Chapter 1 The Science of Life Section 1-2 Themes in Biology Be Able To Identify three important themes that help explain the living world. Explain how life can be diverse, yet unified. Describe how living things are interdependent. Summarize why evolution is an important theme in biology. Key Terms Key Terms: Pg 10.

Themes in Biology Diversity and Unity of Life What unites all the diverse life forms of our planet? Organisms transmit hereditary information or the genetic code of life to their offspring, in the form of DNA. Organelles carry out the instructions of the genetic code for cellular functions. All living things share certain genes yet not all have the same set of genes. The tree of life can be divided into 3 categories or domains. genes The most important information in DNA is found on short segments called genes.

Themes in Biology Interdependence of Organisms EcologyEcology is the study of the interactions of organisms with one another and with their environment. To survive all organisms depend on the availability of certain substances from their environment and the stability of the environment depends on the healthy functioning of its organisms. What animal species has impacted its environment the most? The Northern Snakehead. How Invasive?

Themes in Biology Evolution Populations of organisms change or evolve over generations to meet the demands of the environment. Natural selection is the process by which organisms with favorable variations reproduce at higher rates than those without such variation, driving evolution. How does the arctic hare adapt to the seasonal changes in its environment? Why the change in fur color?