Which of the Following Is NOT Commonly Used as a Contrast

question 5

Multiple Choice

Which of the following is NOT commonly used as a contrast medium?

• A)Barium
• B)Air  
• C)Water
• D)Iodine

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Definitions:

Marker Molecules

Substances used to identify or track cells, biological processes, or molecules in research and diagnostic applications.

Receptor Proteins

Proteins located on the surface of cells or within cells that bind to specific molecules, triggering a response within the cell.

Ligand

A molecule that binds to another (usually larger) molecule, used especially in reference to molecules that bind to receptor sites on target cells.

G-Protein Complex

A signaling molecule that is activated by cell surface receptors and helps transmit signals from various stimuli into a cell's interior.