Thyroxine Is a Peptide Hormone, but Its Mechanism Is Different

question 103

Multiple Choice

Thyroxine is a peptide hormone, but its mechanism is different from other peptide hormones. Which of the following statements is true concerning this difference?

• A) It is a stimulant of cellular metabolism and targets all cells.
• B) It does not require a second messenger to cause a response.
• C) It causes positive feedback.
• D) It is very specific in the cell type it targets.

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Definitions:

FMVSS 121

Federal Motor Vehicle Safety Standard 121, which specifies the requirements for air brake systems in heavy vehicles, ensuring safety and reliability.

Maximum Stopping Distance

The furthest distance a vehicle can travel from the point where brakes are fully applied to when it comes to a complete stop.

Mph

Miles per hour, a unit of speed indicating the number of miles covered in one hour.

Dual Circuit Foot Valve

A type of valve used in air brake systems, allowing for control of two separate circuits with one pedal.