Which of the Following Molecular Mechanisms Is NOT Used in the Cell

question 52

Multiple Choice

Which of the following molecular mechanisms is NOT used in the cell in order to produce abrupt responses to a signal?

• A) Activation of a protein only when bound to multiple molecules of an activating ligand
• B) Activation of a protein only when it is phosphorylated at multiple sites
• C) Activation of a protein by simultaneously activating its activator(s) and inactivating its inhibitors
• D) A positive feedback loop in which an activated protein positively regulates its activator
• E) A negative feedback loop in which an activated protein inhibits its activator without delay

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Definitions:

Neutrophils

A type of white blood cell that plays a crucial role in defending the body against infection.

Oxygen Saturation

The percentage of hemoglobin binding sites in the bloodstream occupied by oxygen, a critical measure of respiratory efficiency.

Thorax Expands

The increase in chest volume during inhalation, facilitated by the muscles of respiration, allowing air to enter the lungs.

Trachea

The windpipe, a large membranous tube with cartilage rings that conveys inhaled air from the larynx to the bronchi.