Glossary of Tortora Microbiology Chap 4

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Their DNA is not enclosed within a membrand and is one circular chromosome
Their DNA is not associated with Histones, other roteins are associated with the DNA
They lack membrane-enclosed organelles
Their cell walls almost always contain the complex polysaccharide peptidoglycan
They usually divide by binary fission.
What is binary fission?
During this process, the DNA is copied and the cell splits into two cells. Binary fission involves fewer structures and processes than eukaryotic cell division
Their DNA is found in the cell's nucleus, which is seperated from the cytoplasm by a nuclear membrane and the DNA is found in multiple chromosomes
Their DNA is consistently associated with chromosomal proteins called histones and with nonhistones.
They have a number of membrane-enclosed organelles
Their cell walls, when present, are chemically simple.
They usually divide by mitosis
What is Mitosis?
Chromosomes replicate and an identical set is distributed into each of two nuclei. This process is guided by the mitotic spindle, a sootball-shaped assembly of microtubles. Division of the cytoplasm and other organelles follows so that the two cells rpoduced are identical.
What are the two groups of Prokaryotes?
Archaea and Bacteria
Name the typical prokaryotic structures
Cell wall, cell membrane, ribosomes, Nuclear region or Nucleoid
Name the optional features of Prokaryotic cells
Inclusion, Capsule, plasmid, flagella, fimbriae
This structure gives shape and rigidity to cell, provides support and protection and is the basis for GRAM staining
Cell Wall
What is the bacterial cell wall composed of?
Peptidoglycan AKA Murein
A ______ cell does not retain initial stain (pink) and is multilayered and complex
A ______ cell does retain initial stain (purple) and has a thick layer of peptidoglycan
Peptidoglycan is composed of what?
NAG and NAM N-acetylglucosamine and N-acetylmuramic acid
What type of bonding is present in the Peptidoglycan
Beta glycosicdic linkages and can be broken by lysozymes
The Glycan chains are crosslinked by peptide bonds between amino acids attached to muramic acid residues, these links are called?
peptide crosslinks
GRAM- bacteria have a thin layer peptidoglycan cell wall with an ?
Outer Membrane
GRAM+ cell walls contain
Teichoic Acids that end with carboxyl groups
The outer membrane is a lipic bilayer that also contains?
Polysaccharides, Lipid A, Lipo protein and Porins
A channel formed from proteins that allow small molecules to pass the outer membrane is called a ?
Can large molecules pass through the outer membrane?
Between the Outer Membrane and the Plasma Membrane is called the?
Periplasmic space
The periplasmic space contains?
Hydrolytic Enzymes, Binding proteins, chemorecptors
Lipid A is considered?
A endotoxin
The chemical composition of the cell (plasma) membrane consists of?
Phospholid bilayer with hydrophopic protions pointing inward and hydophilic portions remaining exposed to aqueous environment, embedded (integral) proteins, associated molecules, Sterols and hopanoids
The function of the plasma membrane is?
mechanisms of entry and exit creating a selectively permeable barrier
When nonpolar (fat soluble) molecules and gases pass though the plasma membrane doe to their chemical makeup it is called?
simple diffusion
When solutes are transported by transport proteins in membrane it is called?
facilitated diffusion
Facilitated diffusion allows?
Transport of polar molecules
A tube that transports water from one side of the membrane to the other is called a?
The passive transport of water is called?
When a solute concentration in the enviornment equals the solute concentration in the cell it is called
When a solute concentration in the enviornment is less than the solute concentration in the cell it is called
When a solute concentration in the enviornment is greater than the solute concentration in the cell it is called
When cells are in a hypertonic solution and water flows out the cell becomes deydrated this is known as?
Hypertonic environments have potential to ______ bacterial growth.
Slow or stop
When transporter proteins pump molecules across membranes against their concentration gradient
Active transport
How is Active transport driven?
powered by ATP or the "proton motive force"
In bacteria cells there is a process where substances are transported while simultaneously being chemically modified this is called?
Group Translocation
An example of group translocation?
Phosphotransferase system sugars are phosphorylated during transport
The prokaryotic nuclear region is called the?
Two types of DNA found in prokaryotic nucleoids
Genomic DNA and plasmids
Small circular DNA molecules are called?
