1. The 8 Characteristics of LIFE!!
Pennington
Biology
2010

2. Criteria:
To be considered “living”, an object must possess the eight characteristics described throughout this presentation.
Some things possess some of the eight, but not all. They are therefore non-living, like a virus.

3. 1. DNA
All living things contain genetic material called DNA (deoxyribo nucleic acid).
DNA is a double helix structure:

4. 1. Continued:
Genetic traits (like hair and eye color) are passed from parent to offspring via DNA.

5. 2. All Living Things Are Made of Cells
Cells can make two different levels of organisms: single celled or multicellular

6. 2. Cells – Continued:
1) Unicellular – like bacteria or the protist below (an amoeba)

7. 2. Continued:
2) Cells can also divide and create multicellular organisms, like all plants, animals and fungi:

8. 3. All Living Things Must Obtain and Use Energy
The Sun provides energy to producers, who use it to photosynthesize their own sugars:( autotrophs)

9. 3. Continued
Consumers eat producers thereby transferring the energy into the new system: (heterotrophs)

10. 3. Continued
Decomposers break down organic molecules to obtain their energy and some return it back to nature!

11. 4. Reproduction
All living things have the ability to reproduce. This can happen in two ways:
1) Sexual reproduction – 2 partners, each donating 50% of their genetic code.

12. 4. Continued:
2) Asexually – 1 organism divides into 2 cells that are 100% genetically identical.

13. 5. Grow and Develop
All living things must grow and develop into the adult/reproductive stage of life.
The rose below began as a bud and two days later grew into the full rose:

14. 6. Respond to the Environment:
Organisms live in constantly changing ecosystems, therefore they must be able to respond to stimuli in the environment. (Ex. Light, sound, touch)
Ex: Sunflowers follow the sun across the sky to continually capture its light energy. Below is a sunflower at 9:00 a.m. pointing towards the Eastern sky, to the right is the same flower at 4:00 p.m. directed at the Western sky.

15. 7. Homeostasis
Living things must keep their internal environments relatively stable.
Ex: A dog pants to release internal heat to maintain constant body temperature:

16. 8. Evolution
As a group, organisms must adapt over time to ever changing conditions
Ex: Conifers have developed small, needle shaped leaves to avoid losing hard to come by water...