1 - Introduction to Microbiology Flashcards
the scientific study of microorganisms
Microbiology
minute living things that individually are usually
too small to be seen with the unaided eye
Microogranisms
Enumerate some microorganisms
Bacteria
Fungi
Protozoa
Algae
Viruses
aka microbiota
Microbiome
it is microbes that live stably in and on the human body
Microbiome
indefinitely colonize the body
normal microbiota
transiently colonize the body
transient microbiota
Enumerate some parts of a prokaryotic cell
Glycocaly
Cell Appendages
Cell Wall
Plasma Membrane
Cytoplasm
Ribosomes
Inclusion
Nucleoid
Endospores
Enumerate parts of Cell Appendages
Flagella
Axial Filaments
Fimbriae
Pili
aka Sugar Coat
Glycocalyx
a viscous (sticky), gelatinous polymer that is external to the cellwall
Glycocalyx
Composed of polysachharide, polypeptide, or bot
Glycocalyx
made inside the ell and secreted to the cell surface
Glycocalyx
What are the 2 types of Glycocalyx
Capsule
Slime Layer
Contributes to bacterial virulence
Capsule
Protects pathogenic bacteria from phagocytosis
Capsule
Long filamentous appendages that propel bacteria
Flagella
Movement of bacterium toward or away from a particular stiumlus
Taxis
What are some types of taxis
Chemotaxis
Phototaxis
aka endoflagella
Axial Filaments
bundles of fibrils that spiral around the cell
Axial filaments
structure for motility in spirochetes
Axial Filaments
arise and anchored at the ends of the cell beneath an outer sheath
Axial Filament
similar structure to flagella
Axial Filaments
Hairlike Appendages that are shorter, straigter, and thinner than flagella
Fimbriae and Pili
consist of a protein called pilin arranged helically around a central core
Fimbriae and Pili
Present in many g(-) bacteria
Fimbriae and Pili
a few to serveralo hundred per cell
Fimbriae
adhere to surfaces
Fimbriae
longer and fewer than fimbriae (1-2/cell)
Pili
for motility and DNA transfer (e.g. sex pili in conjugation)
Pili
Complex, semi rigid structure
Cell Wall
Enumerate the functions of Cell Wall
- prevents bacterial cell rupture
• maintain shape of bacterium
• point of anchorage for flagella
present in all bacteria, except Mycoplasma and Ureaplasma
cell wall
contributes to the ability to cause disease, the site of action of some antibiotics, differentiates major types of bacteria based on composition
Cell Wall
what is peptidoglycan
aka murein
composed of peptidoglycan (aka
murein) alone or in combination with
other substances
Cell Wall
Repeating Dissacharides
N-acetylglucosamine (NAG) + N-acetylmuramic acid (NAM)
NAG
N-acetylglucosamine
NAM
N-acetylmuramic acid
many layers of peptidoglycan, forming a thick, rigid structure
Gram-Positive Cell Wall
one or very few layers of peptidoglycan and an outer membrane
Gram-Negative Cell Wall
Major permeability barrier for Gram-negative bacteria
Gram-Negative Cell Wall:
Outer Membrane
Lipids and carbohydrates
Lipopolysaccharide (LPS)
released when g(-) bacteria die; causes fever,
shock, blood clotting, dilation of blood vessels)
Lipid A (Endotoxin)
structural function
Core polysachharide
Function as antigen
O Polysaccharide
It is also present in Listeria monocygenes (a Gram-Positive bacteria) but does not function as endotoxin
O-polysaccharide
between inner membrane and outer membrane
Periplasmic Space
present in Mycobacterium and Nocardia
Acid-Fast Cell Wall
contains high concentrations (60%) of a hydrophobic waxy lipid(mycolic acid)
Acid-Fast Cell Wall
Mycobacterium and Nocardia
Acid-Fast Cell Wall
inside the cell wall and encloses the cytoplasm
Plasma Membrane
consists mainly of phospholipids, proteins, glycoproteins, glycolipids
Plasma Membrane
lacks sterols, except Mycoplasma and Ureaplasma
Plasma Membrane
What is the structure of plasma membrane?
