1. The cell is the basic unit of living things.
Cells & Heredity 1.1
The cell is the basic unit of living things.

2. I. Living things are different from nonliving things.
Characteristics of Life
Organization
Enables organism to meet its needs
Very simple (bacteria) or complex (kingfisher)
Ability to develop and grow
Ability to respond to the environment
Pupils dilate, blinking
Ability to reproduce

3. Needs of life Energy Almost all comes from the sun Food Materials
Carbon dioxide, nitrogen, oxygen, water
Living space

4. II. All living things are made of cells.
Cells are the smallest unit of living things
Unicellular
Made of a single cell
Too small to see directly

5. Multicellular Made of many cells Most of the organisms you see
Contain specialized cells that work together to carry out the basic activities of life

6. Microscopes Led to the discovery of cells
Instrument which makes an object appear bigger than it is

7. III. The microscope led to the discovery of cells.
Robert Hooke
Anton van Leeuwenhoek
1660s
Named cells (looked like tiny rooms)
Used 30x magnification
Observed bark cells – dead cells
1670s
Used 300x magnification
Observed living cells in pond water

8. IV. Cells come from other cells.
Cell Theory
Every living thing is made of one or more cells.
Cells carry out the functions needed to support life.
Cells come only from other living cells.

9. V. The cell theory is important to the study of biology.
Scientific theory
Widely accepted explanation of things observed in nature
Must be supported by evidence & observations
Louis Pasteur
Observed that spoiled milk contained bacteria
Developed pasteurization to kill bacteria in milk
Keeps milk fresher longer
Disproved spontaneous generation
The process of bacteria growing from nonliving materials

10. Pasteur’s Experiments
Pasteur’s experiments showed that bacteria are present in the air.
They do not grow spontaneously.
-- End of flask is sealed.
1. Broth is boiled to destroy any living bacteria, and the flask is sealed.
2. A few days pass, and the broth is still clear. No bacteria have grown.
3. Two to three days pass, and the broth is still clear. No bacteria have grown.
-- End of flask
is broken.
--Exposure to air is the variable.
1. Broth is boiled to destroy any living bacteria, and the flask is sealed.
2. The end of the flask is
broken to expose the broth to the air. The broth is clear.
3. Two to three days pass, and the broth is cloudy because of the growth of bacteria.