Lab Practical

Front 1

Refraction

Back 1

Bending of light as it passes through the objective lens.

Front 2

Objective lens

Back 2

Lens that bends light to produce a magnifide real image.

Front 3

Ocular lens

Back 3

Last lens that magnifies the image one more time.

Front 4

Virtual image

Back 4

Image that appears below or within the microscope.

Front 5

Total magnification

Back 5

Objective lens x ocular lens.

Front 6

Resolution

Back 6

Clarity of an image.

Front 7

Function of immersion oil

Back 7

Prevents the objective from scratching the slide when under high power. Also allows the magnification to be at its highest by keeping the light from bending.

Front 8

Parfocal

Back 8

Lens that stays in focus when magnification changes.

Front 9

Wet mount preparation

Back 9

1. Place a drop of water on a clean slide.
2. Add the specimen to the drop of water.
3. Lower the cover slip

Front 10

Aseptic transfer technique

Back 10

The ability to transfer microbes from one place to another without contaminating the original culture, the new medium, or the environment.

Front 11

To prevent contamination of the sample...

Back 11

Inoculating loop and needles are sterilized by passing through an open flame

Front 12

Aseptic technique using a loop

Back 12

1. Flame the loop
2. Remove the cap
3. Flame the end of the tube 2 or 3 times
4. Obtain sample
5. Flame the end of the tube 2 or 4 times
6. Replace the cap

Front 13

Aseptic technique using a needle

Back 13

1. Flame the needle. (Let needle cool)
2. Obtain sample.

Front 14

Streak plate

Back 14

- Obtaining isolation of individual species from a mixed sample.
- Cell density decreases, leading to individual cells that will be efficiently isolated and grow into colonies.
- Colonies consist of the original cell type only.
- Streak patterns are designed to separate deposited cells (CFUs) on the agar surface so individual cells (CFUs) grow into isolated colonies

Front 15

Streak plate method

Back 15

1. Flame loop
2. Place lid face down on table
3. Streak the culture back and forth in QI
4. Flame loop
5. Streak the culture back and forth in QII
6. Flame loop
7. Streak the culture back and forth in QIII
8. Flame loop
9. Streak the culture into the centre of the plate
10. Flame loop

Front 16

Spread plate

Back 16

Obtaining isolation from a diluted microbial sample that is deposited on an agar plate and spread uniformly across the surface

Front 17

Spread plate method

Back 17

1. Place glass rod in alcohol
2. Using pipette, deposit volume on agar surface
3. Flame glass rod
4. Let rod cool
5. Spread volume on agar surface
6. Place glass rod in alcohol

Front 18

Subculture

Back 18

Transfer microorganism from previous culture to fresh culture. Used to prolong life of microorganism.

Front 19

Undefined media

Back 19

The exact composition and amounts of carbon and nitrogen in there ingredients are unknown. Composed of extracts from plant or animal sources and are rich in nutrients. Useful in growing the greatest variety of culturable microbes.

Front 20

Defined media

Back 20

The amount and identity of every ingredient is known. Useful in growing a narrower range of organisms.

Front 21

Autotrophs

Back 21

Any organism capable of self-nourishment by using inorganic materials as a source of nutrients and using photosynthesis of chemosynthesis as a source of energy. Require the least assistance from their environment. Less fastidious than heterotrophs.

Front 22

Heterotrophs

Back 22

Require preformed organic compounds. More fastidious than heterotrophs.

Front 23

Fastidious

Back 23

An organism that relies heavily on the environment to apply ready-made organic compounds.

Front 24

Nonfastidious

Back 24

An organism that relies heavily on the environment to supply ready-made organic compounds.

Front 25

Colony

Back 25

A visible mass of cells

Front 26

Bacterial colony shape

Back 26

Round, irregular, or punctiform (tiny, pinpoint)

Front 27

Bacterial colony margin

Back 27

Entire (smooth with no irregularities), undulate (wavey), lobate (lobed), filametous (resembles thread), or rhizoid (branched like roots)

Front 28

Bacterial colony elevation

Back 28

Flat, raised, convex, pulvinate (very convex) and umbonate (raised in the center)

Front 29

Bacterial colony texture

Back 29

Moist, mucoid, dry

Front 30

Bacterial colony pigment productoin (color)

Back 30

Opaque, translucent, shiny, dull

Front 31

Pellicle

Back 31

Float on top of broth cultures

Front 32

Sediment

Back 32

Sink to the bottom of the medium

Front 33

Uniform fine turbidity

Back 33

Cloudy throughout the medium

Front 34

Selective media

Back 34

Media designed to enhance the isolation procedure by inhibiting growth of some organisms while encouraging the growth of others

Front 35

Differential media

Back 35

Culture that contains indicators to distinguish between or among different microorganisms based on a difference in colony appearance