Gene - The physical and functional unit of heredity made up of DNA. Every individual has two copies of each gene, one inherited from the mother and the other from the father.⏎
Exoskeleton - An external skeleton that protects and supports an organism, in contrast to an internal endoskeleton.⏎
Disease - Any abnormal condition that affects all or part of an organism, resulting in symptoms such as pain or loss of function.⏎
Gastrointestinal Tract - The structure in the body, beginning with the mouth and extending to the anus, through which food is ingested, broken down, and absorbed to provide the body with nutrients, and waste products are excreted.⏎