Chapter 1

1. Chapter 1 Principles of Life

2. Concept 1.1 • Living organisms share common aspects of structure, function and energy flow • Evidence we currently have suggests that all living things have a single common ancestor.

3. All organisms • Are composed of a common set of chemical components. • Genetic information that uses a nearly universal code to specify the assembly of proteins • Convert molecules obtained from their environment into new biological molecules • Extract energy from the environment and use it to do biological work • Regulate their internal environment • Replicate their genetic information in the same manner when reproducing themselves • Share sequence similarities among a fundamental set of genes

4. Life’s Calendar • Our History in 1 minute • Our History in 24 hours

5. Concept 1.2 Genetic Systems Control the Flow, Exchange, Storage and Use of Information • Genome – sum total of all the information encoded by an individual’s genes • Genes – portions of the DNA that can be decoded to build proteins. • All the cells in an organism have the same DNA but different genes are used in different cells.

6. Think of DNA as the letters in the words of a recipe • The recipe is a gene • The cookbook is the genome. • We all have a very similar cookbook…very minor differences from one person to the next • Each of our cells have the entire cookbook in them but only read or use about 3% of the recipes.

7. Concept 1.3 Organisms Interact with and Affect Their Environments • Hierarchy –biological systems are organized on a hierarchy from basic building blocks to complete functioning ecosystems. • Integration – Much of biology involves integrating investigations across many of the hierarchical levels.

8. Organisms interacting and affecting their environment • With energy transformations: Metabolism - sum total of all the chemical transformations and other work done in all the cells of an organism • With regulatory systems: homeostasis - the maintenance of a narrow range of conditions in the internal environment • With competition and cooperation: symbiosis – a close, long-term relationship between individuals of two different species

9. Evolution Explains Both the Unity and Diversity of Life • Evolution – a change in the genetic makeup of a population through time. • The result of this constant change is diversity. • The first unit of study we’ll cover after this introduction is evolution.

10. Why are we starting with evolution? • “Nothing in biology makes sense except in the light of evolution” • Theodosius Dobzhansky • This quote emphasizes the need to integrate an evolutionary perspective into all aspects of biological study.

11. Science is Based on Quantifiable Observations and Experiments • Not only should we make observations of the natural world but we also have to be able to quantify our observations. • This means that we have to have mathematical and statistical calculations about the data we are collecting.