3. Is It Alive?
The Seven Characteristics of Life

4. What is Biology?
Biology –

5. What is Biology?
Biology – the study of LIFE

6. What Makes Something Alive?

7. What Makes Something Alive?
Biologists have established that all living things share seven characteristics in common.
In order to be considered a “living” organism, one must show all seven characteristics.

8. 1) Organization and Cells
Organization – the high degree of order, both externally and internally, shown by living organisms.
External Organization:
vs.

9. 1) Organization and Cells
External Organization:
Externally, all wolves look essentially the same, while rocks can come in many different shapes.
vs.

10. 1) Organization and Cells
Internal Organization:
Internally, wolves (like other mammals) have organs which are organized to work together to promote the well being of the organism.
vs.

11. 1) Organization and Cells
Cell – the smallest unit that can perform all of life’s process.

12. 1) Organization and Cells
Cell – the smallest unit that can perform all of life’s process.
All living things are composed of, at least, one cell.

13. 1) Organization and Cells
Cell – the smallest unit that can perform all of life’s process.
All living things are composed of, at least, one cell.
Unicellular – an organism made up of one cell

14. 1) Organization and Cells
Cell – the smallest unit that can perform all of life’s process.
All living things are composed of, at least, one cell.
Multicellular – an organism made up of multiple cells
Unicellular – an organism made up of one cell

15. 1) Organization and Cells
A group of cells form a tissue,
A group of tissues form an organ.
A group of organs form an organism.

16. 2) Response to Stimuli
Stimulus – a physical or chemical change in an organism’s environment.
How do you respond to stimuli?

17. 2) Response to Stimuli
Stimulus – a physical or chemical change in an organism’s environment.
What happens when you shine a flashlight into your eye?

18. 3) Homeostasis
Homeostasis – the maintenance of stable internal conditions in response to environment.

19. 3) Homeostasis
Homeostasis – the maintenance of stable internal conditions in response to environment.
Homeostasis occurs to combat ever-changing external conditions.

20. 3) Homeostasis Ex: Sweating
Homeostasis – the maintenance of stable internal conditions in response to environment.
Homeostasis occurs to combat ever-changing external conditions.
Ex: Sweating
How does sweating maintain internal conditions?

21. 4) Metabolism
Living organisms use energy to power all their life processes.
Metabolism – all chemical reactions occurring to take in and transform energy within an organism.
Plants get energy from _____
Animals get energy from ___

22. 4) Metabolism
Living organisms use energy to power all their life processes.
Metabolism – all chemical reactions occurring to take in and transform energy within an organism.
Plants get energy from the sun
Animals get energy from eating

23. 5) Growth and Development
Growth – an increase in size due to the division and enlargement of cells.
Development – the process by which a young organism becomes a mature adult (capable of reproduction).

24. 6) Reproduction Reproduction – the process of creating offspring.
In order for a species to continue to exist, it must reproduce.
Sexual Reproduction requires both a male and female parent.
Asexual Reproduction requires only one parent.

25. 7) Change Through Time
Over long periods of time, populations of living organisms evolve new characteristics through the process of natural selection.
This is the hardest characteristics to observe. Why?

27. Is It Alive? - Activity
Form groups of 3 or 4 and choose one of the seven lab stations.
On your own paper, each person within the group will
Identify the object
Determine if it is “alive” or “non-living”
Write two supporting sentences backing up your claim with evidence from the lecture.

29. Exit Slip
- This organism was recently discovered on Mars. Scientists have asked you to determine if this is a living cell or a non-living object.
If this organism is alive, which two characteristics should it display? a) Response to Stimulus and Movement b) Breathing Oxygen and Change Over Time c) Reproduction and Homeostasis d) Growth and Producing Carbon Dioxide

30. Exit Slip
- This organism was recently discovered on Mars. Scientists have asked you to determine if this is a living cell or a non-living object.
2) When placed in cold water, this organism closes its pores to maintain heat. This is an example of what characteristic of living things? a) Metabolism b) Homeostasis c) Growth and Development d) Cells and Organization

31. Exit Slip
- This organism was recently discovered on Mars. Scientists have asked you to determine if this is a living cell or a non-living object.
3) Which statement would prove that this organism is NOT alive? a) this organism shows a high degree of internal organization b) this organism derives energy from sunlight through photosynthesis c) this organism reproduces asexually d) this organism does not respond to stimuli