What Clues Provided Evidence of the Mechanism of Channel Inactivation

question 13

Multiple Choice

What clues provided evidence of the mechanism of channel inactivation?

• A) Trypsin digestion of the cytoplasmic side caused the channel to stay open.
• B) Protein mutants have different inactivation kinetics.
• C) Inactivation could be restored by the addition of part of a missing peptide.
• D) A and B
• E) All of the answers are correct.

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Definitions:

Capillary Walls

The thin, permeable walls of capillaries, the smallest blood vessels, which allow for the exchange of oxygen, carbon dioxide, nutrients, and waste between blood and surrounding tissues.

Amphibian Heart

The amphibian heart is made up of three chambers: two atria and one ventricle, supporting a dual circulatory system that separates oxygen-rich and oxygen-poor blood.

Sinus Venosus

A structure in the heart of some vertebrates that collects oxygen-poor blood from the body to be oxygenated in the lungs or gills.

Conus Arteriosus

The tapering chamber connecting the ventricle of the heart to the aorta in some vertebrates, smoothing the blood flow as it enters systemic circulation.