Use the following information to answer the question. In order to test how sea urchin sperm bind to eggs, scientists isolated the egg receptor protein

that binds to the sperm acrosomal protein called bindin. Plastic beads were coated with egg receptor for bindin (ERB1) from eggs of the sea urchin Strongylocentrotus purpuratus, and then the beads mixed with sperm from S. purpuratus or from the related species, S. franciscanus. The researchers counted how many sperm were bound to each bead. The results are shown in the graph below. Treatments:

A: S. purpuratus sperm mixed with S. purpuratus ERB1 beads

B: S. purpuratus sperm mixed with beads containing no ERB1 protein

C: S. franciscanus sperm mixed with S. purpuratus ERB1 beads

D: S. franciscanus sperm mixed with beads containing no ERB1 protein

Based on the data in the graph, which of the following conclusions is supported?

TLS Online TPP Program

#Question id: 12228

#Unit 10. Ecological Principles

Which of the following examples best describes an ecological community?

TLS Online TPP Program

#Question id: 12229

#Unit 10. Ecological Principles

Community ecologists would consider which of the following to be most significant in understanding the structure of an ecological community?

TLS Online TPP Program

#Question id: 12230

#Unit 10. Ecological Principles

Historically, most ecological research on the community has focused on which of the following? 

TLS Online TPP Program

#Question id: 12231

#Unit 10. Ecological Principles

Which of the following studies would a community ecologist undertake to learn about competitive interactions? 

TLS Online TPP Program

#Question id: 12232

#Unit 10. Ecological Principles

White-breasted nuthatches and Downy woodpeckers both eat insects that hide in the furrows of bark in hardwood trees. The Downy woodpecker searches for insects by hunting from the bottom of the tree trunk to the top, while the White-breasted nuthatch searches from the top of the trunk down. These hunting behaviours best illustrate which of the following ecological concepts?

TLS Online TPP Program

#Question id: 12233

#Unit 10. Ecological Principles

Monarch butterflies are protected from birds and other predators but the cardiac glycosides they incorporate into their tissues are from eating milkweed when they were in their caterpillar stage of development. The wings of a different species of butterfly, the Viceroy, look nearly identical to the Monarch so predators that have learned not to eat the bad-tasting Monarch avoid Viceroys as well. This example best describes