Bacterial cell structure Flashcards
Name the bacteria:
Cocci
Name the bacteria:
Bacilli
Name the bacteria:
Coccobacillus
Name the bacteria:
Vibrios
Name the bacteria:
Spirilla
Name the bacteria:
Spirochaetes
What is the binary fission sequence in bacteria?
1) Chromosome replication begins
2) Replication continues
3) Replication finishes
4) Two daughter cells result
What is it called when there is only one plane of cell division?
Diplococci/streptococci
What is the structure called when there are two planes of cell division?
Tetrade
What is the structure called when there are three planes of cell division?
Sarcinae
What is the structure called when there are multiple planes of cell division?
Staphylococci
If there is no sticking between bacterial cells what is this called?
Monococci
What is the glycocalyces?
“Sugar cup” -surrounds the bacterial cell can be in a capsule form or slime layer
What is the long thin filament that extends outward from the cell?
Flagella
How does the flagellated bacteria move?
A biased random walk
Name the structure:
-Rod-like extensions
-Rigid
-numerous
-smaller than flagella
-act as “grappling hooks”
Fimbriae
Name the structure:
-Specialized fimbriae
-How bacteria have sex
-How conjugation happens: sharing genetic information and immunities with other bacteria
Pili
Name the structure:
-Found on virtually all Bacteria
-Roles include:
protection, attachment to other bacteria, resistance to osmotic forces, give shape to the cell
Bacterial Cell wall
A polysaccharide comprised of repeating N-acetylglucosamine(NAG) and N-acetylmuramic acid (NAM)
Peptidoglycan
Is this picture gram-positive or gram-negative?
Gram-negative
What is found in the gram-negative cell wall?
Lipopolysaccharide (can be very toxic)
The most common staining technique in biology; differentiates between gram negative and gram positive:
The gram stain
A gram-positive cell wall means that the cell wall is thick, there is only one layer, and there is no outer membrane.
Gram-positive
What is used during the gram stain that causes the crystal violet color from the first step to stick to the cell?
Mordant (iodine)
During the third step of gram staining what is added and why?
ethanol and acetol - to decolorize the stain
Gram-negative stain will be colorless and gram-positive will stay purple.
What are you adding during the fourth step of gram staining and what is it’s purpose?
Counter stain; safranin
adds a pink color to cell walls
gram-positive will remain purple and gram-negative will become pink from safranin stain
Why does the gram stain fail to identify mycobacterium and nocardia bacteria?
They have very waxy cell walls that reject the crystal violet stain. (these are gram-positive)
Instead, the acid-fast staining technique is used.
What colors are the bacteria when using acid-fast staining?
Acid-fast bacteria-pink/red
non-acid-fast: blue
What does the bacterial cytosol consist of?
ions, carbs, proteins, lipids, waste products
Does bacteria contain a nucleoid region?
Yes
What do inclusions consist of?
They are deposits of: lipids, or starch, or phosphorous, or nitrogen, or sulfur-containing compounds.
surrounded by a protein membrane
What two bacteria can create endospores?
Bacillus and Clostridium
What is the purpose of the endospore form?
It’s a type of “hibernating” resistant form which allows the bacteria to survive in unfavorable conditions.
resistant to drying, heat, radiation, lethal chemicals
