Microscope Mounting Specimen.pdf

(1)

Mounting Specimens

Labi

EQUIPMENT AND MATERIALS

YouH rsed

the

_{tollowing items to oompl(te this Ltbsessicn. (The standool kit}

_tot

_{this ho}

ivailable from

wwwthehoit

scientistcon

i

includes the ferns

_{listed in the first group.)}

MATERIALS FROM KIT

• Ovei oS

• Forco

• Fhpi to

• Scalpel

• Shd viil(

* Shdes fiat)

• Stain ethylene Oi re

* Stirriilp rod (optional)

MATERIALS YOU PROVIDE

• i3utiiie liphter (or oilier Paine source)

• Carrot (raw)

• 55j5 Jii(I iiiiIiW1tr

Ms oteiiie(priiciiased1)1 hoiiiernidii)

Petroleum icily

• rpU(iiIiCfl carrot

Specimen: human hair

Specii en: per id water

• Toothpicks

• Vegetahie oil(oliveor similar)

• Watcr, distilled

(2)

BACKGROUND

I ii ist nornt a ‘;poimen hetore t3Li

cart

i;bei

VO

it

with

your

inicioscope

Mountit p oonst

of p

paring the

specimen

(it

tecess ary), placing

it on

microscope slide,

adding

a

drop of w

or another mounting medium,

_{and covering the specimen and medium with a coverslip. lfl thi}

ah session, we’H prepare

and observe

several types ol slide mounts.

PROCEDURE I2-1: MAKING WET MOUNTS

A wet

mount

is

_{the simplest and quickest way to prepare a specimen for observation. Fo mak}

wet mount,

sit

nply

_{position th specimen in the center of a sli Jo, place a}

_{drop of water}

_{or otho}

miii

intant on the specir nen, and lower a

coverslip into place. r

naking

sure to

avoid bubbles.

lti’iit.ipiil.t n”t nilititisti it it is about loin

toi kr’itn ihetin, tdv.uii ntis that It inonni i’. i

loinporary hecaine the moniitingtinOwillovaporate infact,

tonghotquartz-liainpon lininination, watermayovanocite

.ilter only a mini feor two

MOUNTING A HAIR SPECIMEN

I. Obtain a hat ticimerl. (in calmnini’lysnip abtof jOUI

hair, hut rt’ more nierr’stirmgto o.irHHme aopecinenthat

includes theroot,(it’s ilso interesting to compare and

;ontrast the appearanceofspecimens from different

people of diftorent ages and hair cnlnrs, from tile head, lard or mustache, trunk, limbs, pubic. axillary[armpit]

‘pinno. from pets, and no 0111

fomom’ tom tin the 0l)€’cminri ritim mc for ii

nl,rOs,5it‘tile All.tdrop ofw itor, cai’tillly p0511

a coverskp it a45’ angie to the shde, andthen lower ‘‘ovenslipintoplace. Ittheme,ire any hnhhles nnder thr

ovomolip, mine thetip o[ the torcips to torcothem outI

ii icrfit ‘nit shp

‘I Ptmico tho ‘.lidtm urmrttrthe stageclips orii th nechani

‘Page and montgr tile npccmcnuniter the IX ‘iblectivi

A inst the illumination level and diaphragm to obtain Irmaxinnrm contrast, Readiust thero,ifnecessary to oh

maximum Imagedetail Note the amount of detail visit liii main tndy of the bitt versustileboundaries

4 RepeatstepP o view the_{hair mt 1LiOX ann 400X, notir}

lIlyadditional detail tlmat’sv sibie ithigher magnifc..it

Rocordyournbservations ri your lab notebook. Shoot in image ormakea sketch,asshowninFigure P20, to

illustrate the major structUral elements visible in the h

ynu have aneyepiecemebcie, use itto estimate the wid hi hair awl the owe at any structures visible.

Rat,iin this slidei,ir literconnparisorr

* , t’l’: :‘i’’i it ,‘‘ic’i 1 Ii i’ci,’

11;,’ ii’t’.tl.

iIi)l.l’;t.tmti(fi !il ‘i ‘iS its UI offci lmt1p0m’1ii5 inom..tnth

“(on can utoiloot t.t,’UnLiott.t

Son count 15 Iii opuI.•..tr ira‘1:1 Sonis(;iOifco 0 5npf

cbs,01 ,‘iii.titOH 1l’..’...1,’ir Ii

‘iii:. .ii ,‘,‘‘ ‘.‘ i_t.’,ii’/t’•i’

.,.t 1

:

5 r:i’ :rOi .‘‘.,it’/‘‘i1i

1_il t’.’’i’ f ii’,, i.’’l’’.im’’i’t

(3)

