2. The Characteristics of Living Things  Biologists use six characteristics to classify something as a living thing. 1. Have a cellular organization 2. Use and Need Energy 3. Contain similar chemicals 4. Respond to Surroundings 5. Reproduce 6. Grow and Develop

3. The Characteristics of Living Things §All living things have these six characteristics. §Anything without one of these six characteristics is nonliving. §Living things are called organisms.

4. 1. Cellular Organization §Organisms are made up of one or more cells. §A cell is the basic unit of structure and function in living things. l Cells = the of life.

5. §Single celled organisms are called unicellular §Many celled organisms are called multicellular §Cells in unicellular organisms do many tasks while those in multicellular organisms are specialized for one task

6. 2. Use and Need Energy §All organisms need and use energy to live. §Energy is the ability to do work.  Sunlight is the source of energy for most living things. l Plants use the energy in sunlight to make food, and animals get energy by eating plants or other animals that have eaten plants.

7. §All the chemical reactions that occur in a cell are called the cell’s metabolism.

8. 3. Respond to Their Su rroundings §Organisms that are living respond to changes in their environment. §Any change in environment ( a sound, a change in temperature, light etc.) that causes an organism to react is a stimulus.

9. §An organism reacts to a stimulus with a response. §For example, when the environment temperature increases, humans will sweat. When a loud sound occurs, we startle.

10. 4. Are made of the chemicals of life §The most abundant chemical in living things is water §The main energy source is carbohydrates (sugars)  Any reaction to change is called a response. l For example: A bright light may cause you to blink.

11. §Living cells are made of proteins, and lipids. §The genetic material in all living things that carries the instructions cells need to live is called DNA (deoxyribonucleic acid). It is made of nucleic acids.

12. 5. Reproduce §Organisms produce more organisms of their own kind. §Reproduction allows organisms to continue living on the earth.

13. §There are two types of reproduction: §Asexual reproduction: involves only one parent, offspring are exactly the same as the parent. §Sexual reproduction: involves 2 parents, combines their genetic material (DNA) to produce offspring that are different from both parents.

14. 6. Grow and Develop  Living things change, or develop, during their lifetimes. l One way organisms change is by growing (becoming larger). Living things may also change in appearance during stages in their life. This is development. For example: tadpoles and frogs §All organisms grow and develop.

15. Summary §Biologists use six characteristics to classify something as a living thing. 1. Have a cellular organization 2. Use and Need Energy 3. Contain similar chemicals 4. Respond to Surroundings 5. Reproduce 6. Grow and Develop All living things display all of the above characteristics.

16. Living Things come from other living things through reproducton §Hundreds of years ago people believed in spontaneous generation: that living things can come from nonliving things. §This was disproven by Francisco Redi in the 1600’s. §http://www.bing.com/videos/search?q=video+%2b+what+is+spontaneous+generati on&view=detail&mid=AB6781F0040789767B89AB6781F0040789767B89&first=0 &qpvt=video+%2b+what+is+spontaneous+generationhttp://www.bing.com/videos/search?q=video+%2b+what+is+spontaneous+generati on&view=detail&mid=AB6781F0040789767B89AB6781F0040789767B89&first=0 &qpvt=video+%2b+what+is+spontaneous+generation

18. Louis Pasteur- 1800’s §Finally totally disproved spontaneous generation §http://www.youtube.com/watch?v=j6CTloy TsAohttp://www.youtube.com/watch?v=j6CTloy TsAo

20. All Organisms have the same basic needs. The Needs of Living Things

21. §Four Basic Needs: §Food §Water §Living Space §Stable Internal Conditions

22. 1.All living things need a source of Energy (FOOD)to carry on life processes. Organisms are grouped by how they get their food for energy. Autotrophs: (self-feeder) organisms that make their own food through the process of photosynthesis: plants,some bacteria, protists Heterotrophs: must feed on other organisms(animals, fungi)

23. §The ultimate energy source for all organisms is the SUN!

24. a. Most chemical reactions involved in metabolism require water. b. Obtained from fluids and food. Water makes up 90% of human blood. Humans can only live 3 days without water. 2. All living things need WATER.

25. 4. All living things need a LIVING SPACE. a.All organisms need a place to live which contains the things they need to survive. b.Organisms have a habitat and niche within their living Space

26. §Habitat: the place where an organism lives  Niche: An organism's way of life and its relationship to the living and nonliving things in its environment.

27. 4. Stable Internal Conditions §Organisms must keep the conditions inside their body stable, even if conditions in the environment change. §Homeostasis: the maintenance of stable internal conditions. §Examples: thirst after a workout § sweating to keep body temperature stable