Which Statement Is NOT True About the Thyroid Gland

question 19

Multiple Choice

Which statement is NOT true about the thyroid gland?

• A) It measures approximately 4 to 6 cm in length, 2 to 3 cm in anteroposterior (AP) diameter, and 1.5 to 2 cm in width.
• B) In cross-section, it is outlined anteriorly by the longus colli muscle and the internal jugular vein.
• C) The isthmus measures approximately 2 to 6 mm in AP diameter.
• D) It plays a major role in growth and development and regulates basal metabolism through the synthesis, storage, and secretion of thyroid hormones.

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Definitions:

Sexual Isolation

A mechanism of evolutionary divergence where different species or populations can no longer interbreed due to behavioral or genetic barriers.

Gametic Isolation

A prezygotic barrier where gametes (egg and sperm) of different species are incompatible, preventing fertilization.

Mechanical Isolation

A form of reproductive barrier where differences in the size and shape of reproductive organs prevent mating between species.

Sympatric Speciation

The evolution of a new species within the same geographic region as the parental species. Compare with allopatric speciation.