1. Chapter 1 The Science of Biology

2. 1-1 What is Science? Goal of Science –Investigate and understand the natural world –Explain events and use that information to make predictions

3. 1-1 What is Science? Thinking like a Scientist –Observations: generally involves using senses to gather information –Data: information gathered from observations –Inference: logical interpretation based on prior knowledge or experience –Hypothesis: proposed scientific explanations for a set of observations

4. 1-1 What is Science? Biology can solve real world problems –World Population Over 7 Billion people –Need Room »Rain Forests being destroyed, species going extinct –Need Food »Need crops to grow more efficiently, genetic engineering

5. 1-2 How Scientists Work Science is based on careful observations –Shared observations help solve scientific puzzles

6. 1-2 How Scientists Work Scientific Method –Collecting Observations An observation is the act of perceiving a natural occurrence that causes someone to pose a question –Asking a Question –Form a hypothesis A hypothesis is a proposed explanation for the way a particular aspect of the natural world functions

7. 1-2 How Scientists Work Scientific Method –Design an Experiment A controlled experiment compares an experimental group and a control group and only has one variable The control group provides a normal standard against which the biologist can compare results of the experimental group. The experimental group is identical to the control group except for one factor The experimenter manipulates the independent variable. The experimenter measures the dependent variable because it is affected by the independent variable

8. 1-2 How Scientists Work Scientific Method –Collect and Analyze Data Scientists analyze data to draw conclusions about the experiment performed. –Form a Conclusion An inference is a conclusion made on the basis of facts and previous knowledge rather than on direct observations –Repeat

9. 1-2 How Scientists Work Applying Results and Building Models –Scientists often apply their findings about the natural world to solve practical problems. –A theory is a set of related hypotheses confirmed to be true many times, and it can explain a great amount of data

10. 1-2 How Scientists Work Communicating Ideas –Publishing a Paper Scientists submit research papers to scientific journals for publication. In peer review, the editors of a journal will send submitted papers out to experts in the field who anonymously read and critique the paper

11. 1-3 Studying Life Organization –Cells- smallest unit of life, contain organelles Unicellular- single celled organism Multicellular-organism of more than one cell –Tissues –Organs –Organ System –Organism

12. 1-3 Studying Life Reproduction –Passing on genetic info Asexual reproduction – one parent Sexual reproduction – two parents

13. 1-3 Studying Life Heredity –Information passed through genes (DNA) Set of inherited instructions

14. 1-3 Studying Life Growth and Development –All living things grow and increase in size Development – process of maturation

15. 1-3 Studying Life Metabolism –Sum of all chemical reactions in the body Take in, transform, and expend energy

16. 1-3 Studying Life Respond to their environment –Organisms detect and respond to stimuli from their environment

17. 1-3 Studying Life Homeostasis –Organisms keep their internal environment stable even with changes in the external environment Water content Temperature regulations

18. 1-3 Studying Life Living things change over time –Basic traits inherited do not change, but given groups of organisms typically evolve

19. 1-3 Themes in Biology Interdependence –All organisms depend on other organisms Ecology – branch of biology that studies organisms interacting Ecosystems – communities of species living together and interacting in an environment

20. 1-3 Themes in Biology Diversity and Unity –All life is divided into 6 different kingdoms Even diverse within the kingdoms –All organisms have things in common Heredity info in DNA Species may have split from a common ancestor

21. 1-3 Themes in Biology Evolution of Life –Evolution – process of modification, the change is in inherited traits –Natural selection – organisms with more favorable traits are better able to survive and thus reproduce

22. Section 4 Tool and Techniques Common measurement system-metric system Based on multiples of 10 –Length is measured in meters –Mass is measured in gram –Volume is measured in liter –Temperature is measured in degree Celsius (°C)

23. Section 4 Tool and Techniques Light Microscopes –A compound light microscope is a microscope that shines light through a specimen and has two lenses to magnify an image. –Four major parts of a compound light microscope are the ocular lens, objective lens, stage, and light source

24. Section 4 Tool and Techniques Light Microscopes –The ocular magnifies the image. (10x) –The objective lens enlarges the specimen. –The stage is a platform that supports slides with specimens. –The light source is a light bulb that provides light for viewing images.

25. Section 4 Tool and Techniques Magnification and Resolution –Magnification is the increase of an object’s apparent size. –Resolution is the power to show details clearly in an image.

26. Section 4 Tool and Techniques

27. Electron Microscopes –In an electron microscope, a beam of electrons produces an enlarged image of the specimen. –Electron microscopes provide greater magnification and resolution than light microscopes.