1. Chapter 1 Sect 1- 4 Reference: Modern Biology Pgs. 21 - 24

3. Scientific tools and techniques enable Biologists to probe deeper into the secretes of life Scientific tools and techniques enable Biologists to probe deeper into the secretes of life BIG IDEA

4. One of the most widely used tools in Biology is the Microscope. WHAT DOES A MICROSCOPE DO? Enlarges an image as well as shows detail. Magnification-the amount an object’s size is increased Resolution-the power to show details clearly Microscopes vary in powers of magnification and resolution. TOOLS OF THE TRADE: MICROSCOPES

5. *Compound Light Microscope A Compound microscope has a series of lenses to collect and focus the light transmitted through the specimen mglass slide A Compound microscope has a series of lenses to collect and focus the light transmitted through the specimen m ounted on a glass slide Must be thinly sliced or very small lenses Pair of lenses o Ocular o Ocular lens (eye piece) o Objective o Objective lens (nose piece) Magnification Magnification determined by multiplying power of both lenses o Eyepiece 10X times Objective power (10X, 20X, 40X…) Highest 1000X Highest Maximum magnification is around 1000X LIVE specimens Can be used to study LIVE specimens LIGHT MICROSCOPES

7. *Transmission Electron Microscope (TEM) beam of electrons Uses a beam of electrons to produce an enlarged image of very thinly sliced specimen on screen or photographic plate magnetic lenses Image focused by magnetic lenses 200,000X magnification Cannot be used to view living specimens ELECTRON MICROSCOPES

8. *Scanning Electron Microscope (SEM) 3D 3D image not sliced for viewing Specimens not sliced for viewing Surface sprayed with fine metal coating Surface sprayed with fine metal coating Also uses electron beam and fluorescent screen or photographic plates 100,000X magnification 100,000X magnification Cannot be used to view living specimens Cannot be used to view living specimens ELECTRON MICROSCOPES

10. Body Tube Ocular Lens Revolving Nosepiece Objective lens Stage Clips Diaphragm Light source Arm Stage Course Focus / Adjustment Fine Focus / Adjustment Base

12. The International System of Measurement The International System of Measurement, or SI is the one system of measurements scientists use. ALSO KNOWN AS: The Metric System Tools of the trade

13. The Metric System es Base Units – Uses Base Units Describes what you are measuring. Describes what you are measuring. » Length-meter (m) » Volume-liter (L) » Mass-gram (g) » Temperature-Celsius (C) » Time-second (s) Tools of the trade BASE UNITMEASURES MeterLength LiterVolume GramMass

14. The Metric System Major advantages: Major advantages: – It is a decimal system based on multiples or fractions of 10’s – Commonly used among all scientists – Easy to convert between unit prefixes: – Kilo – 1000 – Deci – 1/10 th – Centi – 1/100 th – Milli – 1/1,000 th – Micro – 1/1,000,000 th …of the base UNIT Tools of the trade

15. In SI, prefixes are added to the base unit to signify the value. Prefixes are multiples of 10… Prefixes are multiples of 10… For example: 1 kilogram = 1000 grams For example: 1 kilogram = 1000 grams 1 centimeter = 1/100 th of a meter 1 centimeter = 1/100 th of a meter 1 milliliter is 1/1000 th of a liter, or 1000 X smaller than a liter 1 milliliter is 1/1000 th of a liter, or 1000 X smaller than a liter TOOLS OF THE TRADE PREFIX…PLUS BASE UNIT Kilo – 1/1000 th Kilo+gram = Kilogram Hecto – 1/100 th Hecto+liter = hectoliter Deka – 1/10 th Deka+gram = dekagram Deci - 10Deci+liter = deciliter Centi - 100Centi+meter = centimeter Milli - 1000Milli+meter = milliliter

16. The SI System makes conversions easier! 1 mile=1760 yards=5280 feet= 63,360 inches – Ugh!! Because all of the unit relationships in the metric system are based on multiples of 10, it is easy to convert between prefix units - just multiply or divide by 10! 100,000 cm = 1000 meters = 1 kilometer 1 kilometer = 1000 meters = 100,000 cm TOOLS OF THE TRADE

17. For example: Centimeters are 10 times larger than millimeters So.. 1 centimeter = 10 millimeters 1101001000.10.01.001 Kilo-Hecto-Deka- BASE UNIT Meter Gram liter Deci-Centi-Milli- Tools of the trade

18. US Conversions within the US Conversions within the Metric System Metric System TOOLS OF THE TRADE

19. Mass vs. Weight (Not the same!) Mass-How much matter (particles) you are made of. Weight-How much gravity pulls on you. A QUICK SIDE NOTE…