Chapter 1 - The Science of Biology Flashcards
Properties of Life - Living organisms:
- are composed of cells
- are complex and ordered
- respond to their environment
- can grow and reproduce
- obtain and use energy
- maintain internal balance
- allow for evolutionary adaptation
Basic unit of life is the
cell
Levels of Organization - Cellular Organization
atoms - molecules - organelles - cells
Levels of Organization - Organismal Level
tissues - organs - organ systems - organism
Levels of Organization - Population Level
population - species - community - ecosystem
Emergent properties
new properties present at one level that are not seen in the previous level
(Each level of organization builds on the level below it but often demonstrates new features.)
Science aims to understand the natural world through
observation and reasoning
Much of science is purely descriptive.
Deductive reasoning
uses general principles to make specific predictions
Inductive reasoning
uses specific observations to develop general conclusions
Scientific method (systematic approach to gain understanding of the natural world)
- Observation
- Hypothesis formation
- Prediction
- Experimentation
- Conclusion
hypothesis
a possible explanation for an observation
(-must be tested to determine its validity
-is often tested in many different ways
-allows for predictions to be made)
experiment
- tests the hypothesis
- must be carefully designed to test only one variable at a time
- consists of a test experiment and a control experiment
reductionism
break a complex process down to its simpler parts
models
to simulate phenomena that are difficult to study directly (have limitations and are only as good as their data)
Germ Hypothesis (related to nutrient broth experiment)
preexisting microorganisms present in the air can contaminate the nutrient broth
Spontaneous Generation Hypothesis
Living organisms can be generated spontaneously from nonliving organic molecules in broth
scientific theory
- is a body of interconnected concepts
- is supported by much experimental evidence and scientific reasoning
- expresses ideas of which we are most certain
Proposed that evolution occurs by natural selection
Charles Darwin
evolution
modification of a species over generations
(“descent with modification”
proposed by Darwin)
natural selection
individuals with superior physical or behavioral characteristics are more likely to survive and reproduce than those without such characteristics
(proposed by Darwin)
Darwin’s evidence - Similarity of related species
Darwin noticed variations in related species living in different locations. (specifically finches from the Galapagos Islands)