1. Structure and function Flashcards
What are the three morphologies of bacterial cells and what shape are they?
coccus - spherical
rod/bacillus - cylindrical
spirillum - curved or spiral
What are the four cellular arangements?
single
diplo
Strepto
Staphylo
How do some bacteria get their name?
combining arrangement with morphology
In a bacterial cell, how many chromosomes do they have?
one
What shape is DNA in, in a bacterial cell?
circular
What area of the bacterial cell is the DNA and plasmids in?
nucleoid
What type of ribosome do bacteria have?
70S
What type of mitochondria do archaea have?
70S
What is the function of ribosomes?
organelles used for protein production
What is the structure of inclusion bodies?
thin membrane bound granules in cytoplasm
What is the function of inclusion bodies?
storage to reduce osmotic stress in cell
What is volutin, which is a phosphate storage, an example of?
inclusion bodies
What is the structure of gas vesicles?
conical shaped, gas filled vesicles made of protein
What is the function of gas vesicles?
confer buoyancy in planktonic cells
Are water and solutes able to enter gas vesicles?
no
What is the structure of the cytoplasmic membrane?
double layer of fatty acids
Where is the cytoplasmic membrane located?
Around the cytoplasm
What are the three functions of the cytoplasmic membrane?
- separate it from the environment
- selective permeability
- site of energy production
What is the transport of selective permeable membranes facilitated by?
membrane proteins
Where are transport proteins located?
cytoplasmic membrane
What is the structure of glycocalyx and the different arrangement types?
polysaccharides
thick or thin. rigid or flexible
What are the two types of glycocalyxs?
capsules and slime layers
What is the function of the glycocalyx?
attachment, biofilm formation, and added protection from dehyrdations and attackers
What is the arrangement of the capsule clycocalyx?
tight attachment and matrix
What is the arrangement of the slime layer glycocalyx?
loose attachment and matrix
What is the structure of fimbriae and pili?
filamentous protein
Are fimbriae or pili longer and less numerous?
pili
What is the function of fimbriae?
attachment to surfaces and other cells
What is the function of pili?
genetic exchange or attachment/gliding motility
What is the structure of prokaryotic flagella?
a lot of proteins
What is the function of prokaryotic flagella?
locomotion
What is the directed movement of prokaryotic flagella?
spinning like a motor
When prokaryotic flagella move counterclockwise, what is it called?
run
When prokaryotic flagella move clockwise, what is it called?
tumble
What is the flagella of a gram negative bacteria like?
ring like structures through cytoplasm, peptidoglycan and outer membrane
What is the flagella of a gram positive bacteria like?
rings through plasma membrane and thick peptidoglycan
What type of flagella are the flagella of spirochetes?
axial filaments
What is the function of spirochetes’ flagella?
causes bacterium to corkscrew, or rotate
Where is the flagella of spirochetes located?
periplasm
Why does the flagella of spirochetes have to corkscrew?
help the movement through viscous media
What is taxis movement?
directed movement in response to chemical or physical gradients, detected by control sensors
What is brownian movement?
movement due to the environment
What type of motion do eukaryotic flagella make?
wave
What are the two types of bacteria?
gram positive and gram negative
What is a gram stain?
used to easily and quickly tell bacteria groups apart
What color does gram positive turn when stained?
purple
What color does gram negative turn when stained?
pink
What three structures do gram negative and gram positive cells have in common?
plasma membrane
periplasm
peptidoglycan
What is the periplasm of gram bacteria?
space between selectively permeable barriers
Is the periplasm more pronounced in gram positive or gram negative bacteria?
gram negative
What is contained in the perisplasm space?
proteins, essential nutrients, transport apparatus, hydrogen ions
What is the structure of peptidolgycan?
sugar and amino acids in a mesh like structure
What is the function of peptidoglycan?
support cells during osmotic stress
Is the peptidoglycan thicker in gram positive or gram negative cells?
gram positive
What two structures are unique to gram positive cells?
teichoic acids and lipoteichoic acids
What are teichoic acids function?
contribute to negative charge of the cell and cell wall structure
Where are teichoic acids in gram positive cells?
bound to peptidolgycan layer
Where are lipoteichoic acids in gram positive cells?
boudn to membrane lipids
What is the function of lipoteichoic acids in gram positive cells?
regulate cell wall enzymes
What two structures are unique to gram negative cells?
second outer membrane and lipopolysaccharide (LPS)
What is the function of LPS in gram negative cells
barrier against harmful agents, increase negative charge, stabilize the outer membrane
What is the structure of the LPS in a gram negative cell?
core polysaccharide, o-polysaccharide and Lipid A
What does LPS replace most of in the gram negative cell?
lipids in outer membrane
Which bacteria cell contains mycoplasmas?
gram positive