Characteristics of Living Things 1 Living things are

Characteristics of Living Things

1. Living things are made up of cells • Unicellular organisms – single-celled organisms • Multicellular organisms – organisms with many cells

2. Living things exhibit organization • Multicellular organisms exhibit more complexity than unicellular organisms • Unicellular organisms also have specific structures that perform specific functions

3. Living things respond to their environment • Irritability – ability of organisms to respond to a stimulus in the environment • Stimulus – any change in the environment that may cause response • Response – the reaction of an organism or any of its parts to a stimulus

4. Living things adapt to their environment • An organism must be able to adjust to environmental changes in order to survive • Camouflage is an example of adaptation

5. Living things grow and develop • Growth is an increase in size due to an increase in the number of cells • Development is accompanied by change in shape or form

6. Living things need energy • Plants use the sun’s energy to manufacture their own food through the process of photosynthesis • Animals obtain energy from plants • Chemical energy from food is transformed to mechanical energy when animals perform their functions • Heat is released in the process

7. Living things reproduce • Reproduction is the process by which organisms produce offspring or duplicate themselves • Extinction occurs if reproduction does not take place