Class 11 Zoology simulations · Chemical Coordination and Integration

Thyroid feedback and iodine

Reduce dietary iodine. Less thyroid hormone is made, TSH rises by negative feedback and the thyroid enlarges (goitre).

Open the simulation

What to notice

Iodine deficiency causes hypothyroidism and enlargement of the thyroid gland (goitre).

Key relation

Hypothalamus (TRH) → pituitary (TSH) → thyroid (T₃, T₄) ⟲ negative feedback

Try this

Lower iodine intake below 50 μg/day. What happens to TSH and gland size?

What you can change

• Iodine intake: 10 to 300 μg/day

More in Chemical Coordination and Integration

• Map of endocrine glands
• Insulin, glucagon and blood glucose

See all Class 11 Zoology simulations or every Physica simulation.