CH 2 Lecture

Question 1

What book?

Answer 1

Micrographia

Question 1

Who made first book about microscopic observations?

Answer 1

Robert Hooke

Question 2

First person to observe bacteria?

Answer 2

Anton van Leeuwenhoek

Question 3

First man to make a light microscope to view MICROBES?

Answer 3

Anton van Leeuwenhoek

Question 4

What did Anton van Leeuwenhoek used to call microorganisms?

Answer 4

Animalcules

Question 5

Who created the compound microscope?

Answer 5

Galileo Galilei

Question 6

Who perfected the optical objective lens?

Answer 6

Joseph Jackson Lister

Question 7

What year was electron microscope discovered?

Answer 7

1940

Question 8

2 MAIN TYPES of LIGHT MICROSCOPE?

Answer 8

1. Simple (1 lens, short focal length, ~300x)
2. Compound or Complex (2 set of lenses, ~1000x)

Question 9

2 MAIN TYPES of ELECTRON MICROSCOPES

Answer 9

1. Scanning (electron beam moves back and forth)
2. Transmission (electron beam penetrates the cell)

Question 10

4 CHARACTERISTICS OF A GOOD MICROSCOPE

1. Adequate m___ p___
2. High r____ p____
3. Provide good c___
4. Serves your p___

Answer 10

1. magnifying power
2. resolving power
3. contrast
4. purpose

Question 11

OTHER types of LIGHT microscope

1. Used for thick biofilms
2. Use fluorochromes, chemical
3. Used for specimens that cannot be stained
   4 Used for detailed examination of INTERNAL STRUCTURE
   5 visualizes specimens that fluoresce
   6 Detection of immunological reactions
   7 Used to examine living cells
   8 Based on variations of REFRACTIVE INDICES but with diffraction halo
   9 Based on variations of REFRACTIVE INDICES but with NO diffraction halo
   10 Object is dark, bg is light
   11 Bg is dark, object is light
   12 Used for specimens invisible in ordinary light

Answer 11

1. Confocal
2. Fluorescence
3. Dark Field
4. Phase contrast
5. Fluorescence
6. Fluorescence
7. Two-photon
8. Phase contrast
9. DIFFERENTIAL
   INTERFERENCE CONTRAST
   10 Bright Field
   11 Dark Field
10. Dark Field

Question 12

Can the electron microscope be used to observe living organisms?

Answer 12

no

Question 13

TRANSMISSION VS SCANNING ELECTRON MICRSCOPE

Answer 13

transmission
- observer ultrastructure
- viruses

scanning
- only surface features
- 3d

Question 14

ADVANTAGES and DISADVANTAGES of examining living microogranisms

Answer 14

Ad:
- undistorted characteristics
- celullar processes
- motility
simple to prepare

Disad: refractive index similar to water (difficult to observe)

Question 15

2 Techniques to observe LIVING ORGANISMS

Answer 15

1. Wet mount
2. Hanging Drop

Question 16

ADVANTAGES and DISADVANTAGES of stained preparations

Answer 16

Ad:
- provide contrast
- preserved
- killed

Disad
- more complicated to prepare
- more expensive

Question 17

1st step of staining microorganisms (DEFINITION of smear)

Answer 17

SMEAR PREPARATION
- THIN and DRY film of microorganisms left to DRY

Question 18

2nd step of staining microorganisms ( 2 types )

Answer 18

FIXATION - kills cells and makes them sticky to increase apparent diameters

1. Heat (direct flame)
2. Chemical (alcohol) to preserve properties as much as possible

Question 19

3rd step of staining microorganisms

Answer 19

STAINING
-application of biological dyes

DYE - chromophric ions

Question 20

3 TYPES OF STAINS

Answer 20

1. BASIC (positively charged dye) - mostly used
2. ACIDIC (negative)
3. Neutral

Question 21

What staining procedure uses only ONE DYE

Answer 21

SIMPLE STAINING

Question 22

What SIMPLE staining procedure use a dye with the same colour of the cells?

Answer 22

POSITIVE/direct

Question 23

Why is ^^ called positive?

Answer 23

• cells are usually negatively charged kaya didikit sya to enhance the appearance of cells for observation

Question 24

What SIMPLE staining procedure makes the cell colorless or luminous?

Answer 24

Negative/indirect

Question 25

How to perform NEGATIVE SIMPLE STAINING PROCEDURE

Answer 25

parang ung mga nasa tiktok na dugo

Question 26

What staining procedure USES 2 OR more dyes?

Answer 26

DIFFERENTIAL STAINING

Question 27

One of the most commonly used differential staining?

Answer 27

GRAM staining