1. Spontaneous Generation
How did life start on our wonderful Earth?
Spontaneous Generation

2. Early Earth Formation began approximately 4.6 billion years ago.
Composition of the early Earth’s atmosphere:
Water vapor
Carbon Monoxide & Carbon Dioxide
Hydrogen Sulfide
Methane
Hydrogen

3. Spontaneous Generation
The theory that living organisms can come from non-living objects.
IS NOT TRUE!!!

5. Spontaneous Generation
Disproved by 2 scientists:
Francesco Redi
Conducted an experiment to disprove spontaneous generation in large visible organisms.
Louis Pasteur
Conducted an experiment to disprove spontaneous generation on the microscopic organisms.

6. How did life originate on Earth?
We don’t know!
What we do know:
There is evidence for the creation of the building blocks of life in the harsh conditions of the Early Earth
There are locations in the Earth where these building blocks would be protected from the harsh conditions of the Early Earth
What sparked life from these building blocks?  No evidence.

7. Where did the building blocks of life come from?
2 Most common theories
Stanley Miller (Miller-Urey Experiment)
Simulated the conditions of the early Earth, which created the building blocks of life!
Comets & Meteors
Past studies have found the existence of peptides within Meteorites
More evidence may come from the recent Rosetta spacecraft and Philae lander.

8. Protected locations where life could have begun
Deep within the Earth’s crust.
Deep within the ocean, at the thermal vents.

9. Evidence of the first living organisms
Rocks 3.8 billion years old show evidence of carbon compounds that are created by cells
Stromatolites
Ancient cyanobacteria which created fossils 3.5 billions years old

10. First Cells Modern Cells 3.5 Billion Years Ago Did not require Oxygen
Consumers
Simple (unicellular)
Current
Most require Oxygen
Consumers, Producers, and Decomposers
Simple and Complex (multicellular, contains nucleus)

11. The Characteristics Common to All Living Organisms
Life

12. Needs of Living Organisms
Organization and Transport
Growth and Development
Reproduction
Response to Stimuli
Homeostasis
Use of energy

13. Organization and Transport
Organisms have specialized structures to perform specific functions
Unicellular: Made up of one cell
Are able to simply move substances into and out of the cell using diffusion
Multicellular: Made up of many cells
Same as unicellular, but also requires a circulatory system to bring substances to and away from each and every cell.

14. Growth & Development Increase in size or number of cells
Multicellular organisms have cells develop to perform specialized functions.
Some organisms go through Metamorphosis:
A process in which an animals body undergoes dramatic changes in form

15. Reproduction Producing offspring of the same species.
Internal Development
When an offspring develops in their mother (Live birth, ex… humans)
External Development
When an offspring develops outside their parents body (Eggs laying organisms, ex… birds)

16. Reproduction Sexual Reproduction Asexual Reproduction 2 Parents
2 Types
Sexual Reproduction
Asexual Reproduction
2 Parents
Offspring are not identical to parents
1 Parent
Offspring are identical to parent

17. Asexual Reproduction Budding Binary Fission
When an organism grows off the parent
Example:
Hydra
When one cell splits in half into 2 cells.
Example:
Bacteria

18. Asexual Reproduction
Budding
Binary Fission

19. Response to Stimuli
To survive organisms must be able to respond to stimuli.
More complex (multicellular) organisms have a nervous system to respond to stimuli.
Nervous System:
Stimuli are converted to messages in the form of (electrical) impulses that are sent through neurons to the central nervous system.
Neurons are used to send messages of stimuli and messages to muscles cells to respond

20. Response to Stimuli cont…
Endocrine System:
Uses hormones (chemicals) to transfer messages throughout the human body.

21. Homeostasis & Regulation
A constant internal environment
Examples:
Warm blooded animals create their own heat to regulate their body temperature
Cold blooded change their behavior to bask in the sun to regulate their body temperature

22. Use of Energy Respiration: Release of chemical energy
Occurs in each and every cell of your body
How do organisms obtain chemical energy?

23. Heterotrophs Autotrophs Chemotrophs
Organisms that must obtain their source of energy by consuming (eating) other organisms are known as..
Heterotrophs
Organisms that obtain energy of the sun and use it to create food are…
Autotrophs
Organisms that obtain energy from chemicals found in extreme environments are known as…
Chemotrophs

25. The molecules that make of all living things
The chemistry of living things
The molecules that make of all living things

26. What are organisms made of?
Carbohydrates
Proteins
Fats/Oils
Nucleic Acids
Water

27. Carbohydrates Made of C,H,O Main source of energy for living things
Used to provide structural support
The walls of plants are made of starch, a large carbohydrate.

28. Proteins
Made of C,H,O,N
are long changes of Amino Acids (the building blocks of a protein).
Used as an energy source
Used for structure:
to build hair, muscles, and other body parts
Used for cell communication
Hormones are made of proteins and are used to communicate information to different body structures.
Used to speed up chemical reactions
Enzymes are proteins that help the body speed up reactions (such as breaking down food)

29. Lipids (Fats/Oils) Made of C,H,O Used as an energy source
Used for long term energy storage
Provides cushioning and insulation
Used as a protective barrier
Lipids do not mix with water, acting as a barrier to water soluble substances.

30. Nucleic Acids “Blueprints of life”
Store the instructions for all processes within a living organism
Example: Cell growth, reproduction, etc…
Examples:
DNA (deoxyribonucleic acid)
RNA (Ribonucleic acid)

31. Water O H H Helps dissolve (break down) food
Transports heat, food, and waste
Helps maintain a constant body temperature
Drink more water!! (and less sugary drinks) H O H