Biology Study of life
Chapter 1 Biology ..\..\Integrated\PowerPointsHOlt\Ch01\60001.swf
Biologist Study • Study Diversity of Life (ex. Jane Goodall studies “ How chimpanzees behave in wild”) • Research Disease • What causes disease? • How does body fight disease? • Develop vaccines • New medicines • Develop technologies • “bionic” hand • Store and transport blood plasma for transfusions-saved countless soldiers life WWII. • Improve Agriculture • Preserve the environment
Characteristics Of Living Things LIVING THINGS….. • made of cells • based on genetic code • reproduce • grow and develop • adjust to their surroundings--respond • adapt and evolve • obtain and use energy • maintain stable internal environment
Living Things Are Organized Composed of one or more cells that are based genetic code. Organization: an arrangement of parts (cells) for the performance of the functions necessary to life
Organisms Number of Cells • Multicellular – Organisms made of many cells (ex. monkey and trees) • Unicellular – One cells organisms ( ex. Amoeba)
Types of Cells Prokaryotes – an organism, characterized by the absence of a nuclear membrane and by DNA that is not organized into chromosomes. (ex. bacteria) Eukaryotes – an organism composed of one or more cells containing visibly evident nuclei and organelles (ex. plants and animals)
Living Things Make More Living Things Reproduction: Production of an offspring by an organism. Species: Organisms that can interbreed and produce fertile offspring in nature. (Reproduction is not essential for an individual organism, but for continuation of a species)
Types of Reproduction • Sexual – Requires two parents and offspring are not identical • Asexual – Requires one parent and offspring identical
Living Things Change During Their Lives single cell grows and takes on the characteristics of its species. Growth: Increase in the amount of material and formation of new structures in an organism. Development: All of the changes that take place during the life of an organism.
Living Things Adjust to Their Surroundings Environment: Living and nonliving surroundings to which an organism must constantly adjust (air, water, weather, temperature, other organisms, other factors) Stimulus: Any condition in the environment that requires an organism to adjust Response: A reaction to stimulus
Homeostasis Organism’s regulation of its internal environment to maintain conditions suitable for survival.
Obtain and use materials and energy Used to grow, develop and reproduce Metabolism-chemical reactions through which an organism builds up or breaks down materials.
Living Things Adapt and Evolve Adaptation: Evolution of a structure, behavior, or internal process that enables an organism to respond to stimuli and better survive in an environment. Evolution: Gradual accumulation of adaptations over time.
Do Now: Suppose you want to test phone cover/skins to decide which is best for protecting your cell phone. What materials would you need? What procedure would you follow? How would you determine which cover best protected your phone?
A common misperception of science is that science defines "truth." Science does not define truth; rather, it defines a way of thought. It is a process in which experiments are used to answer questions. This process is called the scientific method.
The Advantages of Method Clarifies our thoughts Uses human potential Ends aimless wandering Aids in transfer of learning Guides us to new knowledge Trains for change and innovation Helps ideas gather shape Is a repeatable procedure Organizes our thoughts Encourages thinking Wasted time Quick fixes Wrong analysis Wasted energy Haphazard guesses Wandering aimlessly No Solutions Mistakes and errors Confusion Misdirection The Opposite of Method is Chance
Chapter 1 Scientific Method
Scientific Method: Series of organized steps/procedures that scientist use to solve problems and answer questions.(A process for investigating nature) • Observing and Stating the Problem • Collecting Data/Gathering Information • Form a Hypothesis • Perform an Experiment • Analyze Data • Draw Conclusions based on your hypothesis and experiment. • Report Results
Observing /Observations Sees, hears, or in some way notice something no one has noticed before. If the facts don't fit the theory, change the facts.-- Albert Einstein
State the Problem A scientist can’t begin to solve a problem until it is clearly stated. For instance, when going to the doctor you tell the doctor what is wrong. (e.g. you have a sore throat) In lab the Problem is always stated in the form of a question.
Gather Information After defining your problem you need to gather information For instance, a doctor would ask how long you have had a sore throat, take your temperature, and examine your throat.
