1. CHAPTER 7: THE BASIS OF LIFE
Unit C: Biology – Science 10

2. Section 7.1 – Life From Life
Chapter 7

3. Introduction to Cells

4. Characteristics All living things share 5 characteristics: Need energy
Produce wastes
Respond and adapt to their environment
Reproduce
Grow

5. Bill Nye Spontaneous Generation
TED Talk and Cell Theory

6. Where does life come from?
Aristotle
Observed that some organisms reproduce asexually and others sexually
Couldn’t observe any reproductive processes in small organisms
He thought that some life forms could arise from non- living matter (spontaneous generation or abiogenesis)

7. Francesco Redi ( )
First person to test the theory of spontaneous generation
Did not believe that maggots arose from rotting meat
Hypothesized that the maggots hatched from eggs dropped from flies that landed on the meat

9. Redi’s Experiment Placed meat into two glass jars
Covered one jar with a cloth that let air in and out but kept out flies and left the other jar open
A few days later he observed that there were maggots in the open jar but not in the covered jar
Was the first to give evidentiary support that spontaneous generation did not occur
Figure 7.2, page 259

10. Louis Pasteur ( )
Believed in biogenesis – life comes from life
Designed a glass flask with a S-shaped neck
Put a nutrient rich broth inside and boiled it to kill any microbes
Let sit for several days and noticed that the broth remained clear indicating that no micro-organisms entered the flask

12. Cell Theory Robert Hooke (1635-1703)
Looked at thin slices of cork from the bark of a tree under a compound light microscope
Observed many little “rooms”
He named the structures cells because they looked like monk’s small rooms in a monastery

13. Antony van Leeuwenhoek (1632-1723)
First person to describe single-celled micro-organisms
Studied blood cells, pond-water organisms, matter scraped from his teeth
Made microscopes much more powerful than those Hooke used

14. Matthias Jakob Schleiden (1804-1881) and Theodor Schwann (1810-1882)
Compared their findings and came to the same conclusion that ALL organisms contain cells
observed nuclei in all cells and concluded that each new cell came from the nucleus

15. Cell Theory All organisms are composed of one or more cells.
The cell is the smallest functional unit of life.
All cells are produced from other cells.