A Biologist Discovers a New Signal Transduction Pathway in Fruit

question 149

Multiple Choice

A biologist discovers a new signal transduction pathway in fruit flies that involves a protein kinase cascade.As part of a grant proposal he writes to obtain funding for further work on this pathway, the biologist proposes research to look for phosphatase enzymes.Why?

• A) Since a signaling cascade contains multiple enzyme-catalyzed events, the biologist needs to identify all of the enzymes participating in the cascade.
• B) Since a phosphatase enzyme catalyzes the removal of phosphate ion from a substrate, the biologist needs to be sure that none are interfering with the signaling cascade.
• C) The biologist needs to identify the enzymes that provide the source of phosphate ions added to substrates during the signaling cascade.
• D) The biologist needs to identify the enzymes that regulate the pathway by removing phosphate groups from molecules in the signaling cascade.
• E) The biologist needs to identify all enzymes involved in phosphate ion transfer to determine whether they are involved in the pathway.

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Definitions:

Compound

A compound is a substance formed when two or more chemical elements are chemically bonded together.

Organic Product

A compound resulting from an organic reaction, often characterized by carbon-based structures.

Reaction

A procedure where compounds react to create new materials that have different characteristics.

Benzonitrile

An organic compound with the formula C7H5N, consisting of a benzene ring attached to a nitrile group.