1. How do we define life?

2. Properties of Living Things Are organized, and are made of one or more cells (Cellular Organization) Maintain stable internal conditions (Homeostasis) Are capable of Reproduction Exhibit Growth and development Respond to their environment (Responsiveness)

3. Properties of living things (continued) Pass traits to offspring (Heredity) Use energy. Metabolism is the sum of all chemical reactions carried out in an organism.

4. Stimulus or response? The bell rings at the end of a class period Your dog runs into the kitchen when you open a can A paramecium backs up and moves away when it encounters an obstacle. A plant grows toward the window A baby hears a loud noise You pull your hand away after touching the hot oven

5. Examples Hummingbirds feed almost constantly to supply energy to their racing wings and hearts. Metabolism, homeostasis

6. A butterfly emerges from a cocoon. Growth and Development

7. A bacterium divides into new cells every 15 minutes Reproduction

8. An elephant's large ears allow the blood in the ears to be cooled by as much as 10 degrees. Homeostasis, responsiveness

9. A pill bug rolls into a ball when touched. Responsiveness

10. Earthworms are made of specialized cells, such as digestive cells, muscle cells, skin cells, etc. Cellular Organization

11. A female frog lays many eggs at a time Reproduction

12. A toad burrows in the mud during hot weather to avoid water loss Homeostasis Responsiveness

13. An amoeba is composed of a single cell Cellular Organization

14. A child inherits cystic fibrosis from her parents Heredity

15. Mitochondria in a cell release energy from sugars Metabolism, cellular organization, homeostasis

16. Branches of Biology Biochemistry: chemistry of life Ecology: how organisms interact with each other and their environment Cell biology: life on the cellular level Genetics: how organisms pass traits to their offspring

17. Evolution: changes in organisms over time Microbiology: microscopic organisms Botany: plants Zoology: animals