Practical I Flashcards
What are the safety attire required in the lab?
Eyewear, gloves, goggles, aprons, closed-toe and closed-heel shoes, long hair and loose clothing contained.
Eyewear, gloves, goggles, aprons, closed-toe and closed-heel shoes, long hair and loose clothing contained are the requirements of what?
Safety rules for attire in the lab
Disposal rules for the following in the lab:
- Plastic petri plates with bacterial cultures
- Glass tubes with bacterial cultures
- Staining waste
- Broken glass
- Plastic petri plates with bacterial cultures - in biohazard bin
- Glass tubes with bacterial cultures - recycled and autoclaved
- Staining waste - in chemical waste containers
- Broken glass - in sharps container
How do you dispose of plastic petri plates with bacterial cultures in the lab?
In biohazard bin
How do you dispose of glass tubes with bacterial cultures in the lab?
Recycled and autoclaved
How do you dispose of staining waste in the lab?
In chemical waste containers
How do you dispose of broken glass in the lab?
In sharps container
Match the laboratory waste in the first list with the disposal method in the second list.
- Plastic petri plates with bacterial cultures
- Glass tubes with bacterial cultures
- Staining waste
- Broken glass
- Chemical waste containers
- Biohazard bin
- Sharps container
- Autoclaved
- Plastic petri plates with bacterial cultures - biohazard bin
- Glass tubes with bacterial cultures - autoclaved
- Staining waste - chemical waste containers
- Broken glass - sharps container
Why are these characeristics of organisms useful?
They assist in differentiation and identification.
What characteristics of organisms assist in differentiation and identification?
Form, elevation, margin
What is the name and function of #1?
9 is the ocular lenses. They contribute to the total magnification.
What is the name and function of #2
2 is the eyepiece. Connects the ocular lens to the body tube.
What is the name and function of #3?
3 is the body tube. This is the hollow space containing mirrors. Light from the sample travels through the body tube and is reflected through it to the eye pieces.
What is the name and function of #4?
4 is the arm. It connects the body tube to the base and is used to carry the microscope.
What is the name of function of #5?
5 is the rotating nosepiece. It is attached to the other end of the body tube. The nosepiece can rotate to allow the use of four different objective lenses.
What is the function of #6?
6 are the objective lenses. There are four.
- Scanning lens: 4X. Always start with this lens.
- Lower power lens: 10X
- High power lens: 40X
- Oil immersion lens: 100X. Always use oil to prevent scattered light from causing a blurry image.
What is the function of #7?
7 is the mechanical stage. This supports the slide.
What is #8 and what function does it serve?
8 is the condenser. It bends the light to focus on the specimen.
The part below it, #9 is the iris diaphram. Remember, the condenser is above the iris diaphram which serves as the aperature.
What is the name and function of #9?
9 is the iris diaphragm. It acts like an aperature that can be opened or closed to adust the light passing from the leamp to the sample.
It is below the condenser that bends the light to focus on the specimen.
What is the name and function of #10?
10 is the lamp. The lamp provides illumination and is controlled by the rheostat.
What is the name and function of #11?
11 is the base. This is the support of the microscope.
What is the name and function of #12?
12 is the rheostat. It controls the amount of light emitted by the lamp.
What is the name and function of #13?
13 is find focus. It raises and lowers the stage in small increments.
What is the name and function of #14?
14 is the course focus knob. This raises and lowers the stage in bigger increments. Only used with the 4X objective.
Why is it important to recenter the specimen when changing objectives?
The field of vision is smaller with larger objectives and the field of vision will be lost if the specimen isn’t centered.
When focusing with an oil objective, what are the steps?
- Start with 4X objective
- focus
- adjust light
- center
- 10X objective
- refocus
- adjust light
- center
- Change to 40X
- refocus
- adjust light
- center
- add oil to the specimen
- refocus
Name organism and relate to group:
- protists
- algae
- helminths
- fungi
Amoeba; Protist
Name organism and group (kingdom)
Rhizopus; fungi
Name organism and group (kingdom)
Spirogyra; algae and protists
Name organism and group (domain)
Anabeana; bacteria
Name organism and group
Taenia pisiformis; helminths
What domain does each belong to?
- Amoeba
- Anabeana
- Rhizopus
- Spirogyra
- Taenia pisiformis
- Amoeba - Eukaryote
- Anabeana - Bacteria
- Rhizopus - Eukaryote
- Spirogyra - Eukaryote
- Taenia pisiformis - Eukaryote
Calculate size of cell using calibration provided under 40X objective.
1 optical unit (O.U.) x 40X calibration of 2.5 μm = 2.5 μm
(do not consider the 10X ocular lens)
Calculate size of cell using calibration provided under 4X objective.
1 O.U. x 25 μm = 25 μm
Find the size of the cell with 100X objective.
1 O.U. x 1 μm = 1 μm
Find the size of the cell with 10X objective.
1 O.U. x 10 μm = 10 μm
What is broth and how is it inoculated?
Broth is a medium that contains nutrients suspended in a liquid solution; inoculated with a loop.
What is the medium that contains nutrients suspended in a liquid solution and is inoculated with a loop?
Broth
What is agar and how would you inoculate it?
Agar is the solidifying agent in a medium that contains nutrients found in broth; inoculate with a loop or a spreader.
How do you calculate the magnification of a specimen with a microscope?
Ocular lens power X objective lens power
Ocular lens is usually 10X.
- With 4X (scanning lens): 10 X 4
- With 10X (low power lens): 10 X 10
- With 40X (high power lens): 10 X 40
- With 100X (oil immersion): 10 X 100
Identify each tube as broth, agar slant or agar deep.
Broth, agar slant, agar slant, agar deep
What is this called?
Agar plate
How would you inoculate each?
Loop, loop, loop, deep
With what do you inoculate an agar plate?
Loop or streak plate method
How many streaks are on this agar plate?
Three
Why is the streak plate technique used?
To isolate single colonies from single cells. Because of this, a single colony contains only one type of cell.
What is the process by which to complete a streak plate culture?
Know procedure:
- Flame loop
- Dip in original culture
- Spread from sector 1 to 2
- Flame loop
- Spread from 2 to 3
- Flame loop
- Etc.
Only dip into original culture once in beginning.
How many times do you dip the inoculating loop into the culture when completing the streak plate technique?
Once in the beginning.
What is the goal of the streak plate technique?
To obtain single colonies
What are the characteristics of negative stain?
- Negative staining is simple stain
- Won’t reveal anything about cell walls
- Stains background
- Stain is large, uncharged molecules
- Example: India ink