Lab quiz 1 intro

Microbiology

Total magnification

Objective lense x Ocular lense= Total magnification

if you increase magnification the field of view _____ in size

Decreases

10 x ____ = 450x

25x

Name the 4 objective lenses

4x Scanning lens

10x Low power lens

40x High dry lens

100x Oil immersion lens

Magnification

To enlarge an image only in appearance, not in Physical size

Name the microscope

1. Ocular lense

2. Body tube

3. Arm

4. Objective lense

5. Stage

6. Condenser

7. Illuminator

8. Coarse Focusing Knob

9. Base

10. Fine focusing knob

11. Light intensity knob

12. Stage knob

13. Nose pice

The microscope has what king of filter?

Blue filter

What inverts an image in the microscope?

The Prism

refractive index

is a measure of the light bending ability of a medium

Resolution

is the ability of the lenses to distinguish two points

What provides greater resolution?

Shorter wavelengths of light

1. Can a microscope with a resolving power of 0.4 nm can distinguish between two points at least 0.4 nm apart

2. Can it distinguish if the points were 0.3 nm apart?

1. Yes

2. No

Aseptic Technique

without contamination

The tip of what is the hottest part of the flame?

inner cone

Inoculate

introduce a microorganism into a new environment

The ocular scale is

UNKNOWN (ocular Units (OU)

The stage micrometer scale is

KNOWN (Millimeters (mm)

How is the calibration done?

by superimposing both scales and determining how many ocular graduations coincide with 1 gradation on the stage micrometer. (line up the 0’s)

The stage Micrometers is in _____ units

micrometer μm

1 mm = how many μm

1,000 μm

how would you convert .5mm into μm

multiply by 1,000, answer is 500μm

Know this about the stage micrometer

Know this about Ocular units

Fing the average calibration

28.4 μm/ou

What is the size of the red blood cell at the 40X objective lens? If the measurments at 40x were 5 μm/ou

100 μm

Culture medium

Nutrients prepared for microbial growth

Culture

Microbes growing in/on culture medium

Broth is

Liquid

Agar is

Solid

Chemically defined media

The exact chemical composition is known

Complex media

It is extracts and digests of yeasts, meat, or plants it has peptones and we don’t know the exact chemical composition

What are proteins composed of?

Amino Acids

Nutrient agar recipe, and what type of media is it?

• Beef extract- source of vitamins and other growth factors

• Peptone- source of amino acids

• Agar

• Deionized water

Its a complex media because we don’t know the exact chemical composition

Agar recipe, and what is its melting and solidification point?

Isolated from red algae.

• Contains polysaccharides.

• Is not a food source for bacteria

• Agar is melted by boiling and solidifies at 42°C.

what temperature was the water bath?

55-65 C

What are the Autoclaving conditions?

– 121ºC, 15 psi, 15 minutes

Sterilized means

no Micro organisms are living

What is a colony?

A colony is a population of cells that come from a single cell or make a group of attached cells

What does CFU stand for?

colony-forming unit

Each colony has how many cells?

Billions