Block 1 - Microorganisms Flashcards
Mitosis is the replication characteristic of what type of cell?
Eukaryotic cells
Prokaryotic cells replicate in what way?
Binary fission (membrane attachment)
Energy production within a eukaryote occurs in what specialized organelle?
the mitochondria
How many chromosomes does a prokaryote possess?
What is the shape?
one; circular
Parasitic worms, protozoa, algae, and fungi are considered eukaryotes or prokaryotes?
Eukaryotes
What microorganism is classified separately and not as an official kingdom of living organisms?
Viruses
What is a significant surface molecule against which antibodies are made and which can be used for identification?
Antigen
Definition: Organisms possessing a major antigen that may be common to more than one species of the genus.
Antigenic Group
Definition: Organisms possessing a specific antigen that is common to only very limited, closely related organisms.
Antigenic Type
What is the term that is defined as a single cell organism without a formed nucleus (no nuclear mebrane) or organelles such as possessed by higher organisms.
Prokaryote (prokaryotic cell)
Cell size in “typical” bacteria is:
Diameter: about _____ to ____ um, some up to __ um
Length: about __ to ___ um; most about __ to __ um
diameter: about .5 to .8 um, some up to 1.5 um
length: about 1 to 6 um; most about 1 to 2 um
Definition: The external (physical) appearance of the cell, colony, or other item.
morphology
When cells are stained Gram-positive, what are the colors?
blue to purple
When cells are stained Gram-negative, what are the colors?
pink to red
What are the general cell shapes of these cells:
- ) Coccus
- ) Bacillus
- ) Coccobacillus
- ) Coryneform or diphteroid
- ) Pleomorphic
- ) Spirochete or spirillum
- ) Coccus - spherical
- ) Bacillus - rod or cylindrical
- ) Coccobacillus - short, plump bacillus which resembles coccus
- ) Coryneform or diphteroid - club shaped or chinese letter shape resembling diphteroid bacillus
- ) Pleomorphic - an organism that common has various distinct forms
- ) Spirochete or spirillum - sprial or corkscrew shape
What is the general shape of coccobacillus?
short, plump bacillus that resembles coccus
With regard to cell arrangement, a single cell has what kind of arrangement?
no particular arrangement
What type of cell arrangement is divided on one plane with daughter cells that remain paired?
pairs
What type of cellular arrangement has division along a singular plane, perpendicular to the long axis of the chain with cells that remain attached “end to end”?
chains
What type of cellular arrangement has division along three planes?
Clusters
What type of cellular arrangement can be described as a “picket fence”; with division on one plane perpendicular to the short axis of the chain?
Palisades
The “palisades” cellular arrangement only occur in what type of cell shape?
Bacilli
Within the structure of bacterial cells, what is the term for the thick, aqueous, and elastic material within the cell wall?
the cytoplasm
What structure within a bacterial cell is composed of cell sap and genetic material and mechanisms?
the cytoplasm
What is the function of the cytoplasm?
metabolism and replication
The cytoplasmic membrane is composed of what percentage of dry weight of the cell?
8-10%
The phospholipid bilayer is composed of _________ “heads” and _________ “tails” that influence movement of aqueous materials through the cellular membrane?
hydrophillic; hydrophobic
What is the term that describes proteins that form channels through which large molecules can pass?
Porins
True or False: Within the cytoplasmic membrane, some proteins can function as enzymes.
True
The cytoplasmic membrane controls transport of most compounds entering and leaving the cell with what type of permeability?
selective permeability
Within a bacterial cell, the cytoplasmic membrane is the site of what production?
energy
Peptidoglycan, teichoic acids, and outer membrane components are synthesized and transported in this cellular structure.
cytoplasmic membrane
Where does the secretion of extracellular hydrolytic enzymes occur?
the cytoplasmic membrane
True or False: The cell wall functions to/as:
A.) provide shape and rigidity
B.) provides protection from the environment and from some antimicrobic agents
C.) site of antibody attachment to major cell antigens
True
Within the structure of a GRAM-POSITIVE cell wall, peptidoglycan makes up what percentage?
60-80%
What molecule strands connect to the cytoplasmic membrane?
teichoic acid
What layer within a GRAM NEGATIVE cell wall creates a periplasmic space between peptidoglycan and the “outer membrane”?
the lipoprotein layer
In a GRAM-NEGATIVE cell, what do the phospholipid bilayer, pore proteins, and lipopolysaccharides make?
the “outer membrane” of the cell wall
What is a lipid with repeating units of various combinations of multiple carbohydrates?
a lipopolysaccharide
Within a GRAM NEGATIVE cell wall, what percentage of peptidoglycan is between what range?
