Scientific Process and Themes of Biology Chapter 1 Scientific Process and Themes of Biology

1-3 Scientific Process Scientific knowledge is acquired using a rigorous process True science always follows this process Don’t be fooled by pseudoscience!

Steps to Process Collecting observations Asking questions Forming hypotheses and making predictions Confirming predictions Drawing conclusions

Observations Using your senses, observe the world around you Document your observations

Asking Questions Ask questions based on your observations What was causing your observation?

Forming Hypotheses and Predictions Hypothesis-a statement that can be tested by more observations or experimentation Prediction-expected outcome of a test

Confirming Predictions Use a controlled experiment (must have certain key parts) Control Group-group in an experiment that receives no experimental treatment

Independent Variable-the factor that is varied in the experiment Dependent Variable-variable that is measured in the experiment

Drawing Conclusions Was the hypothesis supported or rejected? Why did the data support or reject the hypothesis?

Publishing Results Most experiments are eventually published Accumulation of related hypotheses that have been tested many times by many scientists can result in a theory

1-1 Themes of Biology Biology is the study of life There are 7 properties of life

Cellular Organization Reproduction Metabolism Homeostasis Heredity Responsiveness Growth and Development

The science of Biology is unified by 7 distinct themes These are different then the 7 properties of life!

Unifying Themes of Biology (1)Cellular Structure-all living things are made of one or more cells (2)Reproduction-all living things must reproduce (3)Metabolism-the sum of all chemical rxns carried out inside an organism

(4)Homeostasis-maintaining a stable environment inside of the cell (5)Heredity-passing characteristics from parents to offspring Gene-set of inherited instructions for making proteins Mutation-change in the DNA of a gene

(6)Evolution-change in the inherited traits of species over time Species-group of genetically similar organisms that can produce fertile offspring Natural Selection-organisms with favorable genes are more likely to survive and reproduce

(7)Interdependence-organisms have evolved to interact with other organisms Ecology-the science that studies the interactions of living organisms with the nonliving part of their environment