Experiment 3 Cultural Characteristics of Microorganisms

cultural characteristic

differences in the macroscopic appearance of a microorganism's growth; are used as a basis for separating microbes into taxonomic groups; contained in Bergey's Manual of Systematic Bacteriology

abundance of growth

a cultural characteristic in nutrient agar slants; the amount of growth is designated as non, slight, moderate, or large

pigmentation

a cultural characteristic in nutrient agar slants; the coloration of organisms as seen in surface colonies

optical characteristic

a cultural characteristic in nutrient agar slants; evaluated on the basis of the amount of light transmitted through growth; described as opaque, translucent, or transparent

form

a cultural characteristic in nutrient agar slants; the appearance of the single-line streak of growth on the agar surface is designated as:
filiform, echinulate, beaded, effuse, arborescent, rhizoid

filiform

a type of "form" to describe nutrient agar slants; continuous, threadlike growth with smooth edges

echinulate

a type of "form" to describe nutrient agar slants; continuous, threadlike growth with irregular edges

beaded

a type of "form" to describe nutrient agar slants; nonconfluent to semiconfluent colonies

effuse

a type of "form" to describe nutrient agar slants; thin, spreading growth

arborescent

a type of "form" to describe nutrient agar slants; thin, treelike growth

rhizoid

a type of "form" to describe nutrient agar slants; rootlike growth

consistency

a cultural characteristic in nutrient agar slants; can be described as dry, buttery , or mucoid

dry

a type of "consistency" in nutrient agar slants; free from moisture

buttery

a type of "consistency" in nutrient agar slants; moist and shiny

mucoid

a type of "consistency" in nutrient agar slants; slimy and glistening

size

a cultural characteristic in nutrient agar plates; pinpoint, small, moderate, or large

pigmentation

a cultural characteristic in nutrient agar plates; color of colony

form

a cultural characteristic in nutrient agar plates; the shape of the colony as described as follows: circular, irregular, or rhizoid

circular

a type of "form" in nutrient agar plates; unbroken, peripheral edge

irregular

a type of "form" in nutrient agar plates; indented peripheral edge

rhizoid

a type of "form" in nutrient agar plates; rootlike, spreading growth

margin

a cultural characteristic in nutrient agar plates; the appearance of the outer edge of the colony; described as: entire, lobate, undulate, serrate, filamentous

entire

a type of "margin" in nutrient agar plates; sharply defined, even

lobate

a type of "margin" in nutrient agar plates; marked indentations

undulate

a type of "margin" in nutrient agar plates; wavy indentations

serrate

a type of "margin" in nutrient agar plates; toothlike appearance

filamentous

a type of "margin" in nutrient agar plates; threadlike, spreading edge

elevation

a cultural characteristic in nutrient agar plates; the degree to which colony growth is raised on the agar surface is described as follows: flat, raised, convex, umbonate

flat

a type of "elevation" in nutrient agar plates; elevation not discernible

raised

a type of "elevation" in nutrient agar plates; slightly elevated

convex

a type of "elevation" in nutrient agar plates; dome-shaped elevation

umbonate

a type of "elevation" in nutrient agar plates; raised, with elevated convex central region

uniform fine turbidity

a cultural characteristic of nutrient broth cultures (distribution of growth); finely dispersed growth throughout

flocculent

a cultural characteristic of nutrient broth cultures (distribution of growth); flaky aggregates dispersed throughout

pellicle

a cultural characteristic of nutrient broth cultures (distribution of growth); thick, padlike growth on surface

sediment

a cultural characteristic of nutrient broth cultures (distribution of growth); concentration of growth at the bottom of broth culture may be granular, flaky, or flocculent

crateriform

a cultural characteristic of nutrient gelatin (liquefaction); liquefied surface area is saucer-shaped

napiform

a cultural characteristic of nutrient gelatin (liquefaction); bulbous-shaped liquefaction at surface

infudibuliform

a cultural characteristic of nutrient gelatin (liquefaction); funnel-shaped

saccate

a cultural characteristic of nutrient gelatin (liquefaction); elongated, tubular

stratiform

a cultural characteristic of nutrient gelatin (liquefaction); complete liquefaction of the upper half of the medium