The Science of Marine Biology

1. The Science of Marine Biology

2. Why do we study Marine Biology? • Major Food Source • Medicine • Major source of oxygen • Carbon dioxide “sink” (photosynthesis) • Predict weather patterns • Recreation • Solve problems caused by marine organisms • Predict effects of human activities

3. The HMS Challenger ExpeditionFirst major oceanographic expedition • For three and a half years sailed around the globe collecting information and gathering samples. • Set new standards for studying the ocean. • Systematic measurements were made and meticulous records were kept. • Laid the foundations of modern marine science

5. Alvin • http://www.youtube.com/watch?v=bBf5x72Rc60 (Deep sea wave)

6. The Scientific Method • A set of flexible procedures to answer a question or problem using direct observations • Scientists may use tools to enhance their observations • Induction – specific observations lead to general conclusions • Deduction – general principles are used to make specific predictions • Fig. 1.19

8. Steps of the Scientific Method • Observe a selected part of nature and then state the problem you wish to solve in the form of a testable hypothesis. • Formulate a hypothesis (“educated guess”). Often stated with the words if and then in order to devise an experiment to test it. • A hypothesis can be supported by experimental evidence or it may be proven false by experimental data.

9. The Scientific Method Experiment a. In a controlled experiment two groups are tested: one that is exposed to the variable and one that is not. (Fig. 1-20) b. Variable – what you are changing or measuring 1. independent variable – what you are changing 2. dependent variable – what you are measuring

10. The Scientific Method • Make observations and record results • Analysis/Conclusion – do results support or disprove the hypothesis • Publish results – other scientists can repeat and see of they get the same results

11. A bar graph is used to compare data and show relationships at a glance.

12. A line graph shows the relationships between variables (i.e. – independent/dependent)

13. Scientific Theories • A theory is a statement made based on a broad range of phenomenon • Example – Theory of Evolution – species evolve over time with natural selection being the driving force. • Theory is supported by; fossil record, comparative anatomy, embryology, DNA analysis

14. Scientific Laws • A statement that is true – usually based on a mathematical equation • Charles Law – V2 = V1 T2 T1 (volume of gas varies directly with temp.) • Boyles Law - V2 = V1 P1 P2 (pressure is inversely proportional to volume

15. Bar Graphs and Line Graphs • Using the information in the following slide construct one bar graph and one line graph in your lab book. • Copy the data table into your lab book. • What can you conclude from the information in your graphs?

16. Average speed of snails at different temperatures (cm/min)