[igurcl-2-1:,-ii

—

COMPARING TEMPORARY MOUNTING FLUIDS

[fin rc[r,jctier .ndi fIr’ rrocrrtiiifllid ‘‘DiiLiDeI iiiS

1 major effect errtIrejrric’iiiitaridtypeof ifefiil ‘JisihlO In

a specimen. b’ RIif_{‘rifnrn. a rrol’nmm th;mf} _the_nimni

cOmponent of h,inr ii, ,rfnniit 1 52. elose totfi,if of [lieglris risen in the rnicroscopcr elide ,iretcuver SID.Lot finn from the 133 RI of

water

If a colorless solid oblectiLimmersed inacolorlessliqLnnd

with the canoe refractive index as the object,it disappears.

You can verify this withiiglass stirring rod and some water and vegetable oil. Fill a beaker or other container with water and immerse the stirring rod, The rod remains clearly visible because its RI (about is quite different from the 1 33 RI of water If you replace the water with vegetable oil (RI about 1.5÷) the rod hecorries invisible in thelnqLnnd (or nearly so)

because the refractive indices of the liquid arid solid object are

so similar. It they’re ndentical, the nblect disappears completely

That’s whyit canbe near 1y impossible to see bacteria or other

rnicroorgamnrsms in water unless they are stiiinenf

ii.

errin ‘j’f,ihI’rIi.i’t

ii I’ miii fl’’ ,l.iu rrv.

[IIi’’,f)’ ‘In’Ini’mni’l’i II

‘.“rten Ilu.i’ inn’ liii, tl’c’Iin’Ict’’i \‘‘c’cs,mnnr[ tIe 15 ehprn.fivt mnt’r l’i.ne’’ I neon e,irr’firiy iini

nitthen ,idInm’t tin’ nllnnninn.ntiuin level arncf ifi.ipt

uht,inn the fni,mxiinii a n n;ontr ant Fe’,f(llnnst [[rem, to olifiii nnaxanrmin inimpe detnil Note fbi anne vi’,iblein the memo liridyof the heir versn’ifheb

i ‘livitch to the ,lirl,’ yen nninnbe previoii’ly, mu

noire miii . ru I VteiI veshle ‘mire‘‘nit’ ‘i em., mm;uni’er’c:i’nimn

Cmii ‘mii,’rvnfiu,mmr,,inicirunni Inmennimne icy

Figure I—22: Wet ii’/vnr’nn/) nnonritat brmiirr,rir [renal Ira

Consider the implications of the mounting fluid you the first instance, you used water, by far the most cc

mounting fluid used for wet mounts. In the second ir you used glycerol or vegetable oil, whose RI is close Permountarid ether permanent mounting fluids. Th

arid type of detail differed noticeably between the tv

[fiats why experienced rnicroscoprsts generally kee selection of different nrouritnng fluids readily availab

;‘.,f.’rtiifi.’O’,’r/ urn u’r•rrt erir.ar,:nriei/ .ruu’et.’nrftn’rrrrr1 (rrd.

iouieitrrilroeLnu’, iiirnionjot (I.s).and a f.:iniriiiIiaIcectirr rnon.irrt (t.r.;). Bcetn•.•.rrei rn rbothn.ir inrlivic.boai cull’, are n..msr.naliy rnoi noted uP. eerrearroeurd (err. 2

1_ab —2 Morinnf mm I,[

(4)

PROCEDURE I22: MAKING SMEAR

MOUNTS

Othit frhiilfit

ut What

it

oiiiijd,

iikio run

pie

1

ulitl ur

Itqiitd

piu;irtien

[hit Luntain

hacturia or other ct.II on a hde

nd

then

aner it to

produt;e

a thin layer If

the

ipucimen

toe

it

as-is II to

a

sohd opecimen mix a hit of

it

with a drop of

water or

another mor

[Ii d hefore oin the smear

fOlio ki rtii Di

11..

.isirearirii .orne pee[i!i inoke Si000rO of

glis turing niH hit lit 10110/I fir tico UI thu

0th rt use theeuIrt4,l it secuiiiI1010111 cope huh? or

covislip held it i 1k ungle to the sp:umen stole irud

pr Sill I 1w SiJiicui ii tiitO 0thin 101 .ii iiiut the ce t ;u 1

O/l ll1. .11/shownIii 5th 0Ii 3.

Figure 1-2—3:biilrlii 1 iii,

All h uuI1 you cue t si ‘I roe [h ii lu it

ii tih tilhe .iu it ii; i/I 1Ii i 11ti Ptsluc lifeliv 11051 50111 ii 1. 110111

iii lU 0 iilUioop 0. H

Figure 1—24: Flit tioug i irueor

If Ii

the . Ft. k/eu don [ . -.it ii • sOle0100

ittit ion/re: /00 ouihtrtit theSF010.

ci or or ou rot.

