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Preparing a microscope slide

preparing a slide

preparing a microscope slide correctly

is important if you are to be successful

in your attempt to view cells or other

objects not usually visible to the naked

eye

to practice making a wet mount slide you

can use a small piece of newspaper start

by cutting out one letter we'll use an e

as this is what we want to look at under

the microscope we call this our specimen

place the specimen on top of a

microscope slide using forceps or

tweezers

using the pipette place one drop of

water on top of your specimen it is

important to make sure you only add one

drop of water to the specimen otherwise

the coverslip we are about to add will

float on top of the specimen place one

end of the coverslip on the microscope

slide and using the mounting needle hold

the coverslip

at a 45 degree angle gradually lower the

cover slip on to the specimen quickly

dropping the cover slip on results in

air bubbles getting stuck under the

cover slip you don't want to see these

when you look down the microscope so

remember to lower the cover slip very

slowly now you have completed your wet

mount slide you are ready to stain it a

common stain is methylene blue you do

need to be careful using this as it is

harmful if it is inhaled if it comes

into contact with the skin and if it is

swallowed place the straight edge of a

piece of paper towel or filter paper on

the microscope slide against one edge of

the coverslip squeeze one drop of

methylene blue on to the slide at the

other edge of the cover slip the paper

towel or filter paper will soak up the

water from under your cover slip and as

this happens the methylene blue should

follow the path of the water and the

stain will be drawn under the cover slip

wait until the stain completely covers

the specimen carefully wipe off excess

stain with the paper towel taking care

not to dislodge the cover slip

now your slide is ready to use

after using your specimen slide remove

the coverslip dispose of your specimen

appropriately rinse the slide and the

cover slip and return equipment

an alternative approach is to directly

stain your specimen this time we will

use iodine to stain some onion in order

to view onion cells with the microscope

be careful when using iodine as it is

harmful if it is inhaled if it is

swallowed and if it comes into contact

with the skin iodine is also toxic to

aquatic organisms

ideally eye protection should be worn

your teacher will provide you with a

small slice of onion

using the forceps or tweezers peel off

one layer of membrane from your onion

sample it is important to use very thin

layers when making microscope slides as

if the specimen is too thick the

coverslip will wobble on top of the

specimen place the onion membrane on the

top of your microscope slide and ensure

it is as flat as possible add one drop

of iodine to the specimen remember to

ensure it is only one drop as you do not

want to flood your slide take a

coverslip place one edge on the

microscope slide and using the mounting

needle slowly lower the cover slip over

the specimen your slide is now ready to

view with the microscope

after using your specimen slide remove

the coverslip dispose of your specimen

appropriately rinse the slide and the

cover slip and return equipment

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