morphology

the shape of an organism’s cells

culture

grow bacteria from samples to observe how grow and gross morphology

diagnostic microbiology

isolate and identify bacteria from a patient sample

normal flora

bacteria that live with us all the time

pure cultures

samples with only one type of bacteria, necessary for accurate study

Petri dish

clear plastic container used to culture bacteria

colonies

the groups bacteria grow in

agar

growth media in the Petri dish

Tryptic soy agar (TSA) is common food used for culturing bacteria. TSA provides the glucose, amino acids, vitamins, and nutrients many bacteria need to live.

isolation streak

the process by which bacteria are streaked onto a plate to form isolated colonies

Tryptic soy agar (TSA)

common food used for culturing bacteria. TSA provides the glucose, amino acids, vitamins, and nutrients many bacteria need to live.

bacteria forms

circular, irregular (pleomorphism), filamentous, rhizoid

bacteria elevation

raised, convex, flat, umbonate, crateriform

bacteria margin

entire, undulate, filiform, curled, lobate

coccus (cocci)

sphere

bacillus (bacilli)

rod

spirillum (spirilla)

spiral

How do bacilli group?

individual cells, chains

How do cocci group?

individual cells, groups of two (diplococci), four (tetrad), eight, or form chains

How do spirilla group?

always individual cells

Gram stain

a test that differentiates bacteria into one of two groups based on their cell wall composition

What is the bacterial cells wall made of?

peptidoglycan (sugars and amino acids)

Gram positive

purple (crystal violet), peptidoglycan thick layer

Gram negative

pink (safranin), thin peptidoglycan layer, more dangerous

lipopolysaccharide (LPS)

layer outside in Gram negative bacteria peptidoglycan (can cause septic shock)

morbidity

having a disease or symptom of disease or the rate of disease in a population

mortality

# of deaths in a certain group of people in a certain period of time