Fluid Mosaic Model
What are the functions of plasma membrane
Selective Barrier
Fluid Mosaic Model
Lipid Bilayer
Membrane Proteins
the substance of the cell inside the plasma membrane
Cytoplasm
≈80% H2O and contains primarily proteins (enzymes),
carbohydrates, lipids, ions, and many LMW compounds
Cytoplasm
contains the cytoskeleton, nucleoid, ribosomes, and cytoplasmic inclusions
Cytoplasm
site of protein synthesis
Ribosomes
gives the cell a granular appearance
Ribosomes
consists of protein and rRNA
Ribosomes
What are the 2 subunit of Ribosomes (70s)
Large (50s)
Small (30s)
inorganic phosphate (polyphosphate) that can be
used in the synthesis of ATP
Metchromic granules
Glycogen and starch
Polysachharide granules
lipid
Lipid inclusions
Sulfur and -containing compounds
Sulfur granules
ribulose 1,5-biphosphate carboxylase
Carboxysomes
Hollow cavities
Gas vacuoles
Ferric Oxide
Magnetosomes
no nuclear envelope
Nucleoid
contains a single long, continuous, and circularly double-stranded
DNA called the bacterial chromosome
Nucleoid
bacterial chromosome
no histones
attached to the plasma membrane
also known as extrachromosomal DNA
Plasmid
small usually circular, double-stranded DNA
Plasmid
Replicate independently from chromosome
Plasmid
not crucial for survival but adds some advantages
Plasmid
specialized “resting” cells
Endospores
highly durable dehydrated cells with thick walls and additional layers
Endospores
can survive extreme heat, lack of water, and exposure to many toxic chemicals and radiation
Endospores
resistant to processes that kill vegetative cells (e.g. desiccation, chemicals, radiation, heating)
Endospores
formed internal to the cell membrane
Endospores
contains high amounts of dipicolinic acid (DPA), and calcium ions
Endospores
present in Clostridium and Bacillus
Endospores
spore formation
Sporulation/Sporogenesis
return of endospore to vegetative state
Germination
WHAT ARE THE THREE DOMAINS OF LIFE
Bacteria
Archaea
Eukarya
What are the Five Kingdoms
Fungi
Plants
Animals
Protista
Monera
Enumerate classification of Microorganisms
Prokaryotes
Eukaryotes
Viruses
Prions
unicellular prokaryotes; have peptidoglycan cell
walls; reproduce by binary fission
Bacteria
live in extreme environments and carry
out unusual metabolic processes; no peptidoglycan in cell walls
Archaebacteria
obligate anaerobes that produce CH4 from CO2 and
H2
Methanogens
require high concentrations of salt for survival
Extreme halophiles
require high concentrations of salt for survival
Extreme halophiles
grow in extremely hot environments
Hyperthermophiles
Enumerate classification of Eukaryotes
Fungi
Protists
Animal Parasites
may be unicellular (yeasts) or multicellular (molds
and mushrooms; form hyphae); have chitin cell walls;
reproduce sexually (meiosis) or asexually (spores)
Fungi
eukaryotes that are not plants, fungi, or animals
Protists
unicellular nonphotosynthetic protists; reproduce sexually or asexually
Protozoa
unicellular photosynthetic protists; have cellulose cell walls; reproduce sexually and asexually
Algae
Enumerate classification of Protists
Protozoa
Algae
multicellular eukaryotes
Animal Parasites
Enumerate some Animal Parasites
Flatworms
Roundworms
acellular obligatory intracellular parasites
Viruses
what are some structures of Viruses
Single type of nucleic acid, either DNA or RNA
Protein Coat (sometimes enclosed by an envelope) that surrounds the nucleic acid
multiply inside living cells by using the synthesizing machinery of the cell
Viruses
infectious proteinaceous particle
Prions
Small
Micro
Living things
organism
can be called flora as well, normal flora
microbiota
permanent causing disease
normal microbiota
non-permanent causing disease
Transient microbiota
before nucleus
Prokaryotic
True nucleus
eurkaryotic
What is cell Appendages composed of?
Pili, Fimbriae and Flagella
What is the “S” in the 70s ribosomes
Swedberg unit
What is the 70S in the 70S Ribosomes
Sedimentation rate
extra chromosomal DNA
Plasmid
Glyco
Sugar
is it true that the more virulent is the more disease it causes?
True
It is part of immuneresponse
phagocytosis
what is the main function of flagella?
Locomotion
Flagella surrounds the cell on all surfaces
Peritrichous
has one flagellum
Monotrichous and polar
Has multiple flagella but only in one end
Lophotrichous and polar
Multiple flagella on both ends
Amphitrichous
stimulus is chemical substance
Chemotaxis
stimulus is light
Phototaxis
group of bacteria that helical inshape
Spirochetes
enumerate spirochete bacteruas:
Treponema
Leptospira
Borella
It allows bacteria to move in a corkscrew motion
Axial Filaments
Cell wall le bacteria
Mycoplasma and Ureaplasma
Synthesis inhibitors or inhibit cell wall synthesis is
Beta lactams
some examples of synthesis inhibitors are
penicillins, phylosporines carbapinenes and monobactams
Does teichoic acid exist in Gram-negative cell wall?
No it doesn’t exist
Two types of teichoic acid
Wall teichoic acid
Lipoteichoic acid
is there an outer membrane in a positive-gram bacteria
no, there is none
Which has thicker periplasmic space, Gram-negative cell wall or Gram-Positive cell wall
Gram-Negative Cell Wall has thicker, filled w/ gel like substance.
