1. Observation, Inference, Measurements and Graphing

2. What are observations and inferences?
Observation – an interaction of the senses with the environment.
Instruments are used in science to enhance observations.
Examples include:
Telescope
Balance
Microscope

3. What are observations and inferences?
Inference – an interpretation of observations.
It is a hypothesis (an educated guess).

4. Determine which statements are observations and which are inferences
1. The cat has two wooden legs
2. The cat tried to eat the piranha.
3. The bird is in a cage.
4. The piranha ate the cat’s legs.
5. The bird and cat are for sale at the pet shop.

5. What is Classification?
Classification – Grouping objects and events based on observable properties.

6. Measurements and Instruments
Measurement – A description of observations using numbers.
Instrument – A tool that improves the ability to make observations.
Examples:
Ruler
Clock
Graduated cylinder
Triple beam balance

7. Instruments Instrument Measurement Units Ruler
Distance (between two points) cm
Area (l x w)
Volume (l x w x h)
cm2
cm3
Graduated Cylinder
Volume
ml (cm3)

8. Instruments Instrument Measurement Units Clock Time Balance Mass
Seconds
Minutes
Hours
Days
Years
Balance
Mass
Grams (g)

9. Using a Ruler cm
What is the unit of measure for this ruler (large tick marks)?
Centimeter (cm)
What is the unit for the small tick marks on the ruler?
Millimeter (mm)
How many millimeters are there between each centimeter?
10 mm are between each cm
Draw a line above the rule from 0 to 1 cm, and draw another line from 20 to 25 mm.

10. gram (g) meter (m) liter (L)
The Metric System
In the scientific community, we use the metric system. We need to be able to convert from one unit to the other.
King (Kilo)
x 1000
Henry’s (Hecto)
x 100
Milk (milli)
x 1/1000
Daughter (Deca)
x 10
Usually (unit)
1.0
gram (g) meter (m) liter (L)
Drinks (deci)
x 1/10
Chocolate (centi)
x 1/100
To convert to a larger unit, move the decimal point to the left (or divide)
To convert to a smaller unit, move the decimal point to the right (or multiply)
The Ladder Method

11. Metric Conversions Convert the following using the Ladder Method:
3 Kg = ___________ g
250 mm = _______ cm
.4 L = _________ ml
600 cm = ________ m
800 m = ________ Km
72 ml = ________ cl

12. Common Measurements in Biology
Mass – The amount of matter in an object.
Mass is expressed in grams (g)
Mass is measured using a triple beam balance.

13. Common Measurements in Biology
Volume – The amount of space an object takes up.
Volume is expressed in Liters (l) or cubic centimeters (cm3).
Volume is measured using a ruler or a graduated cylinder.