Pathology and Microbiology for Mortuary Science CH-21

Pili

Allows cells to transfer genetic material to other cells by the mechanism of conjugation

Binary fission

Also known as simple transverse fission. A method of asexual reproduction in bacteria, in which the cell splits into two parts, each of which develops into a complete individual

Morphology

Bacteria refers to their size, shape and arrangements.

Vibrio

Comma shape

Peritrichous bacterium

Has flagella distributed over its entire cell

Monotrichous bacterium

Has one flagellum

Amphitrichous bacterium

Has one flagellum at either and of its cell

Lophotrichous bacterium

Has two or more flagella on either end of its cell

Flagella

Long, whiplike, filament-containing appendages that propel bacteria

Capsules

Outer coating on prokaryotic cells differs greatly between different species. Only when it is organized and firmly attached externally to the cell wall

Glycocalyx

Prokaryotic cells secrete a sticky, gelatinous coating that surrounds the cell wall

Cytoplasm

Refers to the many functional organelles inside the cell. In contrast, the cytoplasm of prokaryotic cells does not contain functional organelles; instead, it refers to the internal matrix of the material inside the cell membrane

Streptobacilli

Rods arranged in chains

Diplobacilli

Rods arranged in pairs

Three basic shapes of bacteria

Sphere Rod Spiral

Streptococci

Spheres arranged in chains

Staphylococci

Spheres arranged in clusters like grapes

Diplococci

Spheres arranged in pairs

Spirochetes

Spiral bacteria that has axial filaments or endoflagella (the flagellum is inside of the cell).Body rotates like a corkscrew. Includes Treponema pallidum (Syphilis) Borrelia burgdorferi (Lyme disease

Principles of Staining

Staining increases contrast and resolution by coloring specimens with stains/dyes Smear of microorganisms (thin film) made prior to staining Microbiological stains contain chromophore Acidic dyes stain alkaline structures Basic dyes stain acidic structures

Motility

Structures that allow for the movement of cells

Endospore

Thick-walled cell produced by bacterium to enable it to survive unfavorable environmental conditions -Produced by Gram-positive Bacillus and Clostridium -Each vegetative cell transforms into one endospore -Each endospore germinates to form one vegetative cell -Defensive strategy against unfavorable conditions -Concern to food processors, health care professionals, and governments

Bacillus

Those bacteria shaped like a rod

Coccus

Those bacteria shaped like a sphere

Sprilla

Those bacteria shaped like a spiral or helical

Fimbriae

Used for attachment to surfaces