Which statement about thyroid hormones is correct?
1) Iodide in the thyroid combines with tyrosine to form T 3 and T 4.
2) Thyroid hormone increases the production of white blood corpuscles.
3) Warm temperatures affect the conversion of thyroxine (T 4) to triiodothyronine (T 3).
4) Dietary intake of carbohydrates and iodine is required to produce thyroid hormones.