2. The Science of Life Mrs. Franchok
Chapter 1
The Science of Life
Mrs. Franchok

3. The Characteristics of Life
History:
Spontaneous Generation or Abiogenesis-
1st proposed by Aristotle
held that complex, living organisms are generated by decaying organic substances,
e.g. that mice spontaneously appear in stored grain or maggots spontaneously appear in meat.

4. The Characteristics of Life
History:
Was widely believed until the 19th century.
Several scientists performed experiments that disproved spontaneous generation
Francisco Redi
Lazzaro Spallanzani
Louis Pasteur

5. Redi’s Experiment
Francisco Redi
1668

6. Spallanzani’s Experiment
Lazzaro Spallanzani
1746

7. Pasteur’s Experiment
Louis Pasteur
1859

8. The Characteristics of Life
History:
Biogenesis- is the process of life forms producing other life forms
e.g. a spider lays eggs, which form into spiders.
The term is also used for the assertion that life can only be passed on by living things.

9. The Characteristics of Life
How can you tell if something is alive?

10. What is Biology? Biology is the study of Life. “Bio” - Life
“logos”- Study

11. What is Life?
There are seven characteristics used to define life: I ORDER A
1. Information
2. Organization
3. Respond
4. Develop
5. Energy
6. Reproduce
7. Adapt

12. What is Life?
Organism – Any unicellular or multicellular form that possess all seven (7) characteristics of LIFE.

13. Genes - pieces of DNA that holds our personal “blueprint”.
I = Information
Living things pass on information about survival to future generations.
Genes - pieces of DNA that holds our personal “blueprint”.
Behaviors are learned/instincts – ex. Imprinting, Habituation

14. Living things are highly ordered.
O = Organization
Living things are highly ordered.
A. Group – everything we do affects other things.
Ex. Food chains, energy chains, competition
Extinct = “die out”
B. Made of cells
Individual – Unicellular = One (1) cell
Multicellular = more than One (1) cell

18. R = Respond
Living things Respond to the environment (hibernate, roll, play dead, and grow toward light).
Often the Response involves movement.
Stimulus – event that causes a response (Fear, light, lack of food).
Homeostasis – need to maintain a stable, internal, environment. (VITAL Response)

19. D = Develop
Living things Develop – move from stage to ordered stage until they reach a mature form. (Metamorphosis, Embryo)
Growth – increase in mass by changing raw materials into living material. Increase in your cells(height)
Develop – rapidly or slowly occurring changes. (learning to add/multiply)

21. E = Energy Living things require Energy.
Metabolism – all the chemical activities carried out by living things.

22. How do Organisms get Energy?
Autotrophs – make their own food.
Heterotrophs – can not make their food; they depend on autotrophs and other heterotrophs for their food.
AUTOTROPH HETEROTROPH

23. How do heterotrophs convert food into useful Energy for the body?
Digestion – breakdown of food
Respiration – food is oxidized to make sugars
Synthesis – sugars provide energy for body to make living material.

24. R = Reproduce
Living things Reproduce – important to species, not the individual.
Asexual – One (1) parent clones
Sexual – Two (2) parents, each donate sex cells to create unique individual

25. A = Adaptation
Living things Adapt – respond over several generations to environmental pressure (Bacteria resistant to antibiotic, Pest resistant to pesticide)
Adaptation – Structure, behavior, or internal change that helps an organism survive (fulfill its life span)

26. The Characteristics of Life
Are bacteria alive?
How about viruses?