LM07: Eukaryotes
This dye is used to observe molds under the microscope.
What is lactophenol cotton blue?
The anaerobic chamber contains these two reagents. Describe the result indicating that oxygen is still present in the chamber.
What is a gas pack and methylene blue oxygen indicator strip? The methylene blue strip will turn blue if oxygen is still present.
The oxidase test is used to identify microorganisms containing this enzyme.
What is cytochrome c oxidase?
The starch hydrolysis test identifies this enzyme.
What is amylase?
The enzyme that breaks H2O2 into water and oxygen.
What is catalase?
Name one disease-causing protozoan from your lab modules.
What is Entamoeba histolytica, Trichomonas vaginalis, Plasmodium falciparum, or Balantidium coli?
How pyrimidine dimers affect DNA replication and transcription.
What is they interfere with accurate copying and reading of DNA? Mutations may occur, potentially leading to cell death.
The key reagents and ph indicator in the MacConkey Agar (MAC).
What is Crystal Violet, bile salts, and neutral red?
What is bright royal blue?
PEA agar inhibits most Gram-negative bacteria by interfering with this essential cellular process.
What is DNA synthesis?
This dimorphic fungus is associated with bird and bat droppings, grows as a mold in the environment, and converts to a yeast form in the lungs after inhalation.
What is Histoplasma capsulatum?
In the Fluid thioglycollate broth (FTB) test this bacteria grows evenly throughout the broth because oxygen does not harm them, but they do not use it.
What is aerotolerant anaerobes?
This multistep process converts nitrate (NO₃⁻) into nitrogen gas (N₂) through intermediates such as nitrite, nitric oxide, and nitrous oxide under oxygen-limiting conditions.
What is denitrification?
The citrate test uses this pH indicator.
What is bromothymol blue?
This type of hemolysis partially breaks down hemoglobin, producing biliverdin. It produces a greenish or brownish discoloration around bacterial growth.
What is alpha hemolysis?
A helminth has a cylindrical body, a pseudocoelom, and separate sexes. Which group does it belong to?
What is Roundworms (nematodes)?
The disadvantage of using a spectrophotometer to measure bacterial growth.
What is it measures both living and dead cells, so it does not give an exact viable cell count.
In the Phenol Red (PR) Fermentation Test, a bright pink color indicates this process has occurred.
What is Peptonization?
This agent is added to the indole test.
What is Kovac’s reagent?
This color indicates a positive indole test.
What is red?
This yeast is commonly associated with pigeon droppings, can cause serious pulmonary infections in immunocompromised individuals, particularly those with HIV/AIDS, and may lead to meningitis.
What is Cryptococcus neoformans?
Describe the advantages and disadvantages of using the Neubauer or Petroff-Hauser chamber.
Advantages: The direct count is much faster than the plate count.
Disadvantages: Both viable and nonviable organisms appear the same under the microscope.
These two genera of Gram-positive bacteria are commonly isolated from mixed clinical specimens using PEA agar.
What are Staphylococcus and Streptococcus?
In the starch test this reagent is added after incubation. Describe a postive result.
What is iodine? If starch was hydrolyzed there will be a clear halo around the bacterial growth in the agar, indicating a positive result.
In the nitrate reduction test, after reagents A and B are added, the broth remains colorless. Zinc is then added, afterwards the broth turns red. What does this indicate?
What is a negative nitrate reduction test? The zinc reduced the remaining nitrate to nitrite, which reacted with the reagents to turn red.