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251 Cards in this Set
- Front
- Back
What is an emerging disease?
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A disease that was unknown until recently (about 30 years)
|
|
Name some emerging diseases.
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-AIDS, Flesh eating disease, Anthrax, Food poisoning, Toxic Shock Syndrome, and Lyme Disease.
|
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What is the pathogen that causes AIDS?
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HIV virus
|
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What is the pathogen that causes Flesh eating disease?
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Streptococcus pyogenes
|
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What is the pathogen that causes Anthrax?
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Bacillus anthracis
|
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What is the pathogen that causes Food poisoning?
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E. coli 0157:H7
|
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Explain how microbes play a postive role in oceans and rivers.
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Heterotrophic organisms feed off of bacteria, which are the first link in the food chain.
|
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How do microbes have a positive impact on soil?
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They degrade organic matter (Nitrogen and Phosphorus), which helps to keep the soil fertile.
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How do microbes aid in the digestion processes of animals?
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They use bacteria to break down cellulose (that they could not usually digest) to sugars that they can digest.
|
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Which vitamins to microbes produce?
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-Vitamin B
-Vitamin K |
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Name several chemicals and natural food products that microbes synthesize.
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-yogurt, buttermilk, sour cream, yeast, beer, wine, acetone
|
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Microbes produce recombinant gene products. What does this mean? Give one example.
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They synthesize human proteins in bacteria such as human insulin.
|
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What did John Hooke observe?
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He used a microscope to look at plant cells (the simplest unit of life)
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What was Anton van Leeuwenhoek observation?
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He used a microscope to observe living microbes. He also believed in spontaneous generation.
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What was Francisco Redi's observation?
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He found evidence against spontaneous generation. He excluded air and found the microbes were unspoiled.
|
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What did John Needham do with microbes?
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He used heat and no exclusion from air, which made him pro spontaneous generation.
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What did Spallanzani do with microbes?
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He used heat and exclusion from air, making him against spontaneous generation.
|
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What did Lavoisier question?
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the role of oxygen
|
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What theory did Virchow formulate?
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the biogenesis theory which said that life arises from preexisting life forms.
|
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What did Louis Pasteur do with microbes?
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He excluded air which resulted in an inability of colonization. He resolved in favor of biogenesis.
|
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What did Jenner observe?
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the diary maids who were getting cow pox were not getting small pox.
|
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What did Jenner design based on his observations?
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He designed the first vaccine by taking the fluid from a cow pox blister and purposfully infected people to prevent small pox
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Describe virulent and avirulent viruses and give an example of each.
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Small pox is a virulent disease which is serious and can be lethal. Cow pox is the avirulent disease which a is very mild form.
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What is attenuation?
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The microbe that causes a disease mutates in a test tube and loses virulence, making it inable to cause disease.
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Explain what heat killing does to a microbe.
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When a microbe is heat killed, the outer proteins can be injected to stimulate the immune system.
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Explain fractionation.
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A microbe (or several) is chopped up and the surface protein is extracted. There are no whole microbes to multiply and cause disease
|
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What did Agostino Bassi use to find the first pathogens associated with disease?
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Silk worm disease (fungal)
|
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What did Louis Pasteur use to find the first pathogens associated with disease?
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Silk worm disease (protozoan)
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What was Lister's observation of microbes and what did this result in?
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They cause surgical infection. This observation resulted in the advent of asepsis.
|
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What did Koch contribute to microbiology?
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-Anthrax isolation and culture techniques.
-4 postulates to link microbe to disease (still used today) |
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What did Alexander Fleming discover?
|
Penicillium notatum, which was the first antibiotic. This inhibited bacterial growth.
|
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Where did Rene Dubos extract antibiotics?
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from soil bacteria
|
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What is chemotherapy?
|
the search for chemical substances with selective toxicity
|
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What is the importance of selective toxictiy?
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to make sure the drug is toxic only to the microbe.
|
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Name 3 synthetic drugs and what they were used for.
|
-Arsenic - Syphilis
-Quinine - Malaria -Sulfa drugs - Bacterial infections |
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What are antibiotics? Give 2 examples.
|
Antimicrobial substances produced by microorganisms such as penicillan and streptomyocin.
|
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What are some concerns associated with the used of these drugs?
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-resistance and antiviral agenst.
|
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What is the concern with antibiral agents?
|
In order to kill a virus, we can't use selectively toxic drugs because they are, for now, toxic to our bodies and cells.
|
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What is immunology?
|
the study of immunity
|
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What is virology?
|
the study of viruses
|
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What does recombinant DNA techonlogy have to do with?
|
Genetics and molecular biology.
|
|
what language is used to classify life forms?
|
latin - usually very descriptive, sometimes just the name of the person who discovered the new species.
|
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Who came up with the current system of classification?
|
Linnaeus
|
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What is the name of the TWO NAME SYSTEM used to name life forms?
|
binomial nomenclature
|
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What kind of cells are bacteria and archaea?
|
prokaryotic
|
|
What kingdoms are classified as Eukaryotic?
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Protists, Fungi, Plants, Animals
|
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What is the main difference between prokaryotes and eukaryotes?
|
Prokaryotes have no nuclear membrane to bind nuclear material, whereas eukaryotes have their genetic material bound by a nuclear membrane
|
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Describe a protozoa
|
-single celled
-no cell wall |
|
Describe fungi
|
-cell wall (chitin)
-single or multicelled -complex CHO |
|
Describe plants
|
-multicelled
-cell wall (cellulose) |
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Describe animals
|
-multicelled
-no cell wall |
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what are atoms?
|
the building blocks of living and non-living material
|
|
What are molecules?
|
groups of associated atoms
|
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What is chemistry?
|
the science of atomic interactions
|
|
Describe protons.
|
- +ve charge
-mass about 2000 X electron |
|
Describe neutrons
|
-uncharged
-mass is the same as a proton |
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Describe electrons
|
- -ve charge
-little mass |
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What does the atomic charge being balance and neutral imply?
|
number of protons equals the number of electrons
|
|
What is the atomic number?
|
# of protons
|
|
what is the atomic weight?
|
# of protons plus # of neutrons (~ 2x atomic #)
|
|
What are isotopes?
|
-element family with different atomic weight (different numbers of neutrons)
-stability and abundance may differ |
|
What are electron shells?
|
3D orbitals around the nucleus containing different numbers of electrons. 1st (2), 2nd and 3rd (8), 4th - 6th (18)
|
|
Which shells are filled first?
|
inner shells
|
|
How are stable elements generated?
|
by having full electron shells. atoms will combine to make full shells if possible.
|
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What is elemental reactivity related to?
|
the number of unfilled spaces in outermost orbital
|
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what does valence mean?
|
the number of "gaps" in the outermost shell, an index of combining capacity
|
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What happens to electrons in ionic bonds?
|
electrons are lost by one