1.2: Biology Systems and Water
There are some core properties that are found in all living things. Since it is unreasonable to memorize every biological discovery, biologists focus on unifying themes that every discovery falls under. Earth, the only known biosphere, is made of 75 to 80 percent water. Since the properties of water are conducive to life on earth, scientists search for life when they discover the presence of water on other planets.
The characteristics of living organisms (evolutionary adaptation, growth, reproduction, etc.) differentiate living and non-living things. The fundamental difference between a living thing and a dead thing is metabolism. Metabolism is the chemistry of life. It includes all of the chemical reactions occurring in all of the cells that make up an individual organism. Life ceases when the chemical reactions of metabolism cease. Read this chapter to explore and identify the common characteristics of living organisms.
These characteristics of life include adaptation, cell structure, growth and development, homeostasis, metabolism, reproduction, and responsiveness to the environment.