Bacteria Flashcards
What are the 4 main attributes of bacteria?
-Prokaryotes
-unicellular
-can be aerobic or anaerobic
-Two Kingdoms:
Archaebacteria and Bacteria
A dye that causes the cell wall of a bacterium to turn a certain color is known as ________ _________.
Gram staining
gram positive is what color?
purple
gram negative is what color?
pink
Why is gram staining useful?
helps you determine what antibiotic to use
Describe the structure of gram positive bacteria
contain peptidoglycans that offer protection an anchorage
Describe peptidoglycans
a layer of sugar polymers with polypeptides woven through them
Gram positive bacteria may release _______.
exotoxins
Describe the structure of gram negative bacteria
contain a layer of lipopolysaccharides on top of a thin layer of peptidoglycans.
Describe lipopolysaccharides
carbs. protruding from a lipid based membrane
What chemical is used to stain gram positive bacteria?
crystal violet
What chemical is used to stain gram negative bacteria?
safranin
When gram negative bacteria die, they release ________.
endotoxins
How do antibiotics work?
break down peptidoglycans so they are affective against gram positive bacteria
Gram negative bacteria are extremely harmful because why?
their LPS layer is toxic which causes fever and shock
How are gram negative bacteria dealt with?
Strong antibiotics and alternative medicines are needed to kill them.
How to bacteria stick to their hosts?
Capsules and/or Fimbriae
Describe capsules
sticky outside layer of polysaccharide or protein used to help the bacteria stick to a host or other colony members.
Describe fimbriae
hair like protrusions used to attach itself to a host
Some bacteria move by using a _______.
flagellum