HypothesisGreek: hypo-”under”, thesis-”placing” A tentative explanation for a question or problem that can be formally tested. For instance, based on experience, the doctor theorizes that you have strep throat which can be tested in a laboratory. ..\..\Integrated\PowerPointsHOlt\Ch01\80003.swf
Perform an experiment A procedure/series of steps that test a hypothesis under controlled conditions.
Chapter 1 Controlled Experiment and Variable ..\..\Integrated\PowerPointsHOlt\Ch01\80004.swf
Using Tools-Beakers, test tubes, hot plates, petri dishes, thermometers, dissecting instruments, balances, rulers, microscopes, centrifuges, radiation detectors, etc. • Maintaining Safety • Minimize hazards • Know your safety symbols • Your responsibility to protect yourself as well as your classmates. Experiment Considerations
Experimental Considerations Data Information obtained from experiment Quantitative: Numerical form (distance, height) Qualitative: Verbal Form (descriptions, behaviors) Sometimes referred to as experimental results.
Control group- group in which all conditions are kept the same (Standard used to compare with the outcome of a test) Experimental group-Test Group; receives the variable Experiment Factors
Controlled Experiments:Only one conditions changes • Variable-The factor being tested in an experiment • Independent Variable-Condition in an experiment that is changed. The only variable that affects the outcome of the experiment. (temperature, nutrients, light, soil) • Dependent Variable-A condition that results from change. Depends on changes from independent variable. (height, color, etc)
Presence of bacteria Soil nutrients Vitamins Play Wii Fit 30 m/d petri dish with growth medium Growth rate Plant height Cholesterol Levels Weight Growth on dish Independent Dependent
Analyze Data Data collected from the experiment is analyzed. For your sore throat, a lab technician identifies the growth and records data in your chart.
Draw Conclusion Data is used to draw conclusions. A conclusion is a logical answer to a question based on data and observations of the test material.
Does your data support or reject your original hypothesis? If the data shows that your sore throat was caused by another kind of bacterium, you don’t have strep throat and the original hypothesis is rejected. The doctor must now revise the hypothesis to include a different cause of sore throat. If the hypothesis was supported a scientist will sometimes perform additional experiments and gather more data to strengthen their conclusion. If the experiment supports the hypothesis that you have strep throat, and the doctor feels the data is sufficient to be statistically valid they may skip further experimentation and proceed to reporting results.
Reporting Results The last step in solving a problem scientifically is to do something with the results. This includes sharing data and suggesting remedies. Your doctor may prescribe an antibiotic to kill the bacteria.
Chapter 1 Conducting experiments • No experiment is a failure • The results of every experiment can be used to revise the hypothesis or plan tests of a different variable.
Scientific Theory Hypothesis successfully passes many test over a long period of time and proves useful in knitting together a large body of scientific work, it takes on the status of Theory. Theory- A tested explanation of a broad segment of basic natural phenomena. e.g. Atomic Theory Be Valid: explain observations be repeatable be predictable
Scientific Law A concise statement in words or a mathematical equation, about a fundamental relationship or regularity of nature. e.g. During a chemical reaction, no detectable gain or loss of mass occurs. Does not explain behavior of nature, it just states the generalized experimental finding.
Chapter 1 Comparing Theories and Laws ..\..\Integrated\PowerPointsHOlt\Ch01\80007.swf
Activity Create a chart that: Defines scientific law, theory and hypothesis Provide qualities/characteristics that distinguish each of them (how do I know it’s a law, theory or hypothesis) Examples of each
Research • Quantitative—Controlled experiments that results in counts or measurements. • Numerical data • Graphs and tables
Descriptive research • Observational data; Written descriptions of what scientist observes.
Ethics Moral principles and values held by humans -social, ethical moral concerns when planning an investigation.
Technology Application of scientific research Making improvements in human life and world around us Increase production of food Reduced manual labor Reduction of waste and environmental pollution.
Metric System A decimal system of weights and measurements based on meter and kilogram.
1670—Gabriel Moulton, a French mathematician, proposes a measurement system based on a physical quantity of nature and not on human anatomy. 1790—The French Academy of Science recommends the adoption of a system with a unit of length equal to one ten-millionth of the distance on a meridian between Earth’s North Pole and equator. 1870—A French conference is set up to work out standards for a unified metric system. Brief Chronological History of the Metric System