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.⏎
Cytokine - A type of protein secreted by cells in the immune system that carries signals that facilitate cell-to-cell communication and help regulate the way the immune system responds to inflammation and infection.⏎
Ecosystem - A functional unit that consists of all the living organisms in a particular area, as well as the nonliving, physical components in the environment—such as air, soil, water, and sunlight—with which the organisms interact, and how natural and human-made changes affect these interactions.⏎
Genetics - A branch of biology that studies heredity and variation in organisms.⏎