A Group of Investigators Is Studying the Mechanisms of Signal

question 107

Multiple Choice

A group of investigators is studying the mechanisms of signal transduction involved in the pathogenesis of type 2 diabetes mellitus.  Their research focuses on the intracellular signaling cascade that begins when insulin binds to the insulin receptor.  In a series of experiments, they demonstrate that pre-treatment with tumor necrosis factor alpha (TNF-α) results in decreased insulin-mediated glucose uptake.  This effect of TNF-α is most likely mediated through upregulation of which of the following processes?

• A)Cyclic AMP hydrolyzation
• B)Phosphatidylinositol cleavage
• C)Proline residue hydroxylation
• D)Serine residue phosphorylation
• E)Stimulation of peroxisome proliferator-activated receptor

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Definitions:

Kinked-Demand Model

A model in oligopoly markets, suggesting that firms might face a demand curve that has a sharp bend or "kink" at the current price, leading to sticky prices.

Price Rigidity

The situation in which prices do not change quickly in response to changes in demand or supply, remaining static despite market pressures.

Price Leadership Model

A market situation in which one leading company sets prices that other companies in the sector follow.

Antitrust Sanctions

Penalties imposed on businesses or individuals for violating antitrust laws, intended to promote fair competition and prevent monopolistic practices.