What is the goal of science?
To investigate and understand the natural world
To explain events in the natural world
To use those explanations to make useful predictions
What is an observation?
The process of gathering info about events or processes in a careful, orderly way
What is the structure of a controlled experiment?
Whenever possible, a hypothesis should be tested by an experiment in which only one variable is changed at a time. All other variables should be kept unchanged, or controlled
What is the responding variable?
The variable that is observed and changes in response to the manipulative variable
In Redi's experiment, what was the controlled variable?
Type of meat
What was Needham's test of Redi's findings?
He claimed that spontaneous generation was possible under the right conditions.
1. Sealed a bottle of gravy
2. Heated it
3. Said that the heat killed any life in the gravy
4. After several days, the bottle was swarming with activity
What was Spallanzani's test of Redi's findings?
He thought that Needham had not heated his samples enough
1. Boiled to containers of gravy
2. He immediately sealed one jar, and left the other open
3. After several days, the open jar was teeming with microorganisms
4. The sealed jar was free of microorganisms
What was Pasteur's test of spontaneous generation?
He designed a flask with a long, curved neck
1. The flask was open, but microorganisms ould not get in
2. He boiled the flask to kill and possible microorganisms
3. He waited a year
4. In that time, there were no microorganisms
What was the impact of Pasteur's work?
1. He saved the wine industry
2. He saved the silk industry
3. He created penicillin
What does theory apply to in science?
A well tested explanation that unifies a broad range of observations
What are the 8 characteristics of living things?
1. They are made of cells
2. They reproduce
3. They are based on DNA
4. They grow and develop
5. The obtain and use materials an energy
6. The respond to their environment
7. The maintain a stable internal environment
8. As a group, they change over time (EVOLUTION)
What are the levels of organization in order?
1. Molecules (Atom groups)
2. Cells (Smallest unit of life)
3. Groups of Cells (Tissue, Organs, Organ Systems)
4. Organism (Individual living thing)
5. Population (Group of organisms in the same area)
6. Community (Populations that live together in 1 area)
7. Ecosystem (Community and nonliving surroundings)
8. Biosphere (Earth's part that contains all ecosystems)
What are some different branches of biology?
3. Paleontology=Ancient Life
How can cell cultures be used?
They can test cell responses under controlled conditions, to study interactions between cells, and to select specific cells for further study