Lab 1 – The Scientific Method and Termite Trails

Welcome to NSB

• Why do you need to know about Biology?

– Stem cells, cloning, DNA, genetic testing, vaccines, evolution, bioethics, animal and plant diversity, mutations, antibiotic resistance, viruses, diseases, global warming, energy, fossil fuels, genetically engineered foods.

– These things affect you EVERY DAY. You want to

be informed, so you can make smart choices.

Why do I need to take a lab?

• We know you aren’t looking to be a scientist • But you will have experiences that involve

science EVERY DAY. • Labs provide a hands-on, active approach to

learning. • Labs demonstrate The Scientific Method. • Labs show how simple research can affect the

way you approach problems.

Natural Science Syllabus

• Grading • Quizzes • Attendance • Participation • Paper/Presentation • Code of Conduct • Electronic Communications

Lab Manual

• Must be purchased for lab. Available in Bookstore.

• Needed every week to turn in your questions. This is how you get your participation points.

In the lab - Lab Equipment

• Always check to make sure you have all the needed equipment before you begin your lab.

• Lab equipment must always be stored

properly and cleaned to avoid contamination. Never put away equipment that is dirty.

Safety Procedures 1. Never conduct any

laboratory experiments until proper instructions have been given and a instructor is present.

2. If something goes wrong while performing a laboratory experiment, immediately get the attention of the instructor.

3. Always read the instructions and safety precautions before beginning an experiment.

Designing an Experiment

• Each of the NSB Labs has been designed to give you a “big picture” view of Biology.

• Each lab has the same format – a short lecture, background information, materials, the procedure, collecting data, and questions designed to assess your understanding.

• Each lab follows the messy cycle called “The Scientific Method”

The Scientific Method starts, stops, moves forward, moves backward, and

rarely just follows the circle.

Much of what we do in science DOES NOT involve experiments

• Much of science is making observations and descriptions. – Different sizes – Different colors – Different structures – Different functions

– Then, we make predictions about WHY things

might be different

Forming a Hypothesis

• Forming a hypothesis first involves observation.

• Then, ask a question about something you observe. Your hypothesis will be a possible answer to that question.

• Remember a hypothesis does not have to be correct; it simply has to be testable.

• In fact, often hypotheses are wrong. However, even a wrong hypothesis is useful because it helps you rule out ideas.

Testing a Hypothesis

• You must design a controlled experiment to test a hypothesis. A controlled experiment tests only one factor at a time.

Dependent v. Independent Variable

• Independent Variable – Changed – The one factor that YOU alter between experimental

groups

• Dependent Variable– Measured – Your result (data), (depends on what is changed)

Data Collection Techniques • All of the information collected during a

scientific investigation is known as data. Data can be collected through the following techniques: Quantitative measurement – numbers such as weight, volume, or how many legs

• Qualitative observation – colors, size, shape, feeling

Analyzing Data

• Data can be analyzed by making inferences from and recognizing patterns in the data. You might use the following methods to analyze your data: – statistical analysis

– creating graphs

– organizing data into tables and charts

Data Collection and Sample Size

• The larger the amount of data collected,

• The larger the sample size,

• The more times the experiment is repeated,

• The more valid the results.

Collect and Interpret Data • Precision in Data Collection

– When you collect data you need to be concerned about precision and accuracy. Precision refers to how consistent and reproducible a measurement is. A good rule of thumb is to take measurements two or three times (called replicates) in order to ensure precision

• Accuracy in Data Collection – Accuracy refers to the correctness of a

measurement. Data will be useless unless it is collected accurately.

Precision vs. Accuracy

• Which piece of equipment would be best for accurately measuring 76 ml?

Do I have a theory, or do I have a hypothesis?

• Scientists use the word “theory” differently than the general public.

• “A scientific theory is a set of principles that explain and predict phenomena. Scientists create scientific theories with the scientific method, when they are originally proposed as hypotheses and tested for accuracy through observations and experiments. Once a hypothesis is verified, it becomes a theory.”

What’s YOUR hypothesis?

• The termites used in this experiment are a group of social insects usually classified at the taxonomic rank of order Isoptera. As truly social animals, they are termed eusocial .

• Eusocial animals display several characteristics – they have a queen, workers or laborers, defenders, colonies, castes – but WHY????

How to “do” the lab

• Read the background information • Look at your materials and procedure – what

are you going to do, and WHY? • Follow directions, and fill in your data sheet

for Lab 1. • Make sure your full, real name, section, and

TA are on the handout, and turn it in. • You aren’t finished until your lab station is

clean and ready for the next class.