1. Why Study Biology? Living things do not exist in isolation – depend upon other living & nonliving things. Studying biology helps to preserve organisms and help to solve other problems. Scientists create inferences – logical interpretations based on prior knowledge.  Ex. Studying fresh water reservoir.

2. Inferences vs. Observations Statement 1.Object A is round and orange 2. Object A is a basketball 3.Object C is round & black & white 4.Object C is larger than Obj. B 5.Obj. B is Smooth 6.Obj. B is table tennis ball 7. Each object is used in a diff. sport Observation or Inference 1. Observation 2. Inference 3. Observation 4. Observation 5. Observation 6. Inference 7. Inference & Observation

3. Scientific Method The methods that biologists use  The common steps used to gather info, to solve problems are the scientific methods.  Observing the world around you can lead to questions which require an answer. Hypothesis: an educated guess about the out come of an experiment.

4. Experimenting To a scientist, an experiment is a procedure that tests a hypothesis by the process of collecting info, under controlled conditions. What is a controlled experiment?  The standard in which all conditions are kept the same = the control (control group) – the test group is the experimental group in which all conditions are kept the same except the one being tested.

5. Designing an Experiment Only one condition changes @ a time (called the independent variable) – the second condition that is a result of the independent variable is the dependent variable. On a graph the Independent variable is along the x- axis. The DV is on the y- axis

6. Example Experiment An apple tree farmer wants to begin using a certain fertilizer to have better crops. Currently he only uses water on his crops. He is planning on testing 3 different fertilizers on his orchard. He will be looking at the size of the apples for his decision. After the season the fertilized apples were 5 grams larger than water grown apples. The farmer has decided to use fertilizer on his crops.

7. Data is often in numerical form. (Quantitative Data)  Measurements of time, temp, length etc  As well as counts, such as # of something May be expressed in verbal form, such as observations of animals. (Qualitative Data) Data Gathering

8. Laws and Theories A hypothesis that is supported by many separate observations & experiments, usually over a long period time is known as a theory. Enables scientists to predict new facts & relationships.  Ex. Big Bang Theory, Theory of evolution Laws are facts of nature and hypotheses that can be proven regularly.  Ex. Law of Gravity

9. Metric System Scientists always report data in modern form of metric system called the International System of measurements (SI) Measurements can have prefixes with the basic units. Measurement UnitSymbol Massgrams.g Time seconds.s Volumeliter.l Lengthmeter.m Temperature CelsiusCºCº

10. Characteristics of Living Things How can you tell the difference between a living and non-living thing? All living things have the following:  Have an orderly structure, made up of cells  Produce offspring  Based on a universal genetic code.  Obtain and use materials and energy  Grow and develop  Adjust to environmental changes – Internal and external.

11. Levels of Organization 1. Molecules – units of chem. Compounds. DNA, H 2 0, 2. Cells – smallest function unit of life, nerve cell 3. Groups of Cells --Tissues, Organ, Organ Systems 4. Organism – Individual living thing. 5. Population– group of the same organisms 6. Community – multiple populations living together. 7. Ecosystem– living & nonliving factor living together. 8. Biosphere – all living matter on Earth

12. All living things show an orderly structure (organization) – have specialized parts that perform particular functions – whether unicellular or multi cellular, all structures & functions of the organism together form an orderly living system. Ex. Humans have lungs, heart, brain, etc.. Each with its own function. Living things are organized

13. Living things make more living things. The most obvious characteristic is reproduction (the ability to make offspring) – for life to continue, organisms must replace themselves / reproduction is essential for the survival of the species, not the individual. Reproduction can me asexual or sexual reproduction types.

14. 3. Living things change during their lives: growth results in an increase in the amt. of living material & the formation of new structures – different parts of the organism will grow at different rates. All changes that take place during the life of an organism is called development.

15. 4. Living things can adjust to their surroundings: constantly interfacing with their environment (includes air, water, weather, other organisms.) – conditions that require adjustment are known as stimulus – the reaction by the organism is its response. – The ability to respond to stimuli is important to the survival within the environment. Living things adjust to surroundings

16. Any structure, behavior, or internal process that enables an organism to respond to stimuli & better survive is known as adaptation. – Adjustments to internal stimuli help organisms maintain a steady internal environment ( regulation of internal environment to maintain conditions suitable for life is called homeostasis.) Adjustment to surroundings continued

17. Considering Ethics in Science Most scientists state that scientific research & its results are neither right nor wrong, good nor bad – ethics is a study of the standards of what is right & wrong. Many scientists believe they should be involved in the decisions about the consequences of their work & how that work is applied – but once a discovery is made, it is up to the people of society to make the decisions.

18. Thinking about what happened. Must come to a conclusion: Was the hypothesis supported by the data? Was is not supported? Is more data needed? Data only confirmed if repeating that experiment several times yields similar results.

19. Tools of Science Microscopes -

21. What is Biology ? Key aspect of biology is simply learning ~ the different types of living things around us By asking such ?’s as what, why, how, you develop general principles and rules that indicate there is order in the natural world.