Microbiology Review
1. What is Microbiology?
2. 5 kingdom system of classification is based on
____________________________________________________________________________________
3. 3 domain system of classification is based
____________________________________________________________________________________
4. The three domains are:
a. _______________
b. _______________
c. _______________
5. _____________ are acellular entities that must invade a host cell to replicate.
6. _____________ and ____________ are Infectious agents composed only of
ribonucleic acid (RNA).
7. ____________ are agents composed of only protein (cause of mad cow disease).
8. _______________- discovered of disease-causing microbes
9. _______________- direct demonstration of bacteria causing disease (Anthrax).
10. Prokaryotic cells
a. DNA is not enclosed inside a membrane usually contain within one
circular chromosome and in some exceptions two.
i. some may contain a linear one such as Vibrio cholerae ( causes
cholera) and Borrelia burgdorferi (causes Lyme disease)
b. Lack membrane enclosed organelles
c. Divide by ____________________
d. Eubacteria and Archaea are prokaryotic cells
i. Eubacteria or bacteria have a cell wall composed of _____________
ii. Archaea have cell walls composed of ____________________and
have no peptidoglycan
e. Shapes vary between _________ (round), ___________ (rod shaped), and
__________ (spiral)
f. Usually found in a variety of arrangements such as in pairs (diplo-), in
chains (______________),or bunches (______________)
g. ______________- gelatinous, viscous polymer, which can be described as a
capsule in some bacteria when attached firmly to the wall, or slime, if
detached.
h. ______________- long hair-like appendages that are mainly used to propel
bacteria. Rotatory motion.
i. Axial Filaments- like flagella but in bundle. Spiral motion
j. Pili and Fimbriae- small, short hair-like structures may be used to
attach to surfaces.
k. S-Layer- Composed of protein or glycoprotein
i. Protect cell against ion and pH fluctuations, osmotic stress,
enzymes, or other predator bacteria
ii. Helps maintain shape
iii. Contribute to virulence
iv. Helps in adhesion to surfaces
l. ____________________- space often found between the plasma membrane
and outer membrane
m. Bacterial cell wall
i. Gram+ stained bacteria have a monolayer of peptidoglycan
ii. Gram- stained bacteria have a thin or absent layer in its bilayer
wall
iii. Outer layer of lipopolysaccharides can evade phagocytosis
iv. LPS contribute to biofilm formation and attachment to surfaces
n. Cell membrane composed of mainly phospholipids and proteins with
fluidity in a bilayer
i. Bacteria- phospholipids with a polar (hydrophilic) and a nonpolar (hydrophobic) end.
ii. Archaeal membranes- Extreme thermophiles have single layer
membranes with a __________________ structure making it more
rigid than a bilayer membrane.
o. _________________- cytoskeleton with microfilaments, intermediate
filaments and microtubules.
p. _________________ are sites for protein synthesis.
i. Smaller than those in eukaryotic cells and are known as 70S
ribosomes
q. _________________- Small double stranded DNA molecules that exist
independently of the chromosome found in the nucleoid.
i. Read article on Plasmids well
ii. Episomes
iii. Conjugative plasmids
1. F factor genes
2. R factor genes
iv. Col plasmids
v. Virulence plasmids
vi. Metabolic plasmids
11. Eukaryotic cells
a. DNA surrounded by membrane and usually found within various
chromosomes
b. Organelles are enclosed within ____________________
c. Found to make up protists, animals, plants, and fungi
d. Only some protists and plant cells have a cell wall and chloroplasts
e. Fungi have cell walls
f. Cell membrane- phospholipid bilayer with carbohydrates attached to
proteins for cell identification and enzymatic substrates.
g. Cilia and flagella used or movement, anchoring, or communication
h. Cytoplasm compartmentalized
i. Ribosome for protein synthesis with density of 80S.
j. Endoplasmic reticulum
i. _________________endoplasmic reticulum
1. Synthesis of lipids, fatty acids, and storage of calcium
ions
ii. ________________ endoplasmic reticulum
1. Contain ribosomes and protein synthesis occur
k. _____________________- packages and transports nutrients for membrane
repairs (UPS of cells).
i. Vesicles
l. __________________- suicide bags- contain digestive enzymes
m. Vacuoles- not found in animal cells- storage (for water)
n. __________________- power houses- ATP
i. Kreb cycle- oxygen required
o. __________________ (contain chlorophyll- photosynthesis occur- glucose
p. Nucleous- chromatin-chromosomes
i. Nucleolus- ribosome formation
q. Cell wall- cellulose in plants; chitin and cellulose in molds
12. Biofilms- Communities of microorganisms attached to a substrate by a
polymer that can communicate with each other through quorum sensing.
a. Read the article on biofilms well
13. Organisms require energy to survive. However the sources of that energy
vary.
Autotrophs- __________________________________
Heterotrophs- need preformed organic molecules from other organisms (we are
heterotrophs)
Phototrophs- energy source is ______________
Chemotrophs- energy source is the oxidation of organic or inorganic compounds
Lithotrophs- electron source reduced inorganic compounds (from the earth)
__________________- electron source are organic molecules
Organisms require large amounts of nitrogen, phosphorus, and sulfur to reproduce
and grow, besides carbon.
•Growth Factors- Organic compounds that are essential cell components but
cannot be synthesized by the organism.
–These are required to be absorbed from the environment
–Three major classes of growth factors:
•Amino acids used for _______________________
•Purines and pyrimidines important for ________________________
*Vitamins (part of enzyme cofactors)
•Passive diffusion- Glycerol, O2, CO2, and H2O are some of the molecules that will go
through a membrane from an area of high concentration to one of lesser
concentration.
Osmosis is _______________________________________________________________________________
When a cell is hypertonic with respect to its environment water movement will be
from __________________________ to the _____________________.
Isotonic is _______________________________________________________________________________
•Facilitated diffusion- material enters the cell using a __________________________
•Active transport- material, usually ions, move from an area of low concentration
to one of higher concentration with the help of ATP
Culture Media
•There are various types of media such as enriched cultures where a particular
nutrient is added to a sample from nature to obtain and amplify the growth of a
particular strain of organisms.
•Defined or Synthetic Media- One in which __________________________________________
–Can be a broth (liquid) or agar (solidified gel)
•Complex media- media where _________________________________________________
•Agar- most commonly used solidifying agent. It is a sulfated polymer composed
mainly of D-galactose, 3,6-anhydro-L-galactose, and D-glucuronic acid. Usually
extracted from red algae
Functional Types of Media
•_________________ media- contain triptic soy broth and tritic soy agar and are used as a
general purpose media because it can sustain the growth of many organisms.
•Enriched media- specially fortified media to grow fastidious microorganisms such
as those that grow only in the presence of blood agar.
•_________________ media- media that distinguish among different groups of microbes
and even permit tentative identification of microorganisms based on their biological
characteristics
•Selective media- favors the growth of particular microbes.
•Three plating techniques;
__________________- uses inoculating loop to spread cells across an agar surface
__________________- involves diluting a culture and plating the dilutions spread
with special rod
__________________- microorganisms mixed with cool medium before pouring in
plate