Chapter 4 - Bacteria And Archaea Flashcards
How do Bacteria and archaea package DNA?
Bacteria and archaea have nuclear material that is red in the cytoplasm
How do Eukaryotes package DNA?
Eukaryotes have a nucleus
Whose cell wall is made of peptidoglycan?
Bacteria
Whose cell wall is distinct from bacteria and eukaryotes?
Archaea
Who has no membrane-bound organelles?
Bacteria and archaea
What is the cytoplasmic membrane?
A thin sheet of lipid and protein that surrounds the cytoplasm and controls the flow of materials into and out of the cell pool.
Bacterial chromosome (nucleoid)
Composed of condensed DNA molecules.
What directs all genetics and heredity of the cell and codes for all proteins?
DNA
Ribosomes
Tiny particles composed of protein and RNA that are the site of protein synthesis
Cytoplasm
Water based solution filling the entire cell
S layer
Monolayer of protein used for protection and/or attachment
Fimbriae
Fine, hairlike bristles extending from the cell surface that help in adhesion to other cells and surface
Outer Membrane
Extra membrane similar to cytoplasmic membrane but also containing lipopolysaccharide.
What does the outer membrane do?
Controls flow of materials, and portions of it are toxic to mammals when released.
Cell Wall
A semirigid casing that provides structural support and shape for the cell.
Actin Cytoskeleton
Long fibers of proteins that encircle the cell just inside the cytoplasmic membrane.
Actin Cytoskeleton contributes to what?
The shape of the cell
Pilus
An appendage used for drawing another bacterium close in order to transfer DNA to it.
Capsule
A coating or layer of molecules external to the cell wall.
What is the purpose of a capsule?
The capsule serves protective, adhesive, and receptor functions.
What is another name for Capsule?
Slime layer or glycocalyx
Inclusion/Granule
Storied nutrients such as fat, phosphate, or glycogen deposited in dense crystals or particles that can be tapped into when needed.
Bacterial Microcompartments
Protein-coated packets used to localize enzymes and other proteins in the cytoplasm.
Plasmid
Double-stranded DNA circle containing extra genes.
Flagellum
Specialized appendage attached to the cell by a basal body that hold a long, rotating filament.
What is does the rotating filament of flagellum do?
The movement pushes the cell forward and provides motility
Bacterial cells are capable of carrying out what necessary life activities?
Reproduction, metabolism, and nutrient processing
What is it called when bacteria’s act as groups?
Colonies or biofilms.
What is a noncellular, parasitic, protein-coated genetic elements that cause harm to host cells?
Viruses
How many general shapes are there for bacteria?
3
What shape is spheres, oval, bean-shaped, and pointed?
Coccus
What shape is Cylindrical, filamentous, and club shaped?
Bacillus
What bacteria shape is curved?
Vibrio
What is pleomorphism?
Variations in size and shape among cells of a single species.
What are diplococci?
Pairs
What is a tetras?
Groups of four
What is an irregular clusters called?
Staphylococci
What are chains of a few to hundreds of cells?
Streptococci
What is sarcina?
Cubical packet of 8, 16, or more cells.
What is diplobacilli?
pairs of cells with their ends attached.
What is Streptobacilli?
Chains of cells
What are cells of a chain that remain partially attached and fold back, creating a side by side row of cells?
Palisades
How many groups of appendages are there?
Two major groups: flagella and axial filaments/ fimbriae and pili
What do flagella and axial filaments provide?
Motility
What do Fimbriae and pili provide?
Provides attachment points and channels.
What does the basal body do?
Basal body anchors the hook to the cell body.
What is a polar flagellar arrangement?
Flagella attached at one or both ends of the cell.
What is a single flagellum called?
Monotrichous
What are small bunches or tufts of flagellum called?
Lophotrichous
What is amphitrichous?
Flagella at both poles of the cell
What is peritrichous?
Flagella are dispersed randomly over the surface of the cell
What is the movement in response to chemical signals called?
Chemotaxis
What is positive chemotaxis?
Movement of a cell in the direction of a favorable chemical stimulus.
What is a movement of a cell away from a repellant or potentially harmful compound?
Negative chemotaxis
What is the movement toward light?
Phototaxis
What does run mean?
Counterclockwise movement of the flagella, swims in smooth, linear direction towards stimulus.
What is tumble?
Flagellum reverses direction, causes cell to stop and change course, increase number of runs.
What is an axial filament?
Two or more long coiled threads found in spirochetes
What does attachment enhance in some bacteria?
Pathogenicity
Pilus (Plural: pili)
Associated with gram-negative bacteria
What provides adhesion but not locomotion?
Pilus
What is the partial transfer of DNA from one cell to another?
Conjugation
What does fimbriae (plural: fimbriae) do?
Provide adhesion but not locomotion
What are small, bristle-like fibers sprouting off the surface of certain species of bacteria?
Fimbriae
What is fimbriae responsible for?
The formation of biofilms
What do Escherichia Coli and the gonococcus use fimbriae for?
Use fimbriae to adhere to epithelial cells.
