Midterm Lab

Question 1

Know the parts of the microscope

Answer 1

ocular lens, objective lens, condenser, course and fine adjustment, rheostat

Question 2

Know the terminology of microscopy

Answer 2

Resolution- shortest distance between two points

Total Magnification- ocular lens x objective lens

Parfocalization- when one lens is in focus, all lens are in focus with adjustment

Question 3

Know what dictates resolution, what can we change to improve resolution, and what wavelength gives us the best resolution.

Answer 3

Dictated by the shortest distance between two points

We can change it by having a shorter wave length

ultraviolet light gives us the best resolution

Question 4

Know conversions in metric, specifically millimeters to micrometers and micrometers to millimeters

Answer 4

1 millimeter = 1000 micrometer

Question 5

Know the different structures that Eukaryotes and Prokaryotes can use for motility and how they differ from each other (how the flagella are different)

Answer 5

Prokaryotic Flagella is fast, eratic, and run and tumble
Eukaryotic is wave like and smooth flagella, Motility; cilia and pseudopods

Question 6

Know what Brownian Motion is

Answer 6

False movement, vibration, H2O molecules knocking them over

Question 7

Know the principles on how basic stain works

Answer 7

Bacteria have a slight negative charge, environment has a slight positive charge

Question 8

Know the process of preparing a bacteria smear

Answer 8

Place a loop of water on slide, transferring another loop of the bacteria, and mixing it in with the water, then heat fix

Question 9

Know the purpose of heat fixing

Answer 9

Binds the bacteria to the slide. Kills the bacteria, allows the bacteria to take up the stain

Question 10

Know each step in the gram stain

Answer 10

Crystal Violet, Iodine, Alcohol, Safranin

Question 11

Know what the result would be if you stopped at each step for each type of gram organism (gram positive and gram negative)

Answer 11

Crystal Violet = purple
Iodine= purple
Alcohol= purple
Safranin= Red

Question 12

Know what the result would be for situations

Answer 12

dead bacteria, too much bacteria on smear will look gram positive, too much alcohol will look gram negative– too long, too little alcohol – too short will look gram positive

Question 13

Know the types of media and what they do

Answer 13

Broth- Growth, Agar Plate- Purity, Agar Slant- Storage, Agar Deep- Motility

Question 14

Know the properties of agar (that make it so useful)

Answer 14

Soldifies @ 40c Liquifies @ 100
non-digestable

Question 15

Fermentation

Answer 15

Breakdown of sugars that are transformed into a new product

Question 16

Know when fermentation occurs (conditions)

Answer 16

Occurs with little to no oxygen

Question 17

Know the purpose of fermentation

Answer 17

NAD

Question 18

Know what CFU stands for

Answer 18

Colony Forming Unit

Question 19

Know what the two common ways to test surfaces in the environment are

Answer 19

Swab or Streak plate

Question 20

Know what the standard plate count tests

Answer 20

Viable organisms