Unit 1 The Basics of Biology

Goals of All Science Investigate and Understand the natural world Explain what happens in the natural world Predict what is going to happen in the natural world

How Scientists Think Scientists gather information (DATA) by making observations. Two types of data: Quantitative Data- Information that describes a quantity that can be measured and described with numbers. -Example: 5 mm long, 12 pounds, 16 eggs  Qualitative Data- Information that describes a quality that cannot be described in numbers. -Example: red truck, sour taste, fruity smell

Self-Check: Make one Quantitative observation and 2 Qualitative observations about this picture

What Do We Do With the Information We have Gathered? Inference- a logical interpretation based on prior knowledge or experience.

Self Check- make an inference about this picture

Each of these blood samples is from a different person. Blood sample #29 tested positive for malaria. What can the doctors infer?

The Scientific Method 1. Ask a Question 2. Form a Hypothesis 3. Set up a controlled experiment. 4. Record and analyze your results. 5. Draw a conclusion 6. Repeat and publish results

Example: Francesco Redi’s spontaneous generation experiment follows the scientific method

1) Ask A Question Is Spontaneous Generation how maggots form?

2) Form a Hypothesis A proposed scientific explanation for a set of observations Hypothesis- If flies land on a piece of meat, then maggots will appear

3) Setting Up a Controlled Experiment  Different factors that may change and affect the outcome of the experiment are variables.  Examples: Independent and Dependent Variables

What Are Our Variables? Independent Variable: Dependent Variable: Controlled Variables:

4) Recording and Analyzing Results All experiments should be carefully documented so that another person can duplicate (repeat) them. Ways to Document Observations & Data: - Written Notebook - Computer -Drawings

5) Drawing A Conclusion Does the data support or disprove the hypothesis?

6) Repeat and Publish Your results need to be repeated many times, by many scientists until they are considered trustworthy

What are the Independent, Dependent, and Controlled variables in the following experiment?

Louis Pasteur finally shows that spontaneous generation does not occur Microorganisms Present No Microorganisms Present WHY? Pasteurization

Experimental and Control Groups Experimental Group – The subjects or items exposed to the manipulated variable. Control Group - The subjects or items not exposed to the manipulated variable. Used as a comparison to the Experimental group.

What Do We Do If An Experiment Is Not Possible? Scientists must study these conditions as they occur in the world. As many variables as possible must be controlled.

A Theory After a hypothesis is well tested by many scientists and never proven to be false it becomes a theory.

1-3 Studying Life What makes something living? Are these things alive?

8 Characteristics of ALL living things Made up of Cells Reproduce Based on a universal Genetic Code Grow & Develop Obtain and use Materials and Energy Respond to their environment Maintain a Stable Internal environment Change over time

Made Up of Cells Cells are the building blocks of living things. Cell- A collection of living matter enclosed by a barrier. Unicellular: made of one cell Multicellular: made of many cells

Reproduction All organisms make more organisms of the same species.

Reproduction: Two Types Sexual Reproduction Cells from two parents produce an offspring. Asexual Reproduction A single parent produces an offspring by itself.

Based on a Genetic Code The traits of all living things are determined by it’s DNA. This DNA is the same type of molecule in all living things.

Growth and Development All organisms get larger. (Growth) Organisms go through stages of growth and change. (Development)

Need for Materials and Energy The process of building or breaking down molecules for energy is metabolism All living things need energy. Plants- Get energy from the sun. Most other organisms- get energy from food.

Respond to Environment Organisms detect and respond to stimuli from their environment. Stimulus- a signal to which an organism responds.

Maintain Internal Balance Homeostasis-The process that organisms use to control their internal environment. Temperature, salt concentrations, amount of water.

Living Populations Evolve Individual organisms DO NOT evolve by themselves. Species change over time.

1-4 The Tools of Science The Metric System Who Uses the metric system? Why do all scientists use the metric system? Liberia Burma

The Metric System Start  Move Decimal to the Right  KiloHectoDeka Grams Liters Meters DeciCentiMilli  Move Decimal to the Left  Start King HenryDied By (Base Units)Drinking Chocolate Milk

Line Graphs Where is the X axis? Where is the Y axis? Is the speed at 3 seconds higher or lower than at 0 seconds? Is speed increasing or decreasing over time?

Line Graphs

Bar Graphs -Which category is on the X axis? -Which category is on the Y axis? -Which Brain Region has the most receptor binding? -Which has the least receptor binding?

Bar Graphs

Pie Charts Where will most of our biofuel come from in the future? How much will corn contribute to biofuel production?

What does this graph tell us?