The distinctive structure of a jet uses principles of physics to enable it to take off and remain airborne. Its form is directly connected to its function. Living things have this characteristic, too. For example, because cats are nocturnal predators, their eyes have many rods, which are light receptors. The relationship between structure and function is one of the major themes of biology and is seen throughout the natural world.
Same, Yet Different
Within organisms, form and function go hand in hand. This is especially noticeable when two structures appear very similar. Their small differences have specific purposes. For example, a bird feather is composed of numerous small vanes attached to a shaft. These multiple sections combine with the layered arrangement of the feathers and provide excellent insulation for birds. However, in birds like peacocks, some feathers are brightly colored. The purpose of these feathers is to attract a mate.
This Leads to That
Understanding the structure of a biological component provides insight into its function. For instance, researchers at the University of Michigan and Purdue University have investigated how the viruses that cause West Nile fever and dengue fever reproduce. Their goal is to develop vaccines or medications for treatment. By discovering the structure of a protein, they have begun to understand the viruses’ replicating processes, as well as how the viruses affect the immune system.
Understanding function provides insight into structures. For example, the human digestive system has two purposes: using food to derive energy to carry out life processes and removing wastes. These are complex procedures that require multiple structures to perform different but related jobs. Digestion begins in the mouth as chewing reduces food to smaller bits and saliva introduces digestive enzymes. Many body parts participate until the process is complete, including the esophagus, stomach, small intestine, pancreas, liver, gall bladder, colon, rectum and anus.
Size Doesn't Matter
The relationship between form and function occurs at various stages of an organism’s organization. At the cellular level, a neuron, or nerve cell, has protrusions from its main body. These dendrites and axons allow nerve signals to pass between cells. On a larger scale, the structure of a bird's wings contributes to its ability to fly. A bird’s ulna, or “arm” bone, is hollow inside. This reduces the overall weight of the skeleton.
- Popular Science: See the World Through the Eyes of a Cat
- Collin County Community College District: Introduction -- Themes in the Study of Life
- Cornell Laboratory of Ornithology: All About Birds -- Feather Structure
- Biology: Understanding Life
- Animal Planet: Birds: Peacock
- Futurity: Health and Medicine -- "Two-Faced" Protein Holds Clues to West Nile
- Cleveland Clinic: Diseases & Conditions
- Littleton Public Schools: Littleton High School -- Form and Function
- Mississippi College: Introduction -- Themes in the Study of Life
- Henderson State University: Skeletal Adaptations of Birds for Flight
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