Multiple choice

If a frog's tadpole produces too much thyroxin, _____.

  1. metamorphosis occurs earlier

  2. metamorphosis is late

  3. metamorphosis will never take place

  4. it dies

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Thyroxine controls metamorphosis timing in frogs. Excess thyroxine accelerates development, causing earlier metamorphosis. Too little thyroxine delays or prevents metamorphosis. This is a key example of hormonal timing control.