1. What Is Life?
5.1

2. What Are the Characteristics of All Living Things?
1. Cellular Organization: Organisms can either be composed of only one cell or many cells.
Unicellular- single celled organisms (bacteria)
Multicellular- many celled organisms – the cells become specialized to carry out certain functions.

3. 2. The Chemicals of Life:
Water- most abundant
Carbohydrates- main energy source
Proteins and Lipids- building materials
Nucleic Acid- are the genetic material (carry the chemical instructions that cells need to carry out the functions of life

4. 3. Energy Use
Organisms get energy from taking in and breaking down materials. The combination of chemical reactions through which an organism builds up or breaks down materials is called METABOLISM.
Cells use energy to grow and repair.

5. 4. Response to Surrounding:
All an organisms react to changes in their environment.
Stimulus- change in an organism’s surroundings that caused the organism to react
Response- an action or a change in behavior
Ex: You knock over a glass of water causing you to jump.
Stimulus?
Response?

6. 5. Growth and Development All living things grow and develop
5. Growth and Development All living things grow and develop. *Development is the process of change that occurs during an organism’s life, producing a more complex organism.

7. 6. Reproduction
Organisms reproduce in different ways.
- Asexual reproduction- involves only one parent and produces offspring that are identical to the parent
-Sexual reproduction- involves two parents and combines their genetic material to produce a new organism that is different from both parents.

8. Let’s Discuss…
A bird sitting in a tree flies away as you walk by. Which of the life characteristics explains the bird’s behavior?
Response to surroundings
Trees do not move like birds do, but they are living things. Why?
They have all of the characteristics of life. Movement is NOT a characteristic of life.

9. What Do Living Things Need to Survive?
Food
Autotrophs ????
Heterotrophs ????
Water
Living Space
Stable Internal Conditions
Homeostasis- maintenance of stable internal conditions

10. Let’s Discuss…
Which basic need is a fox meeting by feeding on berries?
Getting energy by eating food
The arctic fox has thick, dense fur in the winter and much shorter fur in the summer. How does this help the fox maintain homeostasis?
It helps the fox keep its internal body temperature stable even though the temperature of the fox’s surroundings change.