Name the (4) External Features a Prokaryotic Cell Possess?
(3) Structural components for prokaryotic cells?
3. nuclear material
all external features are optional
(3) Structural components for eukaryotic cells
2.larger cell size
Name the cell walls?
What are the components of a peptidoglycan?
1.What is the log part composed of (2)?
2. What are the crossbridges composed of?
3. What are the side chains composed of?
1.Log- composed of two alternating sugars
2.What are the crossbridges composed of?
3.What are the side chains composed of?
What are the (3) components of a gram (-) cell wall?
What is teichoic acid used for?
contributes to the strength of a gram postive cell wall.
What are the (2) components of a LPS?
outter membrane on a gram (-) cell wall
1. O polysaccharide- O antigen used for serotyping
2. Lipid A
Porins- proteins that act as channels.
Function-allow some substances to pass through cell wall.
Why do gram (-) cell walls resist chemicals and antibiotics better than gram (+) cell walls? (2)features
1. LPS-outer lipid membrane
2.Porins- protein channels
These preven chemicals and anitbiotics from penetrating.
(4) steps of a gram stain?
1.crystal violet-primary dye enters both cells. Stain cells purple
2. Iodine applied- mordant and forms larger moleules with crystal violet
3.Acetone OH applied
* Thick peptidoglycan will hold the purple dye and will not wash out. gram + =purple
*Thinner peptidoglycan layer will wash out and release the dye. gram-= colorless
4.Safranin dye= red
Gram- cell will uptake the red dye bc it contains none.
Gram + cell will not uptake the red dye becuase it saturated with purple dye.
The color of a negative gram stain and cell wall type?
The color of a positive gram stain and cell wall type?
Negative gram stain= red thin peptidoglycan, LPS, and porins
Postive gram stain = purple, thick peptidoglycan
What are the (4) characteristics of a Bacteria that lacks a cell wall?
2.Bacteria does not stain- red gram stain
3.Antibiotics will not work
4.Less protection from environmental extremes.
What are the effects of each envoriments on a cell?
Isotonic soln- no effect on cell
Hypertonic soln=Shrink Cell
Hypotonic soln=Burst Cell
What is used for stoping bacterial growth? (2)
These hypertonic solutions perserve food by preventing bacteria from growing by shrinking the cell membrane.
Hypotonic soln effect on a cell with no cell wall?
The cell w/no wall will burst and be destroyed.
A cell w/wall will maintain itself.
Name this piece of internal equipment and function?
Spore-oval swelling at the end of rods
Function- preserve the cell when external conditions threaten cell survival.
(3) Conditions when a bacteria turns into a spore?
3.other threat to cell's survival
What does no cell wall mean about the bacteria?(4)
2.Bacteria cant be gram stained
3.Antibiotics that attack cell walls do not work
4.Bacteria less protection from environmental conditions.
Name two membrane organelles that prokaryotes do not have in their cytoplasm?
What are Bacterial Ribosomes called?
What is their function?
Bacterial Ribosomes are 70s
Eukaryotic Ribosomes are 80s
Why do antibiotics attack bacterial ribosomes and not human ribosomes?
Antibiotics only target 70s Ribosomes bc their different from humans
What is the evidence suggesting that mitochondria and chloroplasts could have once free living?
1. both have 70s ribosomes
2.both have double membrane organellas due to endocytosis
What are membraneous organellas.
What is contained in the cytoplasm of Prokaryotes?
2.Nucleoid- a region that contains circular DNA
3.inclusions-reserve deposits. Lipids, Starch, other compounds
Why are endospores important?
endospores are a defensive strategy against threatening external conditions.