CHARACTERISTICS OF LIVING ORGANISMS Identify the 7 Characteristics Explain the meaning of each characteristic using scientific examples

1) Organization & Cells Organization: Degree of order within an organism’s internal and external structure & how it interacts with the environment. Cells: Smallest unit that can perform all life’s processes. 1. Unicellular= 1 cell (bacteria) 2. Multicellular= Multiple cells (trees, fish, you)

2) Response to Stimulus A physical or chemical change in the internal or external environment. Examples: Dilating eyes in response to change in light. Pulling hand away after touching hot stove. Sneezing in response to dust or allergies. Leaves changing colors during Fall.

3) Homeostasis Maintaining a stable internal environment even when environmental conditions change. Example: Your body temperature is maintained at approximately 98°F. When your body heats up, your sweat glands secrete water to cool your skin. When you are cold, your body constricts the skin (goosebumps) to conserve heat.

4) Metabolism Sum of all chemical reactions that involve taking in and transforming energy & materials from the environment. Purpose of metabolism is to obtain energy for repair, movement, and growth. Example: Plants, algae, and bacteria use the sun’s energy to generate sugar (food) through photosynthesis. You depend on other organisms to obtain energy.

5) Growth & Development All living things grow and increase in size by the cells dividing and enlarging.

6) Reproduction Production of new organisms. Reproduction, unlike the other 6 characteristics, is not essential to the survival of an individual organism. It is essential for the survival of the species. During reproduction, organisms pass on genetic information (DNA) to their offspring. Sexual: hereditary information is combined from 2 organisms of the same species. Asexual: hereditary information from different organisms is not combined ~ the original organism and new organism are genetically the same. Ex) bacteria

7) Change Through Time Although individual organisms experience changes during their lifetime, their basic genetic characteristics do not change. Populations of living organisms evolve or change over long periods of time in order to survive in a changing world. Example: Peppered Moth

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