Unit 1: The Nature of Science Standards BIO.1 a-m

What is Biology? The study of life, or all types of organisms. An organism is any individual living thing. How do you know something is living?

The Martian and the Car Marty Martian was sent to Earth by the Martian government to find life. While on Earth, Marty captured a car and brought it back to Mars. He thought he'd found a good example of life on Earth. The Martian government does not believe that the car Marty brought back is alive. Marty must stand trial for failing to perform his Martian duties. At the trail, Marty spoke in his defense. "I first saw these life forms rolling along roads in great numbers. They were giving off thick clouds of poisonous waste as they moved. They seemed to exhibit herding behavior, as many of the cars moved in the same direction. They appeared to have a great deal of energy, some of them moved faster than 60 kilometers per hour. When one of these life forms stopped or slow down, the others behind it responded. They slowed down and gave off a reddish light from the back, and sometimes they would make honking noises. I observed that they would stop to feed on a liquid substance." Group 1: Take the part of Marty's defense attorney and make a good case for the car's being alive. Group 2: Be the prosecutor and show that the car is a nonliving thing. List as many reasons as you can.

The Martian and the Car Group 1: Defense Living! Group 2: Prosecution Not Alive!

Characteristics of Life 1. Made up of Cells 2. Share a Universal Genetic Code (DNA) 3. Grow and Develop 4. Reproduce 5. Respond to Stimuli 6. Require Energy 7. Maintain Homeostasis 8. Evolve

Cells Basic unit of life. Different cells have different jobs.These cells help an organism be organized. For example, cells make up tissues, tissues make up organs, organs make up organ systems, and organ systems make up an organism.

Levels of Organization Atom (smallest) Molecule Organelle Cell Tissue Organ Organ System Organism Population Community Ecosystem Biome Biosphere (largest)

Genetic Code Organisms store the information they need to live, grow, and reproduce molecule called DNA. DNA contains all the instructions for the creation of proteins. These proteins control almost all functions in your body.

Growth and Development Cells divide from pre-existing cells to produce new cells. More Cells = Larger Organism

Reproduction Passing on genetic information from one generation to the next. Allows species to survive, if organisms can no longer reproduce they will become extinct.

Response to Stimuli Stimulus: anything in the internal or external environment that causes a reaction Response: the reaction to the stimulus Example: If you touch something hot, you pull your hand away

Obtain and Use Energy The sun is the original energy source Plants, producers, use the sun to make food and through photosynthesis Animals, consumers, eat plants and other organisms Food is then broken down into usable energy through a process called cellular respiration

Maintain Homeostasis Homeostasis: maintaining constant internal conditions like, temperature, pH, and blood sugar Example: When you get hot you sweat to bring your body temperature down

Characteristics of Life Collage Get one sheet of construction paper and a few magazines. Find pictures in the magazines to represent the 8 characteristics of life. Cut out the pictures and paste them on the paper. Label each picture with the characteristic of life that they represent. Under each characteristic, explain why the picture you chose represents that characteristic. Put your name on the back of the paper and turn in it to your class tray. Clean up all paper scraps and put away your glue sticks, scissors and magazines. You will not be allowed to leave class until the room is clean

THE SCIENTIFIC METHOD Standards BIO.1 a,b,c,e,f,k,m

Biologists… Research Diseases Develop New Technologies Improve Agriculture Protect and Help the Environment

Thinking Like a Scientist All scientific inquiry begins with an observation Using your senses to study the world around you Inferences can be drawn from these observations to form conclusions about the world around you

What’s in the Box? Observations Using the senses to study the world Inferences A conclusion based on evidence and reasoning

The Scientific Method Start with a Problem or Question You Have About the World Around You Form a Hypothesis Based on prior knowledge, research, previous published experiments Must be Testable Generally written in the following way “If...independent variable…then…dependent variable…” Conduct an Experiment Collect and Analyze Data Draw Conclusions Report Findings

Scholarly Journals Scholarly journals are often key resources for academic research Journal articles are "peer- reviewed," meaning their content is reviewed and approved by experts in the discipline Encyclopedias and textbooks are sometimes outdated and biased

Parts of an Experiment Controlled Experiment: A scientific investigation in which both the control group and experimental groups are kept under similar variables Control Group: the group which remains “normal”, unchanged Experimental Group: the group that was changed Independent Variable: what you change in an experiment Dependent Variable: the result of what you changed Constant: parts of the experiment that remains the same for all groups

Sources of Error Things that happens in an experiment that affect your data Error can be caused by the following: ‘Sloppy’ experimenter Hard to read equipment Miscalibrated equipment Operator bias Variation in experimental conditions All error can be minimized by repeated measurements and using an average value

Practice! A student investigated the effect of radiation on the germination of bean seeds. He thought that exposure to radiation would limit the seeds ability to germinate (grow) much like ultra-violet light causing skin cancer. Three hundred seeds were soaked in distilled water for one hour. They were then divided into three groups. One group was placed in a microwave oven on high for three seconds. Another group was microwaved on high for six seconds. The last group was not microwaved. The seeds were then planted in three separate flats and given the same amount of water. The seeds were then planted in three separate flats and given the same amount of water. The flats were placed in a location with a constant temperature of approximately 27 degrees Celsius. Each day for two weeks the number of seeds that germinated each group was recorded. Results: No Radiation: 88/100 beans germinated 3 Seconds of Radiation: 54/100 beans germinated 6 Seconds of Radiation: 33/100 beans germinated

Questions: 1. What is the problem? 2. What is the hypothesis? 3. Independent Variable? 4. Dependent Variable? 5. Control Group? 6. Constants? 7. Was the hypothesis supported or rejected by the data collected? 8. Sources of Error?

Scientific Theories Theory: proposed explanation for a wide range of observations and experimental results that is supported by a wide range of evidence Examples: The Cell Theory, The Theory of Evolution, The Big Bang Theory In contrast, a law describes a truth that is valid everywhere in the universe. This is based on empirical data and can usually be summarized into a mathematical equation. Examples: Universal Law of Gravitation, Newton’s Laws of Motion Scientists must always be willing to revise theories and conclusions as new evidence about the living world is gathered; new theories that better explain observations and experimental results can replace older theories.

GRAPHING AND DATA Standards BIO.1 d,e,g

Data Tables and Graphs Visual representations of results that make the conclusions of an experiment easy to understand. Two Types of Data: Qualitative: descriptive Quantitative: numerical Three Types of Graphs: Line: Shows relationship between independent (x) and dependent (y) variables Bar: Useful for comparing information Pie: Shows parts of a whole (percentages)

For Every Graph You Must Have the Following: A Title Labeled X-Axis: Independent Variable Labeled Y-Axis: Dependent Variable Appropriate Units (cm, m, s,…) Legend When Necessary

Line Graph

Bar Graph Favorite Movie Type Number of Students Romance6 Sci-Fi3 Action and Adventure 10 Comedy12 Horror5

Pie Chart Hair ColorPercentage of Class Brown50 % Red15 % Blonde35 %

Practice! Which Type of Graph Best Represents THIS Data? FlavorNumber of Students Percentage Vanilla Chocolate Strawberry Other Total:100%

Describing Data Measure of Central Tendency: one number that is most typical of the entire set of data Mode: number occurring most often Median: middle value when data is ordered from highest to lowest Mean: average Variation: spread within the data Range: difference between the smallest and largest measures

Practice! Find the mean, median, mode, and range for the following set of data. DayHeight of Tomato Plant (inches)