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Separate Leopard Frogs

ACTSCI-TEEYYP

What information from the two data tables would you use to conclude that the Northern Leopard Frog and Southern Leopard Frog are indeed two separate species?


The Coughing Frog

Use the information below, as well as all the other collected data to answer this question.

Upon review of the scientific literature, the doctoral student discovers that there are two coding DNA sequences, known as genes, which lead to the making of proteins key to any frog being able to produce its characteristic croak. One gene product, called VB, allows for proper construction of the tissue that allows the frog to produce the croak. Another gene, called PC, adds a protein compound to the tissue which changed the pitch of the croak, giving each individual species its own particular sound, allowing the finding of a mate to be made easier.

This information sends the doctoral student back to the lab to begin another study. He obtains DNA from the coughing frog, Northern Leopard Frog, and Southern Leopard Frog. This time he uses a DNA sequencer to obtain the order of the nitrogen bases for both the VB and PC genes in each of the frogs. This allows him to obtain the following data:

Organism VB Gene Partial DNA Sequence
Coughing Frog ATGCCCTTATTCGCTACT
Northern Leopard Frog ATGCCCTTAAACGCTACT
Southern Leopard Frog ATGCCCTTAAACGCTACT
Organism PC Gene Partial DNA Sequence
Coughing Frog CCGATCATGGTTTTACCT
Northern Leopard Frog GCGTAGATGGTTTTACCT
Southern Leopard Frog GCGAAAATGGTTTTACCT

Key: A=Adenine, T=Thymine, G=Guanine, C=Cytosine

A

Differences in the VB gene sequence indicate they would produce different croaks due to different throat tissue structure.

B

Differences in the PC gene structure indicate they would produce different croaks due to the production of different croak pitches.

C

A combination of differences in the VB and PC structure indicate they would produce different croaks due to different throat tissue structure and different croak pitches.

D

Because the DNA sequences of both genes are identical, it is no longer correct to classify these two frogs as separate species.