Unit 1: Introduction to Biology 1a: Research, Measurement, and Graphing

Research Two main types: Quantitative Descriptive (aka Qualitative) Uses controlled experiments Results are numerical data Descriptive (aka Qualitative) Relies on observations of situations out of scientist’s control Results are descriptions of observations Often an important tool for wildlife studies

Quantitative Research Data analyzed by comparing the numerical values Tables Graphs Measurements are made using the International System of Measurement (SI) Based upon the metric system Understandable to scientists around the world

Effects of Fertilizer on Plant Height Tables All tables must include: Descriptive Title Labeled columns and rows Labeled units Should show relationship between independent & dependent variable In a report, a reader should be able to understand a table without referring to the text Effects of Fertilizer on Plant Height Amount of Plant Fertilizer (g) Independent Height of Plant (cm) Dependent 2 12 6 20 10 4

*DRY MIX Graphs All graphs must include (TAILS): Title y-axis x-axis y-axis All graphs must include (TAILS): Title Descriptive, should include independent & dependent variable Axes- labeled with (units) *DRY MIX* Intervals Each increases by an equal amount; clearly numbered Legend (key) Scales on each axis Min should be slightly lower than smallest value, the max slightly greater than largest Choose intervals that allow you to use entire graph *DRY MIX * Independent (manipulated) on x-axis * Dependent (responding) on y-axis Dependent responding y axis Manipulated independent x axis

What type of graph should I use? Line For continuous quantitative data Ex. Height of plant over time Line graph relationships Direct variation – one variable increases as the other increases Inverse variation – one variable decreases as the other increases Direct= linear Inverse= hyperbola

What type of graph should I use? Bar For non-continuous data (usually in categories) Pie For data that are parts of a whole

International System of Measurement (SI) Basic units of measurement Length – meter (m) Tool – ruler or meter stick Volume – liter (L) Tool – graduated cylinder Mass – kilogram (kg) Tool – balance Time – second (s) Tool - stopwatch Temperature – Kelvin (K) [We will most often use Celsius (°C)] Tool - thermometer

Units of Measurement Metric system – based on the power of 10 kilo (k) – 1 kilometer(km)= 1000 meters hecto (h) – 1 hectometer (hm)= 100 meters deca (da) – 1 decameters (dam)= 10 meters Base unit (m, L, g) deci (d) – decimeter (dm)= 0.1 meter centi (c) – centimeter (cm) 0.01 meter milli (m) – millimeter (mm) 0.001 meter

Converting one metric unit to another k h da Basic unit d c m (m, L, g) To convert from one unit to another, move the decimal same direction and number of places the units are from each other 12 kilometers is __ centimeters centimeters are 5 places to the right 1,200,000 cm 134 decigrams is __ hectograms hectograms are 3 places to the left 0.134 hg

Unit 1: Introduction to Biology 1b: Scientific Investigation & Science versus Technology

Methods of Biology The series of steps used by scientists to gather information and answer questions is called the Scientific Method. The Big Bang Theory- Scientific Method

7 Steps of the Scientific Method Number 1 - State the Problem/Question

7 Steps of the Scientific Method Number 2 – Background Research Information gathered should be: Credible Accurate Relevant These sources could be: Previous scientific investigations Science journals Textbooks Other credible sources, such as scientifically reliable internet sites.

7 Steps of the Scientific Method Number 3 - Form a Hypothesis testable explanation “If…then…because…”

7 Steps of the Scientific Method Number 4 – Design and Conduct Experiment The experiment will have two groups: Control Group – all conditions are kept the same Experimental Group – same as control except for the one factor being tested

7 Steps of the Scientific Method An important part in the experimental design is the sample size – the number of test subjects A large sample size increases the reliability of results A large sample size decreases the effect of errors on the outcome Basically, the more people/subjects you test, the more reliable and accurate your data will be! Law of Large numbers….statistics….flipping a coin

7 Steps of the Scientific Method Variables Independent Variable- Condition that is changed in the experiment– it will be the only thing that can affect the outcome Dependent Variable- Outcome observed– it depends upon the changes made to the independent variable

Independent vs. Dependent Variables Mark the dependent and independent variable in each situation Suzy wanted to test how changing her diet affected her weight. The track team members that ran extra laps at practice ran better times at the next meet. Jack planted half of his roses in the shade and the other half in the direct sunlight and measured the differences in plant height and bloom production.

7 Steps of the Scientific Method Number 5 - Record and Analyze Data Data – information obtained from experiments Observations, Results Should be precise and accurate Precision – the degree to which measurements made in the same way agree with each other If you and I measure it, do we get the same thing? Accuracy – the degree to which the value measured agrees with the true or accepted value Even if we both got the same thing, did we measure it correctly? Analyze the data using graphs, charts, tables Using incorrect equipment could result in precise, but not very accurate data Ex. Using a 100 ml grad cylin to measure 5 ml of water or not zeroing out the scale.

7 Steps of the Scientific Method Number 6- Interpret the data and draw conclusions that serve as a starting point for a new hypothesis Scientists must use inferential reasoning to figure out answers to their questions based on evidence gathered through observations and from information that has already been discovered about the topic. Scientists understand the inferences are always subject to revision as new evidence becomes available

Observation vs. Inference Inference – making a judgment based upon an observation and past experience Example: Kids come inside wearing coats. They are holding umbrellas. Their shoes are wet. Inference: It’s raining. Observations: coat, umbrella, wet shoes

Make at least 3 observations about this picture. Make at least 3 inferences about this picture.

