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.
Family: Iguanidae. Genus/species: Iguana iguana. Description. The green iguana can weigh up to 18 pounds (8 kg) and can reach a length of five to seven feet (1.5 to 2 m).This iguana has a long body covered with soft leathery scales, a long tail and short legs. Its hard, long tail is used as a weapon and for balance when climbing.he juvenile is bright green and vulnerable to predators. The iguana may be sexually mature at 16 months of age and at least nine inches (23 cm) snout-vent length. Life Span. With proper care a captive iguana can live for 20 years.