Chapter 3 - Microscopy and Cell Structure Flashcards
What does the term coccus/cocci mean?
A spherical cell shape
What is a rod shaped cell called?
bacillus/bacilli
What is a Vibrio cell shape?
Comma
What is a spirillium shape?
a squiggly shaped cell
What is a spirochete shape?
a corkscrew shape
What is the term for a cell that stays the same shape it’s entire life?
Monomorphic
What does the term Pleomorphic mean?
A cell can change shape over it’s lifetime
What is a 2 long chain of cells called?
Diplo-
What is a 3 or longer chain of cells called?
Strepto-
Which cell shapes can form chains?
Cocci or bacilli
What is a packet of cells of 4 called?
Tetrads
What is a packet of 8 cells called?
Sarcinae
What is a cluster of 9+ cells called?
Staphylo-
Which cell shape(s) can be in packets or clusters?
Cocci
What is the function of the cell wall?
To maintain shape and prevent cell lysis
What are the two main types of bacteria?
Gram-positive and Gram-negative
What is the bacterial cell wall made of?
peptidoglycan (found only in bacteria)
What are the two sugar polymers that make up the peptidoglycan?
NAM (N-acetylmuramic acid) and NAG (N-acetylglucosamine)
What is the string of 4 amino acids called that holds together the glycan chains?
Tetrapeptide chain
What holds the tetrapeptide chains together?
peptide bridges or crosslinks
What two characteristics do Gram-positive cell walls have?
Thick peptidoglycan layers and teichoic acids
What two characters do Gram-negative cell walls have?
Thin peptidoglycan layers and unique outer membranes
Is the outer membrane part of the gram-negative cell wall? yes or no.
Yes
What makes up the outer membrane?
A bilayer of lipopolysaccharides (LPS) that includes Lipid A (immune system recognizes) and O polysaccharide (used to identify species or strains)
Why is the outer membrane important to the medical field?
It signals the immune system of the invasion of Gram-negative bacteria
What do different levels of LPS do to the immune system?
Small levels elicit appropriate immune system responses to eliminate the bacteria and Large amounts lead to a deadly response
What is LPS (lipid A) called?
An Endotoxin
What is an Endotoxin?
A bacterial toxin
True or False? Many antibiotics can easily enter the outer membrane.
False
What are the passageways through the outer membrane called where small molecules can move through?
porins
What is the space between the cytoplasmic membrane and the outer membrane called?
periplasmic space
What color does a Gram-Positive bacterial cell stain?
Purple
What color does a Gram-Negative bacterial cell stain?
Pink
How does penicillin interfere with peptidoglycan synthesis?
It prevents the cross-linking of adjacent glycan chains
What does the enzyme Lysozyme do?
It breaks bonds linking glycan chains.
Found in tears, saliva, and other bodily fluids
