deck_15199498 Flashcards
consistent means to classify, name (nomenclature), and identify organism.
TAXONOMY
DOMAIN, KINGDOM, PHYLUM, CLASS, ORDER, FAMILY, GENUS and SPECIES
Hierarchical system of classification
Binomial Nomenclature
Carl Linnaeus
generic name and begin with capital letter.
GENUS name
specific name and begin with small letter.
SPECIES name
single-celled organisms (prokaryotes) that belongs to Domain Bacteria.
Bacteria (Bacterium if singular)
is the largest bacteria 0.75mm it shines white because of internal sulfur
THIOMARGARITA NAMIBIENSIS
Bacteria can be classified based on their shaped: coccus/cocci
Spherical
Bacteria can be classified based on their shaped: bacillus/ bacilli
Rod – Shaped
Bacteria can be classified based on their shaped: others
Spiral – shaped
single cells
Coccus
in pairs; spherical, flattened, elongated, or bean-shaped
Diplococci
long chains; immotile and gram-positive; present in family streptococcaceae
Streptococci
four cells; divide into 2 planes
Tetrad
eight cells; divide in perpendicular plane; strict anaerobe
Sarcina
single cells; endospores; anaerobes
BACILLUS
grape-like clusters; cell divides in both the planes; immotile and gram-positive
Staphylococci
resemble both as cocci and bacilli; shorter and stumpy
Coccabacilli
comma
Vibrio
– in pairs; after cell division, the 2 cells do not divide and grow in attached arrangement
Diplobacilli
– chains; cell divides in single chain
Streptobacilli
spiral bacteria having helical shape; flexible
Spirochetes
picket structure
Pallisades
thick; purple; pentapeptide; tetrapeptide
b. Gram-positive bacteria
same with spirochetes but more rigid; lack endoflagella
Spirilla
thin peptidoglycan cell walls; light red or pink; direct link
a. Gram-negative bacteria
bacteria can’t be stained; species of mycoplasma, chlamydia and rickettsia
c. Atypical
GRAM STAINING was developed by
HANS CHRISTIAN GRAM
categorizes bacteria acc. to their Gram character; allows determination of cell morphology, size and arrangement
Gram staining
outer layer enclosing the cytoplasm:
- Cell envelope
prevent the cell from expanding & bursting due to water uptake; encloses the protoplasm
a. Cell wall
present immediately beneath the cell wall/ inner surface of cell wall and separating it from cytoplasm
b. Cytoplasmic or plasma membrane –
sugar coat; thick outer covering of the plasma membrane
- Glycocalyx
consist of polysaccharide molecules with the cell wall; thicker than slime layer; acts as virulence to evade phagocytosis.
a. Capsule
– glycoproteins molecules; thin glycocalyx layer; aids in the adherence; protects the cell from dehydration and nutrient loss
b. Slime layer
flagella, pili, fimbriae
- Filamentous appendages
for motility present in swimming and swarming bacteria; long hair like helical filaments;
a. Flagella
longer, thicker and fewer in number than fimbriae; long conjugation or sex pili – aid in bacterial conjugation – transfers genetic material to another contact
b. Pili
threads or fibers; tiny bristle – shorter and thinner than long conjugation pili; attaches the bacterium to surface
c. Fimbriae
containing variety of organic and inorganic solutes containing 80% h2o and 20% salts and proteins; rich in ribosomes, DNA & fluid; site for cell’s biochemical and synthetic activities
- Cytoplasm
protein synthesis; smaller than the ribosomes of eukaryotic cell
- Ribosomes
vesicular tubules formed by invagination of plasma membrane into cytoplasm; principal sites of respiratory enzyme
- Mesosome
most bacteria have single large circular chromosome, but this is not universal. Many species have multiple chromosomes, other species have linear chromosomes.it is located in a nucleoid and many bacteria contain extra-chromosomal elements such as plasmids.
- Bacterial Chromosome
has ability to absorb excess of nutrients in the environment and they are the storage reserve for granule, phosphates and other substances. Can take the form of granules, crystals or globules, some are amorphous.
- Cytoplasmic inclusions
spores” (simplified forms of bacteria) consisting of the DNA genome. Virtually immortal and can be re-activated after lying dormant for hundreds or perhaps millions of years. It can be nearly impossible to prevent infections caused by pathogenic species of class bacilli and class clostridia.
BACTERIAL ENDOSPORE
from the active vegetative cell to release and germination.
Sporulation cycle
unicellular organisms. It is extremophiles.
DOMAIN ARCHAEA
is an organism that thrives in extreme conditions.
Extremophile
composed of ether linkages with branched isoprene chains
a. Archaeal cell membrane
- lack peptidoglycan, some contain pseudopeptidoglycan or pseudomurein.
b. Archaeal cell walls
Living functions of the archaeon is in the _______ and where the DNA is located and exists as a single loop called a plasmid
cytoplasm
how many flagella does it have?
1 or more
used for attachment to surfaces
- Pili
unique archaean structure; discovered in marine archaeal strain; hollow tube like structures; means of anchoring a community of cells to a surface
- Cannulae
unique to archaea; long helical tube with 3 hooks; allow cells to attach both to one another and to surface.
- Hami or (hamus) if singular structure
