ________________________

Student Exploration: DNA Fingerprint Analysis

Vocabulary: codon, DNA, DNA fingerprint, genotype, identical twins, nitrogenous base, phenotype, trait

Prior Knowledge Questions (Do these BEFORE using the Gizmo.)

1. The two navy officers shown at left are identical twins. Why do you think identical twins look so similar?

_______________________________________________

_______________________________________________

2. Most brothers and sisters don’t look exactly the same. What causes most siblings to have different appearances?

_______________________________________________

_______________________________________________

Gizmo Warm-up
Most of an organism’s traits, or characteristics, are coded for by DNA. Traits are determined by a unique sequence of nitrogenous bases in the DNA molecule.

Except for identical twins, the order of every individual’s nitrogenous bases is unique. Scientists use this fact when studying DNA fingerprints—patterns of bands made from analyzing a strand of DNA. In the DNA Fingerprint Analysis Gizmo™, you will analyze DNA fingerprints of frogs.

1. Select the POPULATION tab. What are the three main traits that vary between the frogs?

_________________________________________________________________________

2. Which frog would you expect to have the most similar DNA to frog A? Why? ____________

_________________________________________________________________________

|Activity A: |Get the Gizmo ready: |[pic] |
| |Select the FIND THE TWINS tab. |