1. Characteristics of Life

2. So, what is ALIVE?

3. 6 Characteristics There are certain characteristics that all forms of life share. To be classified as “LIVING” the following must be present: Organized Grow and develop Reproduce Respond to a stimulus Maintain certain internal conditions Energy

4. Only those things that have all 6 characteristics of life are living. Things that have all characteristics of life are called ORGANISMS

5. Living Things are Organized Whether an organism is made of one cell or many cells, all living thing have structures that have specific functions Some living things contain only a single cell –These single-celled organisms are called UNICELLULAR –They perform all the functions necessary for life Most living things are MULTICELLULAR –They contain two or more cells. Some have hundreds, thousands, or even trillions of cells. Humans have approximately 6 trillion cells.

6. Living Things Grow and Develop Increase in size Development LIFE SPAN: the maximum length of time a particular organism can be expected to live.

7. Living Things Reproduce The process by which living things make more of the same type of living thing: Sexual Reproduction/two parents Asexual Reproduction/one parent

8. Living Things Respond to Their Environment Stimuli=any change in the environment of an organism that produces a response by that organism. –Internal: hungry, thirsty –External: light, temperature Response= an action, movement, or change in behavior of the organism.

9. Homeostasis maintain certain internal conditions Homeostasis: an organism’s ability to maintain steady internal conditions when outside conditions change. –It ensures that cells can function, otherwise they may die. Methods of homeostasis –There is a limit to the amount of change that can occur within an organism

10. Living Things Use Energy The cells of organisms use energy to do what living things must do.

11. Energy is used when… Metabolism=the sum total of all the chemical reactions that occur in a living thing Ingestion=take in/or produce their food Digestion=the process by which food is broken down into simpler substances Respiration=the process by which living things take in oxygen and use it to produce energy Excretion=the process of getting rid of waste material

12. Homework Read pages 9-15 Copy the table 1 page 15 into NB by hand. You may draw or cut out pictures. You may also use the computer to type table out and cut & paste pictures YOU MAY NOT JUST PHOTO COPY THE PAGE!!