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TLS Online TPP Program

#Question id: 5648

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

 What is a broader implication from the observations of the experiment?

#Unit 5. Developmental Biology

  1. In sea urchins, fertilization of eggs by sperm is dependent upon species-specific protein interactions.

  2. Only some species of sea urchins use receptor proteins on their eggs to bind sperm.

  3. Protein-coated plastic beads should not be used to test sperm binding to eggs.

  4. S. franciscanus is probably not a sea urchin, but must be some other type of organism.

More Questions
TLS Online TPP Program

#Question id: 1851

#Unit 4. Cell Communication and Cell Signaling

Which of the following is a feature of a Salmonella-based vaccine expressing antigens from other infectious agents?
TLS Online TPP Program

#Question id: 930

#Unit 1. Molecules and their Interaction Relevant to Biology

Ketone bodies are formed in the liver and transported to the extrahepatic tissues mainly as:
TLS Online TPP Program

#Question id: 20399

#Unit 12. Applied Biology

In T-DNA where are these right border and left border sequence present?
TLS Online TPP Program

#Question id: 449

#Unit 1. Molecules and their Interaction Relevant to Biology

The standard free-energy changes for the reactions below are given. Phosphocreatine -> creatine + Pi DG'° = –43.0 kJ/mol ATP ->  ADP + Pi DG'° = –30.5 kJ/mol What is the overall DG'° for the following reaction? Phosphocreatine + ADP -> creatine + ATP
TLS Online TPP Program

#Question id: 4679

#Unit 3. Fundamental Processes

Activated RecA stimulates autocleavage of