Use the Following to Answer Questions

question 11

Multiple Choice

Use the following to answer questions :
The diagram below shows the association of phenotype and gene expression patterns in five different species. The top portion shows the phylogeny of the five species; below the phylogeny are the phenotypes of the five species; and at the bottom are the expression patterns for three different genes (genes 1, 2, and 3) at two different time points in development (early and late) , and in two different locations in the embryo (top and bottom) .
-Which gene's expression is associated with the additional segment seen in species B and E?

• A) Gene 1
• B) Gene 2
• C) Gene 3
• D) Both gene 1 and gene 2
• E) Both gene 2 and gene 3

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Definitions:

Keystone Species

A vital species within an ecosystem whose presence significantly influences the biodiversity and stability of the environment.

Exotic Species

Organisms introduced to a new habitat where they are not naturally found, often causing harm to the local ecosystem and native species.

Indicator Species

Species that serve as a sign or indicator of the health or condition of an ecosystem, often sensitive to environmental changes.

Endemic Species

Species that are native to a specific geographical area and found nowhere else in the world.