When this happens, the thyroid gland is no longer under pituitary control. The amount of hormone it produces is dependent on levels of TSI. TSI are the direct cause of hyperthyroidism in Gravesâ disease and various immune system chemicals known as cytokines also contribute to the symptoms that occur in this disorder.
Confidence votes 20. Female Iguanas will lay eggs when they become sexually mature, which is around 1.5 to 2 years old. They do not need to be fertilized to lay so therefore do not need a male Iguana. They need to be healthy before they lay or else there can be very serious problems.
Iguanas just-out-of-the-egg are about 2.5-4.5 inches long. They grow rather slowly until they are eight or nine months old. After that, they grow much faster-if they are well cared for. By the time they are two years old, they can be 2-3 feet long. And by the time they are 3-4 yrs, they can be near their maximum size.