Introduction to Life Science

PA State Standards

What is Life Science?

Life Science is the study of living organisms and their

environment.

Breakdown the word Biology into a prefix

and suffix

BIO –

OLOGY –

LIFE

STUDY OF

Therefore: Biology is the study of life

How many other ‘ologies can you come up with?

Here are a few examples:

Astrology – Study of…

The Stars

Ecology – Study of …

Living things and how they interact with their environment

ZOOLOGY – Study of …

Animals

Entomology – Study of …

INSECTS

What are the scientists called that work in the some of these fields?

Botanist – Studies plants

Microbiologist – studies microscopic organisms

Biochemist – Studies chemicals in life

You are a Scientist!

When you come in to this room, you must think like a scientist!

A scientist always needs to:

Question – Always question the world around you.

What? Why? Where? When? How?

A scientist always needs to:

Observe: You observe the world by using your five senses.

Sight

Taste

Hearing

Smell

Touch

There are TWO types of OBSERVATIONS:

QUALITATIVE

QUANTITATIVE

QUALITATIVESight

Taste

Hearing

Smell

Touch

This is what an object looks like, feels like, smells like, etc.

**For Example: How do you find the light switch in your room when it is dark?

QUANTITATIVE

The actual measurement of an object – How long is it? How much does it weigh?

What if you are not 100% sure about an

observation but need to answer a question?

For example: What might be wrong with the lake? OR What can you INFER about the lake?

NO

FISHING OR SWIMMING

NO

FISHING OR SWIMMING

What did you infer about the lake?

•Pollution

•Possible current

•Parasites

Infer –

Forming a conclusion based upon what you think explains an observation.

Example 2: I walked into my house and it smelled good.

You could infer:

•Cooking/baking

•Cleaning

•Candles burning

The Scientific Method Steps followed to

solve a problem.

1. State the problem

2. Gather information

3. Form Hypothesis

4. Experiment

5. Data

6. Conclusion

Scientific Method1. State the Problem

What might be his problem?

Scientific Method2. Gather Information

Use books, internet, magazines, talk to people, etc.

Scientific Method3. Form a Hypothesis

An educated prediction or explanation on how to solve your problem

Scientific Method4. Experiment

Test your hypothesis to solve your problem

Scientific Method5. Conclusion

An answer that explains the problem.

Experiments To solve a problem

or question, one must conduct an experiment.

There are two groups needed in an experiment.

The two groups needed are:

The Experimental Group

This is the group that is being experimented on.

It is the group that contains the variables (or the factor being tested)

The Control Group

This is the group that remains the same, and is not being experimented on.

What is a variable? It is the factor being tested: There are

two types

Independent variable

You can change or control this factor

Dependent variable This is the factor

being measured.

Let’s try an experiment and see if we can find the

two groups:

The County fair is coming up and you want to enter the plant contest; however, your plants at home are in sad shape. You decide to go to the Home Depot to buy the latest plant growth products, and try an experiment to see if they really work better than regular water and sunlight.

The County Fair Experiment

Plant A Plant B

We will take two plants that are alike. Plant A will get only sunlight and water. Plant B will get the same as plant A plus grow fast fertilizer.

Both plant A and plant B get equal amounts of sunlight and water.

ONLY Plant B receives the Fast Growth Fertilizer.

Plant A Plant B

Hypothesis: I believe plant B will grow at a faster rate than plant A.

The Data This is a graph

showing the growth of both plants over 4 weeks.

Which plant grew more?

Plant B grew at a faster rate than plant A.

05

10

15

20

25

30

35

40

WEEK

1

WEEK

4

plantA

plantB

Conclusions Our data agrees

with our hypothesis. Plant B grew at a

faster rate than plant A.

Plant B

What were the two groups in the experiment?

Experimental group

Plant B

Control Group

Plant A

In a real experiment, you will have a lot of subjects in each group. In this case, we would have had about 100 plants in each group.

What are the variables?Remember the experiment – 2 of the exact same plants were given sunlight & water, and only plant B was given fertilizer. We were trying to see which one grew faster.

Dependent Variable – What is being measured?

Growth of plants

Independent Variable – What did we change in one of the plants?

The fertilizer