PRELIM: MICROSCOPE

Question 1

The simplest type of compound
microscope

Answer 1

BRIGHTSFIELD COMPOUND MICROSCOPE

Question 2

refers to the fact that magnified objects appear as dark objects against a bright background.

Answer 2

Brightfield

Question 3

means that a specimen positioned properly on the stage of a microscope and illuminated by a light source will
be magnified by a two-lens system.

Answer 3

Compound

Question 4

THE PATH OF LIGHT
also known as the “light source”.

Answer 4

ILLUMINATOR

Question 5

THE PATH OF LIGHT
Has lenses that direct the light rays through the specimen.

Answer 5

CONDENSER

Question 6

THE PATH OF LIGHT
Light rays then pass into the objective lenses, the lenses closest to the specimen.

Answer 6

OBJECTIVE LENSES

Question 7

THE PATH OF LIGHT
Then the image of the specimen is magnified again by the ocular lens or eyepiece.

Answer 7

OCULAR LENS

Question 8

The oil used in oil immersion is???

Answer 8

CEDAR WOOD OIL

Question 9

OIL IMMERSION OIL REFRACTIVE INDEX

Answer 9

1.516

Question 10

 The use of immersion oil improves the resolving power of the lenses.
 If oil is not used with an oil immersion objective lens, the image becomes fuzzy, with poor resolution.

Answer 10

OIL IMMERSION OIL

Question 11

STRUCTURAL COMPONENTS
Houses the optical parts in the upper part of the microscope.

Answer 11

HEAD/BODY

Question 12

STRUCTURAL COMPONENTS
 Connects to the base and supports the microscope head.
 It also used to carry the microscope.

Answer 12

ARM

Question 13

STRUCTURAL COMPONENTS
Supports the microscope and houses the illuminator.

Answer 13

BASE

Question 14

OPTICAL COMPONENTS
 Remagnifies the image formed by the objective lens;
 standard magnifying power is 10x.

Answer 14

EYEPIECE/OCULAR

Question 15

OPTICAL COMPONENTS
Holds the eyepieces in place above the objective lenses.

Answer 15

EYEPIECE TUBE

Question 16

OPTICAL COMPONENTS
Primary lenses that magnify the specimen.

Answer 16

OBJECTIVE LENSES

Question 17

A rotating turret that houses the objectives.

Answer 17

NOSEPIECE

Question 18

 A bigger wheel used to adjust the LPO in focusing
 used also for initial focusing.

Answer 18

COURSE ADJUSTMENT KNOB

Question 19

 A smaller wheel for final focusing of the specimen using HPO and OIO;
 used also to make the specimen more vivid.

Answer 19

FINE ADJUSTMENT KNOB

Question 20

Where the slide/specimen is placed for focusing.

Answer 20

STAGE

Question 21

It is used to hold the slide in place.

Answer 21

STAGE CLIPS

Question 22

The light source of the microscope.

Answer 22

ILLUMINATOR

Question 23

It is used to collect and focus the light from the illuminator on the specimen.

Answer 23

CONDENSER

Question 24

It controls the amount of light reaching the specimen.

Answer 24

IRIS DIAPHRAGM

Question 25

Moves the condenser up or down to
control the lighting focus on the specimen.

Answer 25

CONDENSER FOCUS KNOB

Question 26

Magnification: 4x (RED)

Answer 26

SCANNER

Question 27

 Magnification: 10x (YELLOW)
 It usually forms the general outline or wider portion of the object.

Answer 27

Low Power Objective (LPO)

Question 28

 Magnification: 40x (BLUE)
 It is longer than the LPO and it forms a bigger image if the object is in focus.
 In most cases, it is used to enlarge specimens that are so small under LPO.

Answer 28

High Power Objective (HPO)

Question 29

 Magnification: 100x (WHITE)
 highest degree of magnification
 It is used to examine stained smear preparations of microorganisms using immersion oil as their medium.

Answer 29

Oil Immersion Objective (OIO)

Question 30

Calculating the Total Magnification

Answer 30

TOTAL MAGNIFICATION = Magnifying power of the eyepiece x Magnifying
power of the objective used

EXAMPLE:
Magnifying power of the eyepiece = 10
Magnifying power of the objective used = 100 (OIO)
Therefore: 10 x 100 = 1000x (The specimen in focus is magnified 1000
times its actual size using oil immersion objective)