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. (Adapted from Kamei and Glabe 2003)
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

What is a broader implication from the observations of the experiment?
A) In sea urchins, fertilization of eggs by sperm is dependent upon species-specific protein interactions.
B) Only some species of sea urchins use receptor proteins on their eggs to bind sperm.
C) Protein-coated plastic beads should not be used to test sperm binding to eggs.
D) S. franciscanus is probably not a sea urchin, but must be some other type of organism.

Question

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. (Adapted from Kamei and Glabe 2003)
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

What is a broader implication from the observations of the experiment?
A) In sea urchins, fertilization of eggs by sperm is dependent upon species-specific protein interactions. 
B) Only some species of sea urchins use receptor proteins on their eggs to bind sperm. 
C) Protein-coated plastic beads should not be used to test sperm binding to eggs. 
D) S. franciscanus is probably not a sea urchin, but must be some other type of organism.

Quizplus · Accepted Answer

The experiment showed that only sperm from the same species as the egg receptor protein were able to bind to the coated beads. This suggests that for fertilization to occur in sea urchins, there must be species-specific protein interactions between the egg and sperm, implying a broader importance of such interactions in reproductive biology. Option B is incorrect as the experiment did not provide evidence that only some sea urchins use receptor proteins to bind sperm. Option C is incorrect as the use of protein-coated plastic beads was actually successful in testing sperm binding to eggs. Option D is incorrect as S. franciscanus is in fact a species of sea urchin.

Use the Following Information to Answer the Question