Nine Properties Of Life Chapter 1 Summary

Chapter 1 highlights nine properties of life. A brief description of order, metabolism, motility, responsiveness, reproduction, development, heredity, evolution, and adaptation will be provided. Also addressed, is how things like a virus, prion, and viroid, can produce, but are not considered to be alive. First is order. Order or structural and behavioral complexity lies in specific relationship to all other structures and activities. It is the precise arrangement of things structured together. Second is metabolism. Metabolism is the break down and building up of molecules in order to make energy available for needed functions. Third is motility. Motility is the ability of an organism to self-move under its own power. Fourth is Responsiveness. Responsiveness is the organism’s ability to react to its environment and surroundings. Fifth is reproduction. Reproduction is an organisms ability to create a like organism.
Development is the sixth property of life. Development is the ability of an organism to increase in size or mass as it develops. Heredity is the seventh property of life. Heredity is an organism’s ability to pass along gene traits from the parent organism. Eighth is evolution. Evolution is when an organism changes and adapts to an environment to ensure survival. The ninth and final property of life is adaptation. Adaptation is when an organism develops its structure, behavior and abilities to survive in their environment. How does a virus, prion, and viroid produce and not be considered alive?
Viruses, prions, and viroid do not meet the characteristics of the property of life. They attach themselves to a cell and uses the cells processes in order to replicate. When deoxyribonucleic acid (DNA) from the virus is infused into a healthy cell, the cell incorporates the virus’s DNA. “Once the virus’s membrane has fused with the cell membrane, the virus releases its genetic material which gets copied into the cells own genetic language, and this new language enters the cells repository of genetic information” (Postlethwait and Hopson, 2011). The virus uses the cell as a carrier in order to reproduce. The cell adapts it structure to survive in its environment. Viruses, prion, and viroids are simply parasitic mutations uses the host cells’ functions in order to recreate itself. The cell meets the nine properties of life and the virus uses the cells life function in order to replicate. Without the cell a virus cannot survive. Therefore, a virus cannot be considered
alive.

References
Posthletwait, J and Hopson, J (2011) Life (2010-2011 Edition). Belmont, CA: Brooks/Cole, Cengage Learning.