Thyroxine Is a Peptide Hormone,but Its Mechanism Is Different from Other

question 106

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

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Definitions:

Short Run

An interval in economic studies where a minimum of one production element remains constant and is unalterable.

Variable Costs

Expenses that change in proportion to the activity of a business.

Short Run

A time period in economics during which at least one input, such as plant size, is fixed and cannot be altered.

Profit Maximization

The procedure through which a business identifies the pricing and production volume that yields the highest earnings.