This may carry genes for such activities as antibiotic resistance, tolerance to toxic metals, the production of toxins, and the synthesis of enzymes
Actively growing cells usually contain _____ copies of the bacterial chromosome?
These are sites of protein synthesis and are composed of rRNA and proteins
What does the Svedbury number tell us?
Size and shape
What are the very long thin appendages attached to the surface of the cell?
These are characteristic of differenct bacterial groups
What are two types of Flagella?
Polar and Peritrichous
Monotrichous, Lophotrichous and Amphitrichous are examples of?
Polar flagellation
How to Flagella move?
ezch flagellum moves by rotation (like a propeller) the energy comes from proton motive forces
Movement of an organism toward or away from a chemical is called?
Bacterial Chemotaxis
What are the two types of Bacterial Chemotaxis?
Postive-movement towards an "attractant" or negative movement away from a "repellent"
Running and tumbling are examples of?
Bacterial Chemotaxis
Fumbriae and Pili are located?
on the Bacterial cell surface
Cell surface structures that are used for sticking rather than movement are called?
Fimbriae=fimbrin protein
A larger cell surface structure that only numbers one or two per cell
Pili are involved in the bacterial?
mating process
A polysaccharide containing material that lies outside the cell is called?
Capsule or Slime layers (glycocalyx)
What are the functions of the capsules
Attachment of pathogens to host, improved resistance to phagocytosis by cells of the immunce system, resistances to drying
poly-B-hydroxyl butyrate (PHB) Glycogen, and ployphosphate are all examples of
Storage Products
What are Bacterial Endospores?
intracellular structures found in some bacteria.
Bacterial Endospores provide resistance to?
Heat, acids, drying, chemicals, radiation, and disinfectants
This is known as a resting structure that does not carry out metabolism but is very impermeable to dyes
Bacterial Endospores
The process of endospore formation within a vegetative cell takes several hours and is known as?
sporulation or sporogenesis
Sporulation is triggered by?
exposure to stressful enviromental conditions
When a endospore converts back into vegetative cells it is called?
Spore Germination
List 4 ways in which prokaryotic cells differ from eukaryotic cells
Has no nuclear membrane or nucleoli, no membrane enclosed organelles, there are no carbohydrates in the plasma membrane and prokaryotic cells have a single circular chromosome that lacks histones
List 4 structures typical of all bacterial species
Cell Wall, Cell membrane or plasma membrane, Ribosomes, and Nuclear region or Nucleoid
List three types of molecules which are typically found in the periplasmic space of GRAM- cells
Peptidoglycan Enzymes Lipoproteins
Toxic portion of the GRAM- cell wall
Lipid A
A region that extends from the cell membrane to the outer membrane of a GRAM- cell
Periplasmic space
Responsible for the negative charge of the GRAM+ cell
Teichoic Acids
Anchors the outer membrane of the GRAM- cell wall to the peptidoclycan layer
Portion of the GRAM - LPS that is consistent in all species
Core Polysaccharide
Two glucose derivatives that are joined together to form glycan chains
Protein channels that allow molecules to cross the outer membrane of the GRAM- cell wall
Antigenic portion of the gram - LPS (varies from species to species)
Outer (O) Polysaccharides
A single flagellum located at one end of a cell
Can act as specific receptors for viral particles
Involved in attachment of bacteria to host tissues
Movement in which the organism swims steadily in a gently curved path
Movement towards an attractant
Positive Chemotaxis
Cause formation of pelicles or scums on the surgace of liquids
Flagella located at both poles of a cell
Reserves of inorganic phosphate
Metachromatic Granules
Motor-like structure that anchors a flagellum into the cell membrane and cell wall
Basal Body
Provides improved resistance to Phagocytosis
Glycocalyx (Capsules & Slime Layers)
Movement away from a repellant
Negative Chemotaxis
Lipid-like substance; storage depot for carbon and energy
Poly-B-Hydroxybutyrate (PHB)
Organism stops and jiggles in place
Chemical always found in spores, but never found in vegetative cells
Dipicolinic Acid
A tuft of flagella at one end of a cell
Involved in bacterial conjugation
Provides resistnace to drying
Glycocalyx (capsules & slime layers)
Starch-like polymer involved in energy storage
Intracellular structrues that provide resistance to heat, radiation, acids, disinfectants, etc.
Flagella in many places around the cell surface
Their DNA is not enclosed within a membrand and is one circular chromosome

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