Review of Microscopy

Activity 1 Review of Microscopy

Group 3 Castasus, Nathaniel Dela Cruz, Jonabelle Del Rosario, Louise Diosomito, Allen

Prepared slides

Introduction

Microscope

MICROLAB

Philippines

MICROLAB

Philippines

History

Parts &

Functions

MICROLAB

Philippines

Types of

Microscope

Importance

Objectives

& Materials

Procedures

Worksheet

MICROLAB

Philippines

MICROLAB

Philippines

MICROLAB

Philippines

MICROLAB

Philippines

MICROLAB

Philippines

Microscope mikrs "small" and skopen, "to look" or "see" is an instrument used to see objects that are too small for the naked eye.

Microscopy The science of investigating small objects using such instrument. Microscopy is the technical field of using microscopes to view samples and objects that cannot be seen with the unaided eye.

History of the Microscope

Roman's made the objects appear

larger through glasses

Salvino D'Armate made the

first eye glass,

The earliest simple forms

of magnification were

magnifying glasses,

usually about 6x - 10x

Who invented the microscope?

With the advancement of technology and improved

optics, the microscope as we know it today came into

being.

270x

(9x)

Parts & Functions

What makes microscopy a crucial

importance in the field of

microbiology?

Access to the existence of microorganisms

To observe, to manipulate, and to examine diversity of

microorganism through dimensions

Comparison between the different representative microorganisms

in shapes and sizes

- SIMPLE MICROSCOPE - LIGHT COMPOUND MICROSCOPE - ELECTRON MICROSCOPE - SCANNING ELECTRON MICROSCOPE

COMMONLY USED MICROSCOPES

OBJECTIVE S

REVIEW THE CONCEPT OF MICROSCOPY

CALCULATE THE MEASUREMENT OF

MICROORGANISMS

COMPARE THE SIZES AND SHAPES

MICROBIAL DIVERSITY

MATERIALS

COMPOUND MICROSCOPES

MONOCULAR

BINOCULAR

OCULAR MICROMETER

STAGE MICROMETER

PREPARED SLIDES

Aspergillus

Amoeba

Euglena

Bacillus

IMMERSION OIL

LENS PAPER

XYLENE

COTTON

PROCEDURES MAGNIFICATION

Microscope was plugged in

Light was switched

ON

The prepared slide

(Amoeba) was

placed on stage

The specimen area

of the slide was

placed over the

center of the stage

aperture

Coarse knob

adjustment was

raised until image

appears

Image was focused,

iris diaphragm

reduced for best

contrast.

Image was observed

in High Power

Objective. Image

sharpened.

Eyes kept at certain

distance from

eyepiece.

Amoeba proteus

400x

RESOLUTION Bacillus subtilis slide

viewed under Low

Power Objective

Bacteria was focused

under High Power

Objective

Oil Immersion Objective

was shifted in place.

Focused using fine

knob

Small drop of

immersion oil was

applied on the

center of stage

aperture.

Front lens was

immersed in oil and

touched the slide.

Image was focused

using fine adjustment

knob.

After using OIO, the oil

was blotted with lens

paper with xylol.

Measurement of Specimen

A microscope with

ocular micrometer was

used.

The grid lines were

observed in upright

position using LPO.

The stage micrometer

was placed on the

stage and focused on

scale

The first division

coincided with the

division on stage scale.

Number of divisions were

counted on the ocular

micrometer subtended by

number of divisions on

stage micrometer.

Calibration factor for

the ocular unit was

computed.

Answers to Worksheet

Specimen no. 1

Amoeba proteus

Total Linear Magnification: 100x (LPO)

1. Draw the specimen under (a) LPO and (b) HPO

Worksheet

Specimen no.1

Amoeba proteus

Total Linear Magnification: 400x (HPO)

2. How does a microscope magnifies the

image of an object?

3. What characteristic of a glass lens is

responsible for its magnification?

SPECIMEN NO.2

Bacillus subtilis

Total linear magnification: 1000x (OIO without oil)

4. Draw the specimen (a) without Oil Immersion and (b) with Oil Immersion

Specimen no.2

Bacillus subtilis

Total Linear Magnification: 1000x (OIO with oil)

5. Why is it necessary to add immersion oil

on the slide being focused when using

OIO?

Objectives Number of OM division subtended by SM division

Number of SM division subtended by OM division

Value of 1 OM division (in microns)

LPO 20 100 50

6. Compute for the value 0f 1 OM division and fill in Table 1.1.

X(OU) = Y(SU)

6. Compute for the value 0f 1 OM division and fill in Table 1.1.

Objectives Number of OM division subtended by SM division

Number of SM division subtended by OM division

Value of 1 OM division (in microns)

Scanner 8 100 125

LPO 20 100 50

HPO 20 25 12.5

OIO 20 10 5

Total Magnification: 100x (LPO)

Objectives Size of 1 box

Scanner 125 microns

LPO 50 microns

HPO 12.5 microns

OIO 5 microns

1. Find the length and width.

2. What is the diameter?

250 microns and 100 microns

250 microns x 100 microns

Total Magnification: 400x (HPO)


Scanner 125 microns

LPO 50 microns

HPO 12.5 microns

OIO 5 microns





Total Magnification: 1000x (OIO)


Scanner 125 microns

LPO 50 microns

HPO 12.5 microns

OIO 5 microns





7. Calculate for the dimensions of the representative microorganisms using the value of 1 OM and fill in Table 1.2.

Microorganisms Dimension

Amoeba 250 microns x 175 microns

Apergillus (sporangium) 12.5 microns x 12.5 microns

Bacillus 5 microns x 2 microns

Euglena 37.5 microns x 25 microns

8. When calibrating the ocular micrometer for use with the oil immersion

lens, you find that 10 SU coincided 60 OU.

(a) What is the length of each ocular unit?

X = no of boxes occupied by an organism

Y= no of lines occupied by an organism

OU = ocular units

SU = 10 microns (Constant)

X(OU) = Y(SU)

(OU) = Y(SU)/X

(OU) = 10(10)/60

(OU) = 1.67 microns

(b) What is the diameter and length of a microorganisms if its

diameter and length in OU are 2 and 20 respectively? (Show

calculations)

Given:

Length of each box (OU) = 1.67 microns

Diameter = 2 boxes

Length = 20 boxes

Diameter = (1.67 microns) (2 boxes)

= 3.34 microns

Length = (1.67 microns) (20 boxes)

= 33.4 microns

9. Identify the etched numbers in the

objective lenses

LPO HPO OIO

Focal length (mm)

16 mm 4 mm 1.8 2.0 mm

Resolution (microns)

1.1 microns 0.02 microns 6.22 microns

Magnification 10x 40x 100x

Numerical Aperture

0.25 0.55 0.65 1.25 -1.4

Working distance (mm)

4 8 mm 0.5 07 mm 0.1 mm

Conclusion

The microscope is a very powerful tool for understanding the

size, structure and function of different microorganisms that cannot

be seen with the unaided eye and that are not within the resolution

range of the normal eye. It uses different lenses to bend light to

reach the preferred magnification ranging from 40x 1000x

(compound microscope) understanding the capabilities and

limitation of a microscope is important if one is to get the best

results from a microscope.

Documents

Review of Microscopy