1. Characteristics of Life
Unit 2 - Biodiversity

2. It’s Alive! 1. Are made up of units called cells
2. Obtain and use materials and energy (Metabolism)
3. Grow and develop
4. Reproduce
5. Are based on a universal genetic code
6. Respond to their environment
7. Change over time.
8. Maintain a constant environment.

3. 1. Are made up of units called cells
Unicellular Organisms
Living Organism Made Up Of One Cell
Multicellular Organisms
Living Organism Made Up Of Many, Specialized Cells

4. 2. Obtain and use materials and energy
Metabolism: the way in which an organism breaks down and uses it’s energy.
Autotrophs can make their own food (some use the sun, some use chemicals).
Heterotrophs can NOT make their own food. They must consume other organisms
Herbivores eat plants
Carnivores eat meat
Omnivores eat plants & animals
Detritivores eat dead decaying matter
Decomposer break down dead decaying matter

5. 3. Grow and develop
Organisms grow by producing MORE CELLS (mitosis) & by cell ENLARGEMENT
Organisms develop as they mature into an adult organism

6. 4. Reproduce Sexual Reproduction Involves 2 parents
Egg fertilized by sperm to make a ZYGOTE
Offspring DIFFERENT from parents
Asexual Reproduction
Involves a single organism or cell
Cell divides
Offspring IDENTICAL to parent

7. 5. Are based on a universal genetic code
DNA (deoxyribonucleic acid) carries the genetic code for all organisms
All organisms contain DNA
DNA codes for the proteins that make up cells & do all the work

8. 6. Respond to their environment
Organisms Respond to stimuli (Temperature, Water, Food Supplies, etc.) In Order To Survive & Reproduce

9. 7. Change over time
Groups Of Organisms (Not Individuals) Change Over Time (evolution) In Order To Survive Within Changing Environments.
Fossil records show changes in groups of organisms

10. 8. Maintain a constant environment.
Keeping The Internal Environment (Homeostasis) Of The Cell or Organism Within The Ranges Required For Life
Stable internal conditions of pH, temperature, water balance, etc.

11. Life is organized on several levels:
Atoms
Molecules
Organelles
Cells  life starts here
Tissues
Organs
System
Organism  Kingdoms start here
Population
Community
Ecosystem
Biosphere