What is science?

Knowledge! “Science” comes from a latin root word

that means Knowledge! It’s a system that builds and organizes

knowledge about the universe in the form of testable explanations and predictions about the universe.

Science Scientific thought involves making

observations, using evidence to draw conclusions, being skeptical about ideas and being open to changing them when new discoveries are made.

Universal Laws Science helps to discover truths that apply

to everything. These truths are called universal laws.

Why do I have to study science? Understanding science can help you stay

healthy. It can help you to be a wiser consumer

(not get ripped off). It can help you be a better-informed

citizen.

How does science work?

Science is a process. It does not have a set order, but there are

several regular steps to the process.

Observe Almost all scientific investigations occur

with an observation. The easiest observations are made about

things that can be seen, or counted. “One of my posters has fallen off the wall” is an easy

observation to make. But how do we observe things like bacteria,

cells, or even atoms and electrons?

Qualitative/Quantitative Observations have 2 categories.

Qualitative observations are made without using measurements or numbers.

“That flower is blue” Quantitative observations are made using

numericals measurements. “The plants have grown 5 cm” “There are more deer in Georgia today than 20

years ago”.

Hypothesis A hypothesis is a possible explanation for

an observation. They can be tested by experimentation. They are not guesses. A hypothesis needs to

be based on fact or stem from prior knowledge or observations.

“My poster has fallen because the there wasn’t enough tape on it!”

Experiment An experiment is a procedure that is

carried out under controlled conditions to test a hypothesis. Control group: Receives no treatment and

serves as a standard of comparison. Experimental group: Identical to the control

except for a single variable.

Variables Variables are things that change during an

experiment. Independent variables are changed by the

scientist. Dependent variables are measured over the

course of the experiment.

Several identical hydrangea plants, each with soil of a different pH

pH 3 pH 5 pH 7 pH 9 pH 11Monitor the color of flowers over a period of several weeks or months

Sci. method steps continued Analyze data Publish results (results should be

repeatable) Form a theory (possibly) A theory is a generally accepted scientific

principle

An experiment was performed to determine the effect of music on ivy plants. Two groups of plants were set up. One received music 24 hours/day, and the other was left in silence. All plants were given equal light, water and minerals.

a) Independent variable?b) Dependent variable?c) Constant factors?d) Control group?e) Experimental group?f) Qualitative observations?g) Quantitative observations?

Radon is a radioactive gas that seeps into homes from the soil. It is thought to be one of the leading causes of lung cancer. A research team investigated this problem by collecting data from

50 homes. They measured basement radon levels, and noted how many people living in the homes had lung cancer.

a) Independent variable?b) Dependent variable?c) Control group?d) Experimental group?e) Is a placebo needed?f) Possible problems with the study?

A man states that he saw Bigfoot in an isolated forest. He was alone and did not take any pictures or collect any physical evidence of Bigfoot. His observation is not very scientific because it:

a) Did not have any measurementsb) Did not have a hypothesisc) Was not made by a scientistd) Was not repeatable