This Structure of the Extensor Mechanism Lies Volar to the Axis

question 27

Multiple Choice

This structure of the extensor mechanism lies volar to the axis of the proximal interphalangeal (PIP) and dorsal to the axis of the PIP.

• A) Flexor digitorum profundus (FDP)
• B) Lumbricles
• C) Oblique retinacular ligament (ORL)
• D) Transverse retinacular ligament

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Definitions:

Potassium Channels

Pores in cell membranes that allow potassium ions to pass through, regulating cell function.

Sodium Channels

Protein-based channels found in cell membranes that allow sodium ions to flow in and out, critical for generating and transmitting electrical signals.

Membrane Potential

The electrical potential difference across a cell's plasma membrane, crucial for the conduction of impulses in muscle and nerve cells.

Channels

Structures that form pores in the membranes of cells and organelles, allowing the selective passage of ions or molecules across the membrane and thus contributing to vital physiological processes.