Quiz Please sign up for the course before taking this quiz. 5′-deiodinase1 Breakdown of T4 into reverse T3 Conversion of TSH to TRH Conversion of T4 to T3 Conversion of T3 to T4 According to the presenter, deficiency of which nutrient can cause decreased production of T4?1 Iron Vitamin B5 Zinc Vitamin D Signs and symptoms of low thyroid production may include:1 Paresthesias Bipolar disorders Impaired kidney function All of the above