Final exam Flashcards
Define microbiology
The scientific study of microscopic organisms
Define microorganism
prokaryotic or eukaryotic cells
Define pathogen
A microorganism that causes disease in a host organism
hooks contribution
Observed the first microorganism
Pasteur’s contribution
Proposed germ theory
Koch’s contribution
Experimentally demonstrated the germ theory
Fleming’s contribution
Developed the first antibiotic
Explain how Koch’s postulates demonstrated the germ theory.
a. Koch observed that the microorganisms were present in animals suffering from the disease but absent in healthy animals which suggests the microorganism is the cause of disease.
b. He then isolated the microorganism to make sure the microorganism was the cause.
c. He injected this isolated microorganism into a healthy animal and if the animal became sick it would indicate that the microorganism is the cause of disease.
Compare and contrast simple and differential staining techniques used to visualize bacteria.
Simple staining the dye is attracted to the bacterial cell, while in differential staining the bye is repelled from the bacterial cell.
Compare and contrast the structure of prokaryotic and eukaryotic cells.
Prokaryotic cell: Smaller, less complex, lack’s nucleus.
Eukaryotic cell: Larger, more complex, has a nucleus.
Bacilli
single rods or a chain
Coccus
single or double spheres
Tetrad
group of 4
Spiral
vibrio (comma shaped) or squiggly lines
Pili
fibers used to attach to surfaces
Flagella
tails coming from the cell, used to move
Capsule
a layer external to the cell wall, used to protect the immune system
Peptidoglycan
Maintains the structural strength of the cell wall.
Periplasmic space
the space between the inner and outer membrane in Gram-negative bacteria.
Outer membrane
surrounds the cell wall in gram-negative bacteria, protects against harsh conditions.
Teichoic acid
aids in maintaining the structure of the cell wall.
Lipopolysaccharide (LPS)
Found in Gram-negative bacteria, provides structure and a barrier to protect the cell from harsh conditions.
Nucleoid
Contains genes and the genetic information
Plasmid
contain antibiotic resistance genes
Microcompartment
protein-bound inclusions for a specific function, Ex: Carboxysomes, photosynthetic cyanobacteria.
Selective media
favors the growth of certain microbes (1 growth)
Enriched media
a media that only lets certain microorganisms grow.
Differential Media
a media that contains specific chemicals to differentiate species that possess or lack a biochemical process
Endospore
small seed produced in the bacteria that preserves genetic information
Explain and identify the 4 phases of a typical bacterial growth curve.
a. Lag phase: organisms are adapting to a new environment.
b. Log phase: organisms are doubling the population every generation.
c. Stationary Phase: Growth rate is equal with death rate.
d. Death phase: loss the ability to reproduce.