The Constituents of the Electron Transport Chain Have Similar Capabilities,with

question 3

Multiple Choice

The constituents of the electron transport chain have similar capabilities,with the exception of ubiquinone (coenzyme Q) .What is different about ubiquinone?

• A)Ubiquinone is a protein that begins the electron transport chain,so it accepts the highest-energy electrons.
• B)Ubiquinone is a protein that serves as a regulator of the rate of redox reactions in the electron transport chain.
• C)Ubiquinone is a protein that is a constituent of all cells,prokaryotic or eukaryotic;hence its name originating from "ubiquitous."
• D)Ubiquinone is lipid soluble and so can move through the inner mitochondrial membrane.

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Definitions:

CAMP

Cyclic adenosine monophosphate; a second messenger important in many biological processes.

Protein Kinase

Class of enzymes that phosphorylates other proteins. Many of these kinases are responsive to other chemical signals (e.g., cAMP, cGMP, insulin, epidermal growth factor, calcium, and calmodulin).

Intracellular Mediator

Molecules inside cells that transmit signals from a cell receptor to a target, playing a key role in cell signaling pathways.

Hormonal Secretion

The release of hormones into the bloodstream by endocrine glands, which then travel to target organs or tissues to exert their effects.