Question

When secretory activity in the thyroid gland increases 

A. The gland takes up iodide from the blood at a faster rate. 

B. Its follicles enlarge and fill with colloid. 

C. The follicular cells become more columnar. 

D. The follicular cells ingest colloid by endocytosis. 

E. The blood level of thyrotropin (TSH) increases.

Answer 1

A. True Iodide uptake is an index of activity. 

B. False The follicles shrink as the colloid content falls. 

C. True They change from cuboidal to columnar as their activity increases. 

D. True Reabsorption lacunae form as thyroglobulin is broken down to release hormones. 

E. False Negative feedback causes TSH levels to fall.