Stromal Cell-Derived Factor 1 (SDF1) Is a Secreted Protein That

question 36

Multiple Choice

Stromal cell-derived factor 1 (SDF1) is a secreted protein that plays a major role in guiding the migration of various cells during development. It binds to a G-protein-coupled receptor on the surface of the migrating cell, which in turn activates a trimeric G protein containing a Gᵢ subunit. Pertussis toxin (PTX) modifies and inactivates the Gᵢ subunit. What would you expect to observe if migrating cells are treated with PTX?

• A) They migrate toward the source of SDF1.
• B) They migrate away from the source of SDF1.
• C) They migrate in a certain direction chosen randomly.
• D) They move in small steps in random directions.
• E) They lose their motility.

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Joint Cost Curve

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Economies of Scope

Cost advantages that enterprises obtain due to efficient resource utilization in producing a variety of products rather than specializing in a single product.

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The process of gaining skill or knowledge from direct experience or practice.

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The cost advantages that enterprises obtain due to their scale of operation, which often leads to a reduced cost per unit of output.