Observation, Inference, Measurements and Graphing

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

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

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.

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

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

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)

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

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.

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

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

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.

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.