1.4 Microscopy and Measurement Microscopes *Produce enlarged image of object Magnification *Increase an objects size Resolution *To show details clearly

Light Microscope (LM) http://www.biologycorner.com/microquiz/ Specimen must be thin enough to be transparent Know the parts The maximum magnification is about 400X Power of magnification equals ocular lens times objective lens Ocular lens are usually 10X There are 3 objective lenses *low power is 4X *medium power is 10X *high power is 40X http://www.biologycorner.com/microquiz/

Electron Microscopes Used to examine things smaller than cells like viruses Uses a beam of electrons rather than light Much more powerful than LM There are 2 types. Neither are used to view live specimens. http://school.discoveryeducation.com/lessonplans/interact/vemwindow.html

1. Transmission Electron Microscope (TEM) Electrons flow through thinly sliced specimen, good to see internal details Magnifies up to 200,000X

2. Scanning Electron Microscope (SEM) Specimen is not sliced but surface of specimen is sprayed Magnifies up to 100,000X

Measurement Scientists use one single system of measurement SI – International System of Measurements 7 fundamental base units

Measurements Base Quantity Name Abbreviation 1. length meter m 2. mass kilogram kg 3. time second s 4. electric current Ampere A 5. thermodynamic temp. Kelvin K 6. amount of substance mole mol 7. luminous intensity candela cd

prefixes abbreviation factor of base giga G 1 billion mega M 1 million kilo k 1,000 hecto h 100 deka da 10 base base base deci d 1/10 centi c 1/100 milli m 1/1000 micro u millionth nano n billionth pico p trillionth  

Measurements kilo, hecta, deka, base, deci, centi, milli Convert 12.3m into mm, dm, and km