Make three observations and inferences with this new information

What does this final picture do to your previous inferences?

7 Steps of the Scientific Method Number 6 Continued- State a Conclusion Did the data support the hypothesis? If yes… Verify results Can the experiment be repeated? Do other scientists support the findings? If no… Repeat the experiment Revise the experiment Develop a new hypothesis (most experiments cycle from step 3 to 6 back to 3 again) Number 7 – Publish Results

7 Steps of the Scientific Method Fact – a truth known by actual experience or observation Ex. The hardness of iron, the number of ribs in a squirrels body Law- a logical relationship between 2 or more things that is based on a variety of facts; often mathematical Describes how nature behaves, does not explain why it behaves that way; ex. Force= mass x acceleration Theory – a well-supported explanation of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypotheses Explanation for why certain laws and facts exist; ex. Newton’s theory of gravity Truth, in science, is never final and what is accepted as fact today may be modified tomorrow Law- description of how nature behaves (also often mathematically defined) Theory- explains how nature works Facts supporting Newton’s theory- the behavior of planets, of projectiles, and apples

I wonder why the dog's wound doesn't become infected. A student noticed that when a dog is cut, the dog periodically licks its wounds. Usually after a few days, the wound begins to heal without ever showing signs of infection. The following steps outline the student's line of reasoning: I wonder why the dog's wound doesn't become infected. The dog's saliva must prevent the growth of infection-causing bacteria. I'll obtain a bacterial culture and grow the same kind of bacteria in two identical culture dishes. Once the bacteria start growing, I'll add dog saliva to only one of the dishes and leave the other alone. I'll cover both dishes. Then I'll observe what happens each day for a week. Even after adding the dog saliva to one of the dishes, the bacteria continued to grow in both dishes over the course of the week. However, the bacteria in the treated dish grew more slowly than the bacteria in the untreated dish. I think I'll try something else. I'll start with two identical culture dishes, as before, and use the same kind of bacteria in each dish, but this time I'll treat one dish with dog saliva before I add the bacteria. I'll observe what happens each day for a week. What was the student’s hypothesis? Which step described the experimental set up? Identify the control What is the independent variable? What is the dependent variable? What data did the student collect? What is a possible conclusion from this experiment?

Science and Society Ethics – moral principles and values held by humans What role do ethics play in scientific research and results? Can science answer all questions? Technology – application of scientific research to address society’s needs Can technology solve all problems?

Scientific Investigation vs Technological Design Goal is to describe, explain, and predict relationships that occur naturally Technological Design – process followed to design products or processes to meet specific needs Goal is to create a specific outcome, perhaps advance the standard of living in societies Scientist- Attempts to explain how different fuels affect pollution Technologist- Attempts to develop ways to lower pollution SI- explaining relationships TD- changing relationship that exists to achieve desirable results

Scientific Investigation vs Technological Design Identifies a problem – asks a question Identifies a problem or need Researches related information Designs an investigation or experiment Designs a process or a product Conducts the investigation or experiment – repeated trials Implements the design or the process – repeated testing Analyzes the results Evaluates the conclusion – did the results refute or verify the hypothesis Evaluates the process or product – did it meet the criteria Communicates the findings Communicates the product or process

Unit 1: Introduction to Biology 1c: Biology & the Characteristics of Life

What kind of things would a Biologist study? What is Biology? The study of life What kind of things would a Biologist study? Characteristics of known and new living things Interactions between living things Interactions between living things and the environment Problems living things face and possible solutions

Organisms possess all characteristics of life Organisms possess all characteristics of life. Which of these is not alive? http://en.wikipedia.org/wiki/Bacteria

5 Characteristics of Living Things #1 Living things are Organized All living things are made up of cells the parts that make up the organism are arranged in an orderly structure Levels of Organization

Atoms Molecules Organelles Cells Tissues Organs System Organism Population Communities Ecosystems

Characteristics of Living Things: #2 Living things Reproduce organisms produce offspring for the survival of the species species: group of organisms that can interbreed and produce fertile offspring

Characteristics of Living Things : #3 Living things Grow & Develop Growth: increase in the amount of living material and the formation of new structures Start as single cells and become more complex Changes throughout life are known as development Growth- increase in size or number Develop- learn…increase ones ability…maturing

Characteristics of Living Things : #4 Living things Respond to their surroundings Conditions in the environment can cause a reaction by the organism. Stimulus  Response Why respond? To Survive! Homeostasis: Regulating internal conditions suitable for survival Water, temperature, nutrients Environment- living and nonliving thing around organism Organism respond intentionally as well as automaticaly….we shiver when cold because our brain monitors our temp very closely…get too cold and it sends message to muscles to begin contracting and expanding in quick bursts…produces heat and tells us we need to get inside

Characteristics of Living Things: #4 cont. Responding to surroundings requires Energy! Energy – ability to do work Living things must be able to convert resources from the environment into building blocks so it can maintain and build itself Metabolism- the sum of the chemical reactions that take place within a living organism and that provide energy for vital processes

Characteristics of Living Things: #5 Living things Adapt and Evolve Organisms develop structures, behaviors, and internal processes to help them respond to their environment – adaptations Living things can pass traits from parent to offspring (heredity) The gradual accumulation of these adaptations is evolution

5 Characteristics of Living Things What kind of adaptations have these organisms developed? Camo Critters

Which characteristics of life are represented? Characteristics of Living Things http://www.microscopy-uk.org.uk/mag/indexmag.html?http://www.microscopy-uk.org.uk/mag/artsep01/amoeba.html