Unit 1: The Nature of Life

What is science? (1-1) an organized way of using evidence to learn about the natural world It also refers to the body of knowledge that scientists have accumulated over time. It is not based on belief or faith, magic, or legend but on actual evidence. It is concerned with the natural world, not the supernatural world.

Important Skills used When Doing Science: Observing- process of gathering information using your senses in a careful, orderly way Inferencing- making a logical interpretation based on prior knowledge or experience

How is Science Done? (1-2) Scientists use the scientific method. When scientists have a question about something in the world they use this method to find an answer: State the Problem or Question Gather Information (Research) Form a hypothesis Design / Perform the experiment Record / Analyze the Data Conclusion or Summary Repeat the Experiment / Communicate Results

What is a Hypothesis? A hypothesis is a possible explanation for a set of observations or possible answer to a scientific explanation. A hypothesis MUST be testable Proper hypothesis is written in an If, then statement

A Controlled Experiment Control Group: Part of your experiment that is not varied in anyway. You can compare your test groups to this set standard group. Independent variable (manipulated variable)- The change/difference you make in the experiment (the thing you are testing). Dependent variable (responding variable)- The differences that result from the experiment, the resulting effect. Constants- Things in the experiment that do not change, kept exactly the same for each test group so they do not affect the results.

Example: Tomatoes Question: Will adding fertilizer to the soil in my garden help me grow more tomatoes? Research: What other factors may affect the growth of my tomato plants? Hypothesis: Develop a hypothesis using and If, then statement

Experiment What are the constants in this experiment? Garden 1 Brand A tomato seed Water three times a day for 15 minutes Similar type of soil Try to control pests Doesn’t receive fertilizer Garden 2 Brand A tomato seed Water three times a day for 15 minutes Similar type of soil Try to control pests Receives fertilizer What are the constants in this experiment?

Which Garden is the Control Group? What is the Independent variable/Manipulated variable? (the factor that differs among the test groups) What is the Dependent variable/Responding variable? (the measurable change that results from changing the independent variable) What is the conclusion of the experiment?

Theories, Principles and Laws When a certain hypothesis has been tested repeatedly by many scientists throughout time and is continually supported that hypothesis is then referred to as a Theory The terms Principle and Law are also used to describe concepts that have stood the test of time and seem to remain true. Principles and Laws however, are typically not things that have been supported through experimentation

Learning Checkpoint What is inferencing? What are the steps of the scientific method? In which step would you find charts and graphs? What is the difference between an manipulated variable and a responding variable? What is the purpose of a control group? What does it mean to have a controlled experiment?

So Biology is the study of Life! What is Biology? “Bio” means Life “ology” means study of So Biology is the study of Life!

The Characteristics of Life Reproduce Made of Cells The Characteristics of Life Obtain and Use Materials and Energy Based on a Universal Genetic Code Change over time Grow and Develop Maintain a stable internal environment Respond to their Environment

Studying Life in Various Ways Branches of Biology Because there is such a variety of life Biology is divided into fields based on the type of life or particular perspective Examples of type of life: Zoologist study animals, Botanist study plants, Microbiologists study bacteria and other small organisms Examples of perspective: Paleontologists study ancient life, Embryologists study newly forming life

Studying Life at Various Levels The Molecular Level The Organism Level The Ecology Level

Tools and Procedures used in Biology (1-4) Science ALWAYS uses the METRIC SYSTEM to make measurements Why? Base units: Length- meter Mass- gram Volume- liter Temp. Celsius *We will focus on the proper use of various Biological tools and techniques as the year progresses.

Major Biological Themes Science is a Process Life evolves MAJOR THEMES There is interdependence in nature Structure fits Function Regulation (Homeostasis) Energy is transferred and transformed Continuity and Change Science, Technology and Society

Learning Checkpoint What are the 8 characteristics of life? What is the difference between a community and a population? What metric units would you use to measure the amount of water in a pool? Your height? Your weight? The weight of a paper clip?

Carl Linnaeus Naming System

Binomial Nomenclature Two name naming system Genus species or if written by hand Genus species Felis catus Canis lupus Canis lupus familiaris What are the rules for naming?

What is the Classification order? K P C O F G S ingdom hylum lass rder amily enus pecies … sometimes there is also a sub species

What goes away at each level?

We are…

Learning Checkpoint What is binomial nomenclature? What are the rules for scientifically naming animals? What kingdom are humans, dogs and spiders part of? What is the level after Order?

We all need to regulate ourselves to live… Homeostasis is … The tendency of an organism or a cell to regulate its internal conditions. This stabilizes the health and functioning, regardless of the outside changing conditions. Example? Body temperature

We all need to regulate ourselves to live… Thermoregulation is … the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different.

We all need to regulate ourselves to live… How do we get keep ourselves from overheating? Vasodilation is the widening of blood vessels. It results from relaxation of smooth muscle cells within the vessel walls.

We all need to regulate ourselves to live… How do we keep ourselves from getting too cold? Vasoconstriction is the narrowing of blood vessels. It results from relaxation of smooth muscle cells within the vessel walls.

Learning Checkpoint How do you maintain homeostasis? What type of external temperature causes Vasodilation? What type of external temperature causes Vasoconstriction? Why is it important for us to be able to regulate our body temperature?

We all need to reproduce to continue life… What are the 2 types of reproduction? Sexual reproduction Asexual reproduction

We all need to reproduce to continue life…