Chapter 1: What is Biology?
What is Biology? »Bio-: means life – ology: Study of Biology is the study of life/living things
Branches of Biology Zoology: study of animals Botany: study of plants Paleontology: study of ancient life
Why Study Biology? Live longer, healthier lives Use evidence to learn about the natural world Pleasure of learning Understanding the “web of life” (all organisms are connected to each other) Understand/control our future –Why things happen and what could happen in the future
Themes in Biology Flow of energy through systems –Cell Organism Biosphere –Powers all life processes Interaction of systems –Interacting with the environment Unity within diversity
Themes in Biology Homeostasis: regulation of an organism’s internal environment to maintain survival Evolution: gradual change in a species through adaptations over time Biology is always expanding and changing the field of study
Characteristics of All Living Things 1. Made up of cells –Unicellular (made of one cell) vs. multicellular (made up of many cells)
2. Highly organized 3. Use energy –Ex: metabolism Building chemical substances Energy requiredEnergy released Breaking down chemical substances
4. Growth and Development Growth: increase in the amount of material (size) and the formation of new structures Development: all of the changes that take place during an organism’s lifespan
5. Have a life span 6. Reproduction: sexual vs. asexual –Needed for the survival of a species –Most multicellular species reproduce sexually 7. Respond to a stimulus (ex: blink/flinch when something is thrown at you) 8. Adaptations: evolution –Variation of traits that are inherited 9. Maintain homeostasis: internal balance
Matter Organization atoms elements molecules
6 most abundant elements in all living things –Carbon, Hydrogen, Oxygen, Nitrogen, Sulfur, and Phosphorus Organelles and cells –Organelles are mini “organs” found in every cell
cells tissues organs organ systems Organisms unicellular, multicellular, or colonial Few Many
Species
Populations
Communities
Ecosystems
Biomes
Biosphere
Bell Ringer: 1.List the 9 characteristics that classify a mushroom as a living thing. 2.What is the name for a collection of living matter enclosed by a barrier that separates is from its surroundings? a.cellb. cell culture c. cell fractionation d. DNA 3. What is the name for a combination of chemical changes that builds up or breaks down material in an organism? a. homeostasis b. metabolism c. sexual reproduction d. cell culture
The Scientific Method: shows/mythbusters/videos/surreal- gourmet-hour.htmhttp://dsc.discovery.com/tv- shows/mythbusters/videos/surreal- gourmet-hour.htm
Scientific Method common steps used to gather information and answer questions (8 steps) 1. make observations: use your senses 2. state the problem 3. gather information 4. make a hypothesis: an explanation for a question or a problem that can be tested –has to be able to be tested can be disproved –is not a guess or a fact (sometimes cannot be 100% proven accurate)
5. test the hypothesis through an experiment: procedure that tests a hypothesis by collecting information under controlled conditions 6. collect and gather data: information obtained from the experiment 7. draw a conclusion: was the hypothesis correct or incorrect? 8. publish results in scientific journals –allows other scientists to repeat experiment –Ex: Redi’s and Pasteur’s experiments (disproved spontaneous generation)
Theory Well-supported hypothesis Well-tested explanation Can be revised or replaced by another theory
Controlled Experiments involve two groups: control group and experimental group control: standard by which all conditions are kept the same
experimental group: the test group in which all conditions are kept the same except for the single condition being tested –only one condition is changed at a time –independent variable: what is being changed (manipulated variable) affects the outcome of the experiment
dependent variable: results from the change of the independent variable (responding variable) –changes to it depend on changes made to the independent variable Not all experiments are controlled (ex: field studies)
Qualitative Data Using the senses to describe observations and gather information What you see, smell, taste, touch…etc. Describe using words
Quantitative Data Experiments yield numerical data System of measurement (SI): metric system –Base units: length meters (m) mass grams (g) volume liters (L) time seconds (s) temp °C –Based on multiples of 10 Prefixes: –kilo (1000) –hecto (100) –deca (10) –deci (0.1 or 1/10) –centi (0.01 or 1/100) –milli (0.001 or 1/1000)
Science and Society Knowledge gained through research is never good or bad Attempts to explain how and why things happen Science is objective: can be tested and measured Society is dealing with the subjective –Social, moral, and ethical concerns (right vs. wrong)
Pure science –Gaining knowledge through discovery Applied science –Technology that applies knowledge to fit society’s needs and problems –Involves making improvements in human life
Inductive reasoning –Reasoning about something from a set of facts –Start with a specific statement or fact make a general statement Deductive reasoning –Suggesting something from a set of facts or general rules –Start with a general rule or fact make a specific statement from that general rule
Microscopes Light vs. electron Electron: SEM vs. TEM
Lab Techniques Cell cultures-make copies Cell fractionation –Separate into parts
Bell Ringer: 1.Place the following steps of an experimental investigation in the correct order: __ Form a hypothesis __ Ask a question __ Record and analyze results __ Draw a conclusion __ Set up a controlled experiment 2. What type of microscope allows light to pass through the specimen and uses two lenses to form an image? a. TEM b. electron c. compound light d. SEM 3. The type of microscope that focuses beams of electrons on specimens is the 22 a. compoundb. electronc. scanning d. compound light