4.2 Agar Plates Part 2 Flashcards
What is the function of the differential part of BAP plates?
detect hemolytic activity
What is hemolysis?
breakdown of red blood cells
What are the categories of hemolysis?
alpha
beta
gamma
How do microbes capable of alpha hemolysis appear on a BAP and why?
greenish-brown color colonies due to the incomplete lysis of red blood cells
What is beta hemolysis?
ability of a microbe to completely lyse red blood cells
How do BAPs appear with microbes capable of beta hemolysis?
lysis presents as a distinct zone of clearing around the growing colony
What is gamma hemolysis?
absence or lack of hemolytic activity
What is the appearance of the colonies that are classified as gamma hemolysis?
white/tan in color growing on the red background of the unaffected blood agar plate
What color is a columbia CNA agar?
red
What type of media is a columbia CNA agar?
enriched, selective, and differential media
What does the media of columbia CNA agar contain?
anitmocrobial agents colistin and nalidixic acid
What is the purpose of the columbia CNA agar?
suppress the growth of gram negative bacteria and used to isolate gram positive microbes
What is the columbia CNA agar enriched with?
blood
What is a cholocate agar also known as?
CHOC or chocolate blood agar (CBA)
What type of media is a cholocate agar?
enriched, nonselective, nondifferential media
What is a chocolate agar a derivative of?
blood agar plate
What do chocolate agar plates contain?
red blood cells that have been lysed by heat
What gives the chocolate agar plate its color?
the lysed red blood cells
What is the purpose of the lysed red blood cells in a chocolate agar?
release various growth factors into the media required for the cultivation of fastidious, pathogenic bacteria
What are examples of bacteria you can grow on a chocolate agar?
gram negative Haemophilus influenzae and neisseria meningitis