Whose composition varies, but most contain protein?
Fimbriae
Pili is also known as what?
Sex pilus
What is the structure of pili?
Long, rigid tubular structure made of pillin protein.
When is pili found?
Only found in gram-negative bacteria.
When is pili used?
Used in conjugation, the partial transfer of DNA from one cell to another
How is the production of pili formed?
Genetically
Endospores are constantly doing what where sterility and cleanliness are important?
Constant intruders
What resists ordinary cleaning methods such as boiling water, soaps, and disinfectants?
Endospores
What is the structure of an S layer?
Thousands of copies of single protein linked together and
When is S layer produced?
Only produced in hostile environments
What is S layer used for?
Used in attachment
Define Glycocalyx
A filamentous network off carbohydrate-rich molecules that coat cells
What does the Slime layer protect the cell from?
Protects cell from loss of water and nutrients and is loosely placed around the cell.
What is more tightly bound to the cell then the S layer?
Capsule
What protects the cell from phagocytosis?
Capsule and it is thicker then the slime layer
What forms capsules?
Capsules are formed by pathogenic bacteria
What do capsules protect bacteria from?
Capsules protect bacteria against phagocytes white blood cells
Plaque protect bacteria on teeth is an example of what?
Biofilms
What infects long-term indwelling of artificial devices?
Biofilms
What is composed of the cell wall, cytoplasmic membrane, and outer membrane?
Cell Envelope
Where is the site of ATP synthesis?
Cytoplasmic membrane
The cell envelope acts as a what kind of unit?
A single protective unit
What is composed of unique lipids?
Bulk of cell walls of Mycobacterium and Nocardia are composed of unique lipids
What is a very-long-chain fatty acid, contributes to pathogenicity, makes them resistant to chemicals and dyes?
Mycolic or cord factor
What is used to diagnose tuberculosis and leprosy?
Acid-fast stain
What naturally lacks a cell wall?
Mycoplasma
What has a membrane that is stabilized by sterols and is resistant to lysis?
Mycoplasma
What is a lipopolysaccharide?
Polysaccharide chain that functions as cell markers and receptors
What is an endotoxin?
It stimulates fever and shock reactions
What anchors the outer membrane to peptidoglycan?
Lipoproteins
What spans the outer membrane, allows relatively small molecules to penetrate, can be altered in size to block harmful chemicals, and defend against certain antibiotics?
Porin Protein
What is embedded with proteins and made of 30 to 40% phospholipids and 60 to 70% proteins?
Lipid Bilayer
What contains a high amount of sterols, stabilizes and reinforces the membrane?
Mycoplasmas
Archaea contains unique branched _____ rather than ____?
Hydrocarbons and fatty acids
What functions as energy reactions, nutrient processing, synthesis, and regular transport of nutrients into the cell and discharge of wast?
Cytoplasmic Membrane
What is selective permeability?
Water and small uncharged molecules diffuse freely
Selective permeability allows for _____ ______ _______ to exist for passage of most molecules.
Special carrier mechanisms
What is more difficult to kill than Gram-positive bacteria?
Outer membrane in Gram-negative bacteria
Infections with _______ bacteria are treated differently than infections with _____.
Gram-positive
Gram-negative
Outer membrane in Gram-negative bacteria make them impervious to ________.
Antimicrobial chemicals
What can interact with human tissues and cause disease?
The cell envelope
What is the cytoplasm?
It’s a gelatinous solution contained by the cytoplasmic membrane
What is the prominent site for the cell’s biochemical and enzymatic activities?
Cytoplasm
What is 70 to 80% water, that contains complex mixtures of sugars, amino acids, and salts, that also contains chromatin, ribosomes, granules, and fibers that act as cytoskeleton?
Cytoplasm
What is made of a single circular strand of DNA?
Bacterial chromosome
What is aggregated a dense area of bacterial chromosome?
Nucleoid
What is DNA tightly coiled around to fit in the cell compartment?
Basic protein molecules
What’re nonessential pieces of DNA, that are duplicated and passed on to offspring during replication?
Plasmids
What has separate, double-stranded circles of DNA, and confer protective traits?
Plasmids
Plasmids is an important agent in what?
Genetic engineering
What do bacterial endospores facilitate?
Facilitate survival
What kind of conditions can endospores withstand?
Hostile conditions
What resists heating, drying, freezing, radiation, and chemicals?
Endospores
What happens when there is a depletion of nutrients, especially carbon and nitrogen sources?
Stimulates endospore formation
What is a sporangium?
A sporulating cell
When does germination begin for endospores?
When favorable conditions arise
The germination agent of endospores stimulates the formation of __________ that break down the cortex.
Hydrolytic enzymes
_______ rehydrates and takes up _______ and ________ grows out of the endospores coat.
Core
Nutrients
Bacterium
What is Bacillus anthracis?
Anthrax
What is Clostridium tetani?
Tetanus (lock jaw)
What is c. Difficile?
Pseudomembranous coli
What is C. Perfringens?
Gas gangrene
What is C. botulinum?
Botulism