1. Biology I Chapter 1 Notes The Study of Life

2. Section 1: Intro to Biology The Science of Life BIO = life BIO = life LOGOS = study LOGOS = study Biology is the study of all living things (organisms, or the science of life) -When people study living things or pose questions about how living things interact with the environment, they are learning about biology. Biology is the study of all living things (organisms, or the science of life) -When people study living things or pose questions about how living things interact with the environment, they are learning about biology.

3. What do biologists “do”? Study the diversity of life – –Jane Goodall learning about chimps, now we can protect them… Research diseases – –From Goodall’s work, Mary King studied chimp DNA to better understand breast cancer Develop technologies – –Bionic “parts” or artificial limbs, medicine, treatments Improve agriculture – –Genetic engineering to allow plants to grow in nutrient poor soil or withstand disease; increase production Preserve the environment – –Prevent extinction of animals and plants (captivity programs) 5

4. Characteristics of Life 1. Made of CELLS: unicellular / multi-cellular 2. Are ORGANIZED 3. GROW and DEVELOP 4. REPRODUCE: ”Like produces like” -Sexual vs. Asexual Reproduction 5. RESPOND to stimuli: either internal or external 6. Require ENERGY 7. Maintain HOMEOSTASIS 8. ADAPTATIONS/EVOLVE over time -occurs in populations, NOT individual organisms Characteristics of Life

5. Section 2: The Nature of Science What is science?  Science: the body of knowledge based on the study of nature (biology, chemistry, physics, Earth science)  In science class we will: Rely on evidence Expand scientific knowledge Challenge accepted theories Question results Test Claims Use peer review Use the metric system: units with divisions that are powers of ten (International System of Units = SI)  (meter = length, gram = mass, liter = volume, second = time)

6. Characteristics of a “Good” Scientist (OSCO) 1. Observant 2. Skeptical 3. Curious 4. Open-Minded

7. How curious are you??? You throw away the outside and cook the inside. Then you eat the outside and throw away the inside. What did you eat? –ANSWER: an ear of corn What goes around the world but stays in a corner? –ANSWER: a stamp Give me food, and I will live; give me water, and I will die. What am I? –ANSWER: a fire I'm where yesterday follows today, and tomorrow's in the middle. What am I? –ANSWER: a dictionary I have hands that wave at you, though I never say goodbye. It's cool for you to be with me, especially when I say, "HI.“ What am I? –ANSWER: a fan

8. Observations lead to questions… how are they answered? Science follows a process (AKA scientific method): 1. 1.Ask a Question/Define the Problem – –Observations: collected with your senses – –Inferences: made with your mind, explain observations – –Observations/Inferences VideoObservations/Inferences Video 2. 2.Collect Data/Background information 3. 3.Form a VALID hypothesis – –Must make a prediction; must be testable – –Must be stated in the “If … then…” format Section 3: Methods of Science

9. 4. 4.Collect the Data using a Controlled Experiment The “independent” variable; the factor that changes; only 1 at a time The “dependent” variable(s) must be collected as data Quantitative Data: There are 3 mL of fluid; numeric Qualitative Data: The fluid is orange; word description 5. 5.Analyze Data – –Graphs (bar or line), Tables, and Charts (pie) 6. 6.Report or Form Conclusions Section 3: Methods of Science – Cont. NAMETIMEFrank 33 sec Jessica 27 sec

10. Tools of a Biologist: The Microscope Compound Light Microscope – –uses light reflected by two or more lenses – –1 eyepiece, 1 light (light goes through) Stereoscope (AKA Dissecting Microscope) – –2 eyepieces, 3 light combos (3-D objects) Electron Microscope – –Uses electrons reflected by magnets – –Can only be used with non-living specimens

11. 2 Types of Electron Microscopes A. Scanning Electron Microscope (SEM) electrons bounce off specimen produces 3-D image lower magnification than TEM B. Transmission Electron Microscope (TEM) electrons travel through the specimen higher magnification than SEM no 3-D image specimen must be frozen, embedded in plastic, and sliced into a thin piece Structure and Function of the Electron Microscope

12. Microscope Vocabulary  Total Magnification Calculated by multiplying ocular magnification by objective magnification  Field of view What you see when looking in the eyepiece Gets smaller when you increase magnification  Working Distance Distance between objectives and stage Gets smaller when you use the high power objectives  Depth-of-field Occurs when you are looking closely at the layers of a specimen, you can actually see different layers at the same time!

13. Stereoscope vs. Compound Light Microscope Eyepieces (2 vs. 1): 2 eyepieces allow for a 3-D image Lights (2 vs. 1): 2 lights allow you to see solid objects Size of Object: Larger working distances allows you to see bigger things

14. Think about this... Do mice come from straw? Do mice come from straw? Do frogs come from mud? Do frogs come from mud? Do maggots come from meat? Do maggots come from meat? If you answered no to any of the above questions in the 1600's, people would think you were crazy. These things were all considered to be true facts until the year 1668. If you answered no to any of the above questions in the 1600's, people would think you were crazy. These things were all considered to be true facts until the year 1668. Spontaneous Generation: AKA “abiogenesis” Spontaneous Generation: AKA “abiogenesis” –Living organisms are generated by decaying organic substances –EX: mice spontaneously appear in stored grain or maggots spontaneously appear in meat 10

15. Redi’s Controlled Experiment OBSERVATIONS: Flies land on meat that is left uncovered. Later, maggots appear on the meat. HYPOTHESIS: If flies land on meat, then maggots will be produced. PROCEDURE Controlled variables: jars, type of meat, location, temperature, time Manipulated Variable: gauze covering that keeps flies away from meat Uncovered jarsCovered jars Several days pass Maggots appearNo maggots appear Responding Variable: whether maggots appear CONCLUSION: Maggots form only when flies come in contact with meat. Spontaneous generation of maggots did not occur. Section 1- 2 Go to Section:

16. HYPOTHESIS – –Possible explanation – –Educated guess THEORY – –Explanation that has been tested and not yet disproved – –EX: Theory of Evolution, Theory of Relativity LAW – –Statement about nature that is ALWAYS TRUE – –EX: Law of Biogenesis, Laws of Gravity Review of terminology

17. Levels of Organization in Living Things Molecules↓Cells↓Tissues↓Organs↓Systems↓Organisms↓Populations↓Communities↓Ecosystems↓Biosphere