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.
Iguanas are reptiles and nearly all reptiles lay eggs. There are some reptiles that do not lay eggs, but they are very rare. Female iguanas usually lay a clutch of eggs every year once they're mature. If there is no male iguana, she will still lay eggs, but they won't be fertile.
Their markings and shadings are just like other iguanas, just the colors are different. When happy/healthy, they may get some green in their stripes or markings. They essentially look like a photograph negative of a green iguana.guana Color Variants The following color variants (except the brown) are not generally seen until the iguana is heading into sexual maturity. The hatchlings' deep greens, useful in camouflaging them, begins to lighten, striping or patching diffuse or develop, as they reach one year of age.