Final answer:
Rickets is caused by a deficiency in vitamin D, not an insufficient amount of melanin, leading to soft, weak bones and skeletal deformities in children.
Step-by-step explanation:
The statement that the bone disorder rickets is caused by an insufficient amount of melanin is false. Rickets is actually caused by a deficiency in vitamin D, which is crucial for the proper absorption of calcium and phosphates by the bones. This condition leads to softening and weakening of the bones in children, potentially resulting in deformities and fractures. Rickets can be prevented and treated by ensuring an adequate intake of vitamin D through diet, supplements, or adequate sunlight exposure, which assists the skin in synthesizing the vitamin.