10-20%
Within the bacterial cell, what structure composition has concentrated, dehydrated, and densely packed nucleic acids and metabolic proteins within a thick spore coat?
an endospore
Within a bacterial cell, what structure functions to survive adverse environmental conditions; resisting heat, chemicals, and irradiation?
an endospore
What is the bacterial cell structure that may also be referred to as the glycocalyx or slime layer?
the cell capsule
In a bacterial cell, the capsule is made up from what type of compound?
polysaccharides
What bacterial cell structure has the function(s) described below:
a. ) resistant to phagocytosis
b. ) may “hide” surface antigens
c. ) sometimes assists in attachment (such as dental plaque)
the bacterial cell capsule
What is the term for the long, slender threadlike appendage several times the length of the cell?
flagellum
What is the function of the fimbriae?
To aid in facilitating bacterial attachment to appropriate cells
What type of bacterial cell moves by means of axial filaments that cause a corkscrew motion?
spirochetes
What is the term for the bundles of fibrils arising at ends of cell beneath outer sheath and spiral around the cell?
axial filaments
What is the term for the short, thin, threatdlike glycoprotein strands protruding from the cell?
fimbriae
What is the term for the specialized fimbriae which lengthen and are involved in DNA transfer during conjugation?
sex pili
What is the term for an organism which utilizes non-living organic matter?
saprophyte
What is the term for an organism which lives in or on a host organism from which it secures some advantage such as deriving organic nutrients from a living host?
parasite
What is the term for an organism that have elaborate requirements for specific nutrients which they cannot synthesize?
fastidious
What is the term for the various organic compounds such as hemin, specific amino acids, vitamins, etc. which fastidious organisms are unable to synthesize but with which they must be supplied; often results from the lack of genes for certain metabolic enzymes?
growth factors
What is the term for a growth-supporting substance taken by a cell from its environment and used in metabolic activities?
nutrient
Within oxygen utilization categories, what type of bacteria requires atmospheric oxygen (~21%)?
aerobic bacteria
Within oxygen utilization categories, what bacteria requires reduced oxygen concentration (5-10%)?
microaerophilic
Within oxygen utilization categories, what bacteria requires the absence of oxygen?
anaerobic
Within oxygen utilization categories, what bacteria can grow in the presence or absence of oxygen?
facultative
What is the optimal temperature for medically significant bacteria?
35*C
What is the optimal pH level for medically significant bacteria?
6.8 to 7.4
What is the optimal humidity for medically significant bacteria?
60-80%
What is the optimal CO2 for medically significant bacteria?
Most do not require it but some need 5-7% CO2
What is the term for the material in/on which bacteria grow in the laboratory; contains organic nutrients, water, and possibly other ingredients that help enrich for or select for certain types of bacteria?
culture media
What is the term for a clump of a few million identical bacteria originating from the same bacterium?
colony
What is the typical diameter of a bacteria colony?
1-3mm
What typical/common culture media provides a “solid” surface for bacterial growth?
agar
What are the size of “Atypical” bacteria?
.1 to .3 um
True or False: “Atypical” bacteria are metabolically limited with modified cell structures, if present, and complicated or modified reproductive method.
True
What does laboratory cultivation require with regard to growth of bacteria?
It requires a living host or specially enriched media (agar)
Molds and yeasts are classified as what?
Fungi
What can be described as a single cell organism with an oval or spherical shape that can reproduce by budding new cells from an existing cell or by spore formation with a size of 4 to 15um diameter?
Yeast
In molds, what are described as multicellular, long filamentous cells that branch and intertwine?
hyphae
Molds reproduce by forming _______ on reproductive _________.
spores; hyphae
What term describes a visible mass of myphae (may be cottony, velvety, fluffy or leathery)?
mycelium (pl: mycelia)
What is added to the artificial media to be able to inhibit bacterial growth during longer periods of fungi cultivation in the laboratory?
antibiotics to inhibit bacterial growth
Respectively, how many days does yeast and mold take to colonize?
yeast:
mold:
Yeast: 2 to 5 days
Mold: 5 to 21 days
A virus contains how many types of nucleic acid?
One (RNA or DNA-not both)
What are unaffected by most antibiotics?
viruses
What two structures does an enveloped virus contain that is not present in a non-enveloped virus?
envelope and antigen spikes
What is the term for a complete, fully developed individual virus particle?
virion
The core of a virus are composed of what?
nucleic acid (RNA or DNA-but not both)
A virus capsid is composed of what type of molecule?
protein
What is the term for capsid protein molecules that are aligned closely to the shape of the nucleic acid spiral?
helical
What is the term for the capsid protein molecules that are arranged in groups that form a shape similar to a soccer ball?
icosahedral
The role of proteins of the capsid are to serve as ________ in infection and as a site for attachment.
antigens
The virus envelope, that is not present in some viruses, is composed of a ______ ________ that has ___________ that are the site(s) for attachment and serve as antigens.
lipid bilayer; glycoproteins
The lipid bilayer of the virus envelope provides what from the environment?
general protection
What is the “scientific name” for a bacterial virus?
bacteriophage
What are the terms for the two structures that makeup the head of a bacteriophage?
core and capsid
What are the terms for the three structures that makeup the tail of the bacteriophage?
sheath, tail fibers, and base with enzymatic pins
The core of the bacteriophage is made of _______ while the capsid is made of ___________.
nucleic acid (genetic material); protective protein
What is the column of protein which connects the head to the base and reconfigures into a tube when the virus attaches to a bacterium?
The sheath of the tail
In viruses, where are protein fibers with polysaccharide tips which help in determining the attachment site on bacterial cells?
tail fibers
What structures punch a hole in the bacterial cell wall through which the viral nucleic acid can enter?
base with enzymatic pins
What is released into the cell’s cytoplasm once the capsid is opened during the uncoating of the nucleic acid?
viral nucleic acid
What is the term for this phase?
In this phase viral nucleic acid is transcribed into mRNA (if needed). The viral mRNA is then translated into viral proteins. These proteins inhibit the hosts synthetic mechanisms and normal host activity. The new nucleic acid copies are produced and the new viral capsids are produced.
Eclipse / Synthesis phase
In the maturation phase of virus infection, the new viral nucleic acid copies are packaged into new ____ ________.
viral capsids
What type of viruses bud through the cell membrane In the release phase of virus infection?
Enveloped viruses
Lysis of the host cell is a characteristic of what type of virus?
non-enveloped virus
True or False: In enveloped viruses, the virus retains some of the host cell’s membrane as it buds through it.
True
In non-enveloped viruses, the mature viruses accumulate in large groups awaiting release in what structure of the cell?
cytoplasm
In non-enveloped viruses, what ruptures the cell membrane thus releasing the viruses?
a viral enzyme
During what time can the viral genes replicate as if they were normal host DNA after being incorporated and lying dormant?
In bacteria this is referred to as what?
latency; lysogeny (lysogenic cycle)
What is the isolation and identification time of viral laboratory cultivation?
2 days to 4 weeks; depending on the virus
What type of organism is characterized as free living organisms found in soil and water feeding on algae, yeast, bacteria and other protozoa?
Protozoa!
These medically important phyla are classified by their respective method of locomotion.
Protozoa
Amoebae move by _________, meaning false feet.
pseudopodia
Flagellates move by ________.
flagella
Ciliates move by _________.
cilia
Apicomplexans are also known as _____________ are ___-_______ in their mature form.
sporozoas; non-motile
The general size of protozoa are ____ um to ____ mm.
2 um to 1 mm
Protozoan possess what cell morphology?
They are pleomorphic
How many basic morphological stages do protozoa possess?
2 basic stages
What are the two morphological stages of protozoa? What is the main characteristic of each?
trophozoite: active, vegetative (reproductive), motile, feeding stage and cystic: dormant, nonmotile, nonfeeding stage
Which stage in protozoan morphology is responsible for major pathological conditions within the host?
Trophozoite
What are the two types of reproduction that occur within protozoa?
schizogony and conjugation
What does the word “schizogony” refer to in the reproductive system of protozoa?
Schizogony is the multiple divisions of the nucleus before the cell divides
What does the word “conjugation” refer to in the reproductive system of protozoa?
Two cells fuse; each cell fertilizing the other, then dividing
True or False: Helminths are eukaryotes that are multicellular and generally possess specialized, simple body systems and their locomotion is improved and highly refined.
False; Helminths are eukaryotes that are multicellular and generally possess specialized, simple body systems and their locomotion is reduced or lacking.
Helminthic organisms are classified into phyla according to what two aspects of their body?
morphology (external) and internal structures
What are the two sub-groups of Platyhelminthes (flatworms)?
trematodes (the flukes) and cestodes (the tapeworms)
True or False: Trematodes have a complete alimentary tract that includes the mouth, esophagus, caeca, and anus.
False; the alimentary system of trematodes is partial and includes mouth, esophagus, caeca BUT no anus
In most trematodes, reproduction is considered ___________ which means there are male and female reproductive structures in the same organism (internal fertilization).
monoecious
What organisms have one body portion that is non-segmented and “leaf-shaped”?
trematodes
What organisms have multiple body parts, are segmented with no alimentary tract and also monoecious?
Tapeworms
What three “general” parts make up cestodes?
proglottid(s); scolex and sucker
What are the two types of helminths?
Platyhelminthes (flatworms) ; aschelhelminthes (nematodes (true roundworms))
True or False: Aschelminthes are unsegmented and cylindrical with a incomplete alimentary tract.
False; aschelminthes have a complete alimentary tract
True or False: Platyhelminthes are monoecious while aschelhelminthes are dioecious.
True
What is the term for reproduction in which sexes are separated into male and female worms and fertilization occurs by sexual copulation?
Dioecious
