Microscope measurement

You should know already… All parts of the microscope. How to calculate total magnification. How to make a wet mount. What an e looks like in the microscope. Use ONLY the fine adjustment with the… high power objective. It’s darker under high power, so you need to adjust the… diaphragm to let more light in. The field of view is smaller under… High Power

Lesson Objectives: you should be able to: Measure the field of view with a ruler. Estimate the size of a micro-organism. Convert mm to um. Calculate the size of the field of view under HIGH POWER. Practice

How do you measure a Paramecium?

paramecium

paramecium mm

Metric system Review Kilo Hecto Deka Meter Deci Centi Milli Liter Grams 100 1 meter = ______ cm 2 cm = ________ mm 20

Micrometers The small size of cells requires another unit called the micrometer. 1 mm = 1000 micrometers (um)

1mm What if I knew that the diameter of the field of view is 1mm…

K H D _ d c m - - µ 1mm 111 millimeter = ________ 1micrometers1 1mm x 1000 = 1000um K H D _ d c m - - µ

1000 µm What if I knew that the diameter of the field of view is 1000 um… Then the paramecium is… _________um 700

100x

mm 1.5 mm = 1500 um

* * 1500 um

500 um * * 1500 um

How wide is the Amoeba? 2000 mm 1000 um

How wide is the euglena? 4000 mm 2000 um

How many could fit across? 4mm 8

FOV= 4mm. 8 can fit across. 4mm 4000 500 = 8 8

mm 1500 um 25 can fit 1500 um 60 um each 25

Find the diameter of the FOV under Low and High Power 2000 um FOV= __________ FOV= __________

4 times as powerful 2000 um 500 um FOV= __________ FOV= __________

Ex. 1 Microscopic Measurement Total Low Power Magnification= 4 Total High Power Magnification= 800x Low Power Field of View= 1600 um 4 400 um High Power Field of View=

Ex 2. Micro Measurement 4x Magnification LP = 100x Magnification HP = 400x Field of View LP = Field of View HP = ? ? ? ? ? 4x 4mm = 4000 µm 1000 µm

Low Power = 100x High Power = 400x Low Power Diameter = 1600 um High Power Diameter = 400 um If you can see 12 cells under low power, how many can you see under high power? 12 / 4 = 3

Low Power Diameter = 1600 um High Power Diameter = 400 um If 1 cell could fit across the high power diameter, how big is each one? If 2 cells could fit across high power, how big is each one? 400 um 200 um

Low Power Diameter = 1600 um High Power Diameter = 400 um If 4 cells could fit across the low power diameter, how big is each one? If 2 cells could fit across low power, how big is each one? 400 um 800 um

Practice 3 : 8 500 µm 500 µm Low Power FOV = 4000 µm High Power FOV = 1000 µm 500 µm 8 High Power 500 µm

stop

Microscope Measuring Lab #4 Find the Diameter of your Field of View Low power and High power Then Measure: Corn/Zea/Pith Cells Paramecium Stentor White Fish Embryo

Pith Cells/ Corn/ Zea stem Low Power 100x High Power 400x FOV= 2000 um FOV= 500 um

Paramecium, Stentor, Embryo

Review

To locate a specimen on a prepared slide with a compound microscope, a student should begin with the low-power objective rather than the high-power objective because the field of vision is smaller under low power than under high power field of vision is larger under low power than under high power specimen does not need to be stained for observation under low power but must be stained for observation under high power portion of the specimen that can be observed under low power is less than the portion that can be observed under high power

How many micrometers? 2000 um mm 1500 um mm

The protist is about 2.5 mm Or 2500 micrometers 5mm

The protist is about 3 mm or 3000 micrometers 9mm

The protist is about 1 mm or 1000 micrometers 3mm

Micrometers µm If the field of view is 2 mm, how big is the protist? The field of view is 2000 um The protist is 1000 um.

If you look at the same paramecium under a lower power on the microscope, and follow the same steps, what would you find for the size of the paramecium? .5 mm .5 mm 3.0 mm 1.5 mm

Before you begin: Directions Read directions carefully and check them off as you go. Really…read the directions Seriously ..read the directions and do exactly as they say.