What defines Life?

The Study of Life 1. Living things are made of one or more cells.  Cells are the basic unit of structure and function in all living things.  Unicellular  Multicellular 1.1 Introduction to Biology Chapter 1

2. Displays Organization Atoms molecules Cells Tissues Organs Organ systems Living organism The Study of Life 1.1 Introduction to Biology Chapter 1

3. Grow and Develop The Study of Life 1.1 Introduction to Biology Chapter 1 Cell division - the orderly formation of new cells. Cell enlargement - the increase in size of a cell. Cells grow to a certain size and then divide. An organism gets larger as the number of its cells increases.

4. Reproduces The Study of Life  A species is a group of organisms that can breed with one another and produce fertile offspring. 1.1 Introduction to Biology Chapter 1 Reproduction is not essential for the survival of individual organisms, but must occur for a species to survive. All living things reproduce in one of the following ways: Asexual reproduction Sexual reproduction

5. Responds to Stimuli The Study of Life Venus flytrap 1.1 Introduction to Biology Chapter 1 Living things will make changes in response to a stimulus in their environment. A behavior is a complex set of responses.

6. Living things require energy Living things take in energy and use it for maintenance and growth and to maintain homeostasis (the tendency of a cell or organism to maintain its internal environment)

7. Adapt to their environment Adaptations are traits giving an organism an advantage in a certain environment. Variation of individuals is important for a healthy species.