5 Positionthe slidenitthestorge,without tcoverslij

iso theHXobjective to icon for oti ntorestingore omeor. Centerlimit irei in the heldof view.ond no -lOXobjectiveinto position.Recordyourobservuit yourtubnotebook

4 /7

/

(5)

PROCEDURE I’2-3: MAKING HANGING DROP MOUNTS

ie

/

hit tpn

;p

dt

op

roe/hod is

used to observe

living microorg

Otsi irs,

typicolly

protozoi,

ill

tht

iritutil

env ourirent ihe idvuritree to mine the hrngingdrop method is thit you

(OUt

obser

the

or. rims

live otid iindorriged ioIne ibor.it thrir

nuhimo, runVtri

iroririd, tiedirici. jrrd

on,

Hi’ disidvoritoge is

thot

some ot the little buggers ire

tiP.

(You

con

slow them

doWn

by

o iding o drop ot n rethyl cellulose or glycerol to the water.) E3ecius e they con move ;iround in

three

ihn’o I ‘Vms.

t

colt

hi cirollirigino

to

ke’

1 r

thorn

ri

the timId of viow

utd

itt

lor:us

eon (fit pee. orion inbee ion new heri n h n.

elo.lyir’i( o’ii’5 V.it 05. her ire the

t•n.ir.(idotle ‘ [)i5)J( ii’! ne”Oyeii ‘ire

ijflh

fir It, i’1’f1

iiet-edges of the envmrelip 1 fee oemeneoph to termj

hot\ieen iii CoViOip ii1(1tb’elide

I. ‘i h i tti’’”i i]’’liiiI iiL ilti el ti

‘ielp. .tre’iiiin I‘‘nil /

Figtire b25: te(;’,t(rfin ‘‘of‘.;‘“t’ ‘0

.5. Iiv it ii V II 515.1 (well leWiS.O,enter theV .11 iiii tt•

Ce’ WrSSlip .iini lOwer the stile into the Covei’Op. (Ice

5, thin’the lideCiitheStipe. (‘(nitenlic( the dee of 10 oh1

P Aiiiiist fun dieiptimoin to itsiii.iiiet ettllif’ IOUff0,

hilnininilton tothe middle ofitsrange

I f, ii’-. Onlf’io of.notlii itrom,, pfinn.fiehonki beviii

crneoni.e iiin,.mud nepo.nhoin 110 ilide ii i”on’ni,ury t’

tfinettgeftfneitriipin the i’eiileiot the field ofviny,

‘(‘(inn f)I’tOII,it,’ tt’n’IniriiV1,i 011 iOn’ non,, in

or oilier profoi’ninr iifir tot ‘fVIEW ifso icenfen it

het you(urn) inn the tieidofviewand switch to the11

oblectiVe to observe tot ther details. Note thatit

is n

(moves on itsOwn)and Tiny he difficult to keep foci

it ‘nOrrns ‘hound inn the wmter drop.

9. if there alenopr otists visiblein the fieldof view, rec

tile field on the edge of the drop arid rotate the 4X c ole posifiinn.Scanthewater illopto iocate one or deforms, center thearea of interestinthe field of v

androtatethe

lOX

obtective into position to obser V more closely. Continue scanning at tow powerto1w

additional hfetorms, and identity as many different

youcan find

(6)

(7)

rI ii_Itr:

1 Ii r ii hi pi itO nlE i hp

them

₎

To liii (end irde odd one urop 01 rnothviine blue stain, allowit to work for 30 ser orids or so, and tiwn uso

the corner of a tissue or paper towel to draw off the excess stain Add on drop ofwaterto the specimen ar put a coverstip in pIice

REVIEW QUESTIONS

1:

‘\‘ti, I iro iii :id.iriticoo iiiilIrjWhcksut Vv’’d

Iii

rd your ‘l’-’’r v,itriiris i

lb Rep at steps liii Ough 0, using piece of car

to prodi ice a or ipitudinal sectior Compare ar

the stained cr ossection arid longrtndinabsm

and record yniir nhservatron, sonr lab nob?

Q

2:

Why night yn use a monntinp ibid other than water for mskin,e a wet mount”

Q

3:

lAltat_{are tim advantages and di awbacks at, r hanging-dr op mount}

Q

4:

HoWwouldyin slowdown last rrroving livemicroorganismsIn make iteasier to viewthem?

Q

5:

Why might you make both cross-sectional and longitudinal-sectional mounts of a specimen?

Q

6:

If a forestry corrrpan’/ cutsdown_{a tree, which type of section are they performing? if they cut that tree trunk int}

whattype of sectioning are they doing?