Unit A: Introduction to Biology and Scientific Methods

A. Affixes and RootsB. Scientific MethodsC. Characteristics of living things

Part 1: Affixes and Roots

• Identify the meaning of words using affixes

How am I suppose to understand all these big biology words?

• Affixes = prefixes and suffixes• Prefixes are added to the beginning of a word• Suffixes are added to the end of a word• Roots are the foundation of a word. By familiarizing yourself with just a few of

these you can determine the meanings of many biology terms.

Affixes and Rootsa Without/not

anti against

bi / di two

bio life

chlor light green

meso middle

cide kill

Cyto cell

genesis to originate

homo/homeo same

hetero different

logy study of

macro large

micro small

auto self

chromo color

multi many

pro before

uni one

zoo animal

zygous two joined

aero air

aqua water

Terra/e land

derm skinEcto outerEndo innerEpi Highest/above

Hemo bloodHyper abovehypo below

Summary Questions Part 1: Derive the meaning

1. biology

2. zoology

3. unicellular

4. homozygous

5.antacid

6. microbiology

Part 2 – Scientific Method

• Lab Report• Independent vs. Dependent Variables• Experiment vs. Control groups• SI

What are scientific methods?

• The common steps that biologists and other scientists use to gather information and answer questions

The five basic steps

1. Identify a problem.

2. Formulate a hypothesis

3. Design an experiment.

4. Analyze the results.

5. Draw conclusions.

Identify a problem.• Any question that can be explored scientifically

via observations or experimentation is valid.

Formulate a hypothesis.

• A hypothesis is an explanation for a problem or a question that can be tested.

• It’s your best guess as to what the results of an experiment are going to be.

Design an experiment.• independent variable: what the scientist changes. • dependent variable: what the scientist measures.

• control group: receives no experimental treatment.

• experimental group: receives experimental treatment.

Analyze results.

• Look at data tables created during the experiment. Make graphs out of them to better understand what is going on.

Draw conclusions.

• Decide why you think the results were what they were.

• Example: Paper towel brand X was thicker and 2-ply, hence the greater cost to produce and also the greater amount of material to absorb water.

SI (metric units)

Length = meters (m)

Volume = liters (L)

Mass = grams (g)

Unit Metric equivalent

Examples

Meter 1m A little more than a yard

Kilometer 1,000m About 2/3 of a mile

centimeter 0.01m Radius of a penny

millimeter 0.001m Width of a pencil tip

liter 1L ½ a pop bottle

milliliter 0.001L About 15 drops of water

Part 3 – Characteristics of Living Things

• Identify the 5 characteristics of life• Compare stimulus to response• Define homeostasis• Describe the differences between Type I

and II diabetes

What Is biology?

• Biology is the study of life.• This, of course, leads to the question…

What is life?

• After observing organisms, or living things, scientists created a list of characteristics that all living things have in common.

All living things…

have internal organization & are made of cells

unicellularmulticellular

reproduce. make babies.

grow. get bigger.

respond to their environment. react.

maintain homeostasis. keep an internal balance.

metabolize energy eat or make food.

adapt to their environment. evolve.

All living things are composed of one or more cells.

• The four amoebas (top) and the euglena (bottom), are each made up of just one cell each.

• Do they meet this first requirement of living things?

All living things reproduce.

• To reproduce, or make more copies of oneself, can be done sexually. For example, when two giant pandas mate, a baby panda bear can be created.

All living things reproduce.

• Reproduction can also occur asexually (without sex), as in the case of this cell which is splitting into two separate cells.

All living things grow.

• Some living things not only grow larger, but undergo drastic physical changes.

• The five images are all of the same insect in different stages of life.

All living things respond to their environment.

• A Stimulus (cause) = triggers a response (effect)

• Dr. Pavlov rang a bell whenever he served his dogs food. As a result the dogs would drool every time they heard a bell; food or no food. What was the stimulus? What was the response?

Dr. Pavlov gets treated.

Years later one of the dogs sought therapy.

All living things maintain homeostasis.

• Homeostasis = stable internal body conditions and environment– Temperature, pH,

fluid/mineral content, etc

• Failure to maintain homeostasis usually leads to death

Diabetes• The body releases a

hormone called insulin from the pancreas to maintain blood glucose (sugar) levels

• Diabetes is a condition in which the body’s ability to maintain stable glucose levels is upset

Type I and II Diabetes

Type I Diabetes• Body is unable to

produce insulin• Usually diagnosed in

children• Genetic; not caused by

diet

Type II Diabetes• Cells in the body no

longer respond to insulin

• Usually occurs in adults• Caused by obesity and

sugar rich diets

All living things obtain and use energy.

• This cheetah will gain energy from eating this gazelle.

• What other examples of energy obtaining do you see?

All living things adapt to their environment.

• The figure on the right is not just of a tree branch. If you look closely there is an insect there known as the walking stick. How is it adapted to its environment?

All living things adapt to their environment

• How do a duck’s feet (top) differ from an owl’s feet (bottom)?

• How do these adaptations help each to survive?

Summary Questions1. What are the 7 characteristics of living

things?2. A person feels cold and he shivers as a result.

Identify the stimulus and the response.3. Define Homeostasis and provide 2 examples.4. Converting food into energy is known as: