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BIO 205 Exam 1: Topics 1 (1-40), 2 (41-80 ) , and 3 (81-120)

Terms in this set (120)

The nucleus
is a double membrane sac containing DNA and is found in eukaryotes.
The order of reagents in the Gram stain reaction are
crystal violet, iodine, alcohol, safranin
Newly emerging or reemerging diseases
may be due to changing lifestyles, are exemplified by Lyme disease and toxic shock syndrome, AND may reflect a breakdown in sanitation/social order.
Phagocytosis
is the ingestion of particles and may be performed by animal cells.
Immunoflourescence
uses fluorescently tagged molecules, makes use of the specificity in binding of anitbodies, AND would require a special UV microscope.
In a basic staining procedure, which is the correct order?
Smear, fix, stain
The endospore stain
is applicable to only a few groups of bacteria AND usually shows the spores as green structures among a background of pink cells
In viewing a microscopic specimen, oil is used to
decrease the refraction AND increase the resolution.
Movement in bacteria
is often referred to as run and tumble AND may involve pili
Which is not usually true of archaea?
-they are found as rods, spheres, or spirals
-they reproduce by binary fission
-they contain rigid cell walls
-they are found as single cells
X-They contain peptidoglycan as part of their cell walls<--this is only in bacteria
the proteins of bacteria that are involved in the movement of small molecules into the cell are called
transport proteins, permeases, AND carriers.
The cell types that lack a membrane-bound nucleus are found in the
prokaryotes AND archaea
The structures still present in the hay infusions used in experiments on Spontaneous Generation that made them difficult to sterilize are
endospores
Plants are dependent on microorganisms for
changing atmospheric nitrogen to a usable form
Smallpox
has been eliminated as a naturally occurring infection in human beings, AND was dealt with by vaccination
The microscope that allows the specimen to appear three-dimensional is the
interference microscope
The idea of Spontaneous Generation postulated that
living organisms could spontaneously arise from non-living material
Prions
are only composed of protein
The Golden Age of Medical Microbiology
occurred during the late 1800s to early 1900s, is a time when the knowledge of and techniques to work with bacteria blossomed, AND was when people realized that diseases could be caused by invisible agents.
The acid-fast stain
is useful for distinguishing a small group of organisms, including Mycobacterium AND uses carbolfuchsin and methylene blue
Basic dyes
have positive charges
Your instructor wants you to bring in an example of a biofilm to your lab. Which choice is the best selection for bringing in an intact biofilm for further study?
Disconnecting and bringing in the old, mildewed showerhead from the showers in your dorm.
Individual atoms on the surface of prepared samples can be observed using the
atomic force microscope
The cell wall of Gram-negative organisms
has a thin peptidoglycan layer AND is characterized by an outer membrane containing LPS
The cytoskeleton
is a dynamic structure composed of microtubules, microfilaments, and intermediate filaments.
The Gram stain and the endospore stain both use
safranin
The two magnifying lenses found in a light microscope are the
ocular and objective lenses
The macromolecule found in the cell walls of all bacteria is
peptidoglycan
The resolving power of a microscope is described as the ability of the microscope to
separate clearly two objects that are very close together.
Which is not true of mitochondria and chloroplasts?
-They generate ATP
X-They are found in all organisms
-They contain DNA and 70S ribosomes
-They are capable of performing protein synthesis.
Which molecules are associated with the cell wall of Gram-positive bacteria?
peptidoglycan, D-form amino acids, AND teichoic acids
Bioremediation refers to
using bacteria to clean up pollutants
A microbiologist obtained two pure isolated biological samples: one of a virus, and one of a viroid. What type of molecule can differentiate between the two?
Protein
Extrachromosomal DNA is found in...
mitochondria AND plasmids
Which amino acid is found only in the cell walls of bacteria?
Diaminopimelic accid
Which term(s) refer to bacterial morphology?
Coccus AND bacillus
Electron microscopes differ from light microscopes in that
-electrons replace light
-electromegnets replace glass lenses
-resolution is higher
-magnification is higher
X-All choices are correct
Viruses
are obligate intracellular parasites
The word "Animalcule" was coined by
Van Leeuwenhoek
The structures used for motility in both eukaryotes and prokaryotes are
flagella
Oxygen serves as the terminal electron receptor in
aerobic respiration
NAD in its reduced form is abbreviated as
NADH
Organisms that use organic molecules as their source of carbon are called
heterotrophs
What happens to the carbon molecules in the pyruvic acid that goes through the TCA cycle?
They become carbon dioxide
Which is true of competitive inhibition?
A substrate and inhibitor both bid to the active site AND a sulfa antibiotic is a competitive inhibitor
A solidifying agent used most successfully in bacterial nutrient media is
Agar
All the bacterial cells that result from the replication of a single original bacterial organism are said to be a
pure culture
The enzymes that deal with toxic oxygen-containing molecules is/are
superoxide dismutase AND catalase
A medium that inhibits the growth of organisms other than the one being sought is termed a(n)
selective medium
Bacteria on fish caught in the Arctic Ocean would
be psychrophiles AND continue to grow while the fish is in the refrigerator
Pyruvate can be metabolized along two major routes. They are
fermentation and respiration
The electron transport system
requires a membrane AND generates a concentration gradient of protons
Which of the following processes generates the greatest amount of energy
aerobic respiration
Candle jars are usually used to
provide and atmosphere with CO2
Mercury in mercuchrome inhibits growth
by oxidizing the sulfhydryl groups in cysteine AND by changing the shape of proteins
The most common starting pathway for the breakdown of sugars is
glycolysis
You are working in a clinical laboratory in a hospital setting. ...determining what Gram positive cells might be there. What might you do first to go about working towards this goal?
Perform a Gram stain
Which of the following are obligate aerobes?
Micrococcus luteus
Bacteria may be stored
on a slant in the refrigerator frozen in glycerol solution, AND freeze-dried
Biosynthetic reactions that require energy for the conversion of molecular subunits into larger molecules are called
anabolic reactions
A physician needs a stool sample... lactose fermenting microbes present?
Streak the sample for isolation on a MacConkey agar plate (which contains lactose and a pH indicator that turns pink when acid byproducts are present).
Late log phase of the bacterial growth curve
is marked by the production of secondary metabolites
Chemoheterotrophs
use preformed organic molecules as a carbon source AND as an energy source
MacConkey agar is
a selective and differential agar
The simplest technique for isolating bacteria in growth media is referred to as the
streak-plate method
Quality of the city's water treatment plant.What is the most efficient and cheapest method to determine the # of viable bacteria in the water coming out of your plant?
Using membrane filtration followed by placing the membrane in a growth medium for colony counts after incubation.
Which type of phosphorylation does not require a membrane?
substrate-level phosphorylation
The TCA cycle produces
-ATP
-NADH
-NADH
-Precursor metabolites
X-ALL of the above
During which phase of bacterial growth curve for the total # of viable cells decline?
Death
Organisms that are indifferent to the present of oxygen and do not use it are
aerotolerant anaerobes
Generally the proteins of thermophiles
resist denaturation
The terminal electron acceptor in respiration may be
oxygen, nitrate, AND an inorganic molecule
A hot tub (approx. 104F or 40C) would most likely contain (Quiz 2: #33)
mesophiles
The mutual interaction of substrate and enzyme is described as an
induced fit
The transition step
links glycolysis to the TCA cycle
The name given to the reaction involving removal of electrons or hydrogen atoms from a compound is termed
oxidation
Allosteric enzymes
have an additional binding site that is involved in regulating enzyme activity
Mycobacterium leprae is typically found infecting the ears, toes, and fingers of the host due to its
need for cooler temperatures
A urine sample with 5,000 bacteria with a generation time of 30 minutes sits for 3 hours. How much is present?
320,000
In the cultivation of micoaerophilic and anaerobic bacteria
atmospheric oxygen in a(n) candle/ anaerobe jar is converted to water.
A selective growth medium
allows only certain bacteria to grow
The designation of HIS- refers to
a genotype of bacterium that lacks the functional gene for histidine synthesis AND bacteria that are auxotrophic fot histidine
Fungal diseases are generally referred to as
mycoses
Most fungi are
aerobic or facultatively anaerobic
Direct selection involved inoculating cells onto growth media on which
the mutant but not the parental cell type will grow
The reference for taxonomic descriptions of bacteria is
Bergey's Manual
Serological methods
-are useful in ID'ing bacteria
-rely on the specificity of an anitbody-antigen interaction
-may be simple and rapid
X-ALL of the above
Explain the difference between a biotype and a serotype
A biotype is the biochemical profile, and the serotype is the difference in its surface structures/antigens that will lead to separate immune responses from an organism.
Strain differences are helpful in
tracing the source of outbreaks and disease
Which of the rRNA molecules has proven the most useful in taxonomy/identification?
16S
Mycorrhizae
are vital for the survival of many plants AND increase the absorptive ability of roots
A tangle of fungal hyphae is generally known as
mycelium
Haustoria
are a specialized hyphae used by parasitic fungi
Intercalating agents
act during DNA synthesis AND often result in frameshift mutations
A sample must contain many microorganisms in order to see any using microscopic techniques. Why?
The area on a microscope slide is very large compared to the relative size of microbes, and you take a very small amount of your sample to place on the slide surface. Therefore, you must have a large number of microbes initially in the culture to increase the chances that you'll come across one or more when looking at the slide surface through the magnifying lenses of the microscope
On which of the following DNA strands would UV radiation have the most effect?
AATTAGTTC
The mechanism by which genes are transferred into bacteria via viruses is called
transduction
Which change in a gene's DNA sequence would have the least effect on the eventual amino acid sequence produced from it?
Addition/deletion of three consecutive nucleotides
In conjugation the donor cell is recognized by the presence of
an F plasmid
Why would it be more difficult to treat diseases in humans caused by members of the Eukarya than diseases caused by the Bacteria?
Eukaryotic microbes use many of the same enzymes and systems as humans-so we lose the ability to target certain molecules that might be present ONLY in the cell type we want to eliminate. There's too much overlap when both organisms are eukaryotic.
Dimorphic fungi
may grow as mycelia or yeast AND are often associated with disease in humans.
Chemical mutagens often act by altering the
hydrogen bonding properties of the nucleobase.
The characteristics displayed by an organism in any given environment is its
phenotype
All fungi have ______ in their cell walls.
chitin
In higher organisms, successful mating can occur between members of the same
species
A breath test assaying for radioactive carbon dioxide may be used to indicate the presence of
Helicobacter pylori.
The source of variation among microorganisms that were once identical is
mutation
Streptococcus pyogenes would be
beta hemolytic and catalase negative.
Indirect selection
is necessary to isolate auxotrophic mutants.
Gram-positive encapsulated diplococci found in sputum is indicative of
Streptococcus pneumoniae.
When cellular slime molds run out of food, they form a
slug
A soluble greenish pigment is produced by
Pseudomonas aeruginosa.
Intracellu\lar Gram-negative diplococci found in a urethral sample from a male is indicative of
Neisseria gonorrhoeae.
Why are molecular methods particularly useful for identification of microbes when they are difficult to grow?
Since all microbes use DNA, and we can sometimes detect and identify them through even very small amounts of their DNA, molecular methods allow us to identify microbes even when they can't be grown at all
Organisms that grow very slowly, are non-curable, are present in very small numbers, or are mixed with a number of other bacteria may still be identified using
PCR
Lichens may be an association of
algae and fungus
Media that changes color as a result of the biochemical activity of growing bacteria
usually contain a pH indicator in the media.
Chemical mutagens that mimic the naturally occurring bases are called
base analogs.
X-rays
cause single and double strand breaks in DNA molecules.
Mycobacterium tuberculosis is one of the few species of bacteria that
are acid fast.
Verified questions
engineering
Consider the effect of variable mass on an aircraft landing suspension system by modeling the landing gear as a moving base problem for a car suspension. The mass of a regional jet is 13,236 kg empty and its maximum takeoff mass is 21,523 kg. Compare the maximum deflection for a wheel motion of magnitude 0.50 m and frequency of 35 rad/s for these two different masses. Take the damping ratio to be $\zeta=0.1$ and the stiffness to be $4.22 \times 10^6 N/m.$
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chemistry
What is an atom that has the same number of protons as other atoms of the same element but a different number of neutrons ?
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engineering
The mechanism shown in Figure P6.16 is in equilibrium for an applied load of $P=20 \mathrm{kN}$. Specifications for the mechanism limit the shear stress in the steel $[G=80 \mathrm{GPa}]$ shaft $B C$ to $70 \mathrm{MPa}$, the shear stress in bolt $A$ to $100 \mathrm{MPa}$, and the vertical deflection of joint $D$ to a maximum value of $25 \mathrm{~mm}$. Assume that the bearings allow the shaft to rotate freely. Using $L=1,200 \mathrm{~mm}$, $a=110 \mathrm{~mm}$, and $b=210 \mathrm{~mm}$, calculate (a) the minimum diameter required for shaft $B C$. (b) the minimum diameter required for bolt $A$.
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engineering
Is heat transfer a scalar or vector quantity? Explain. Answer the same question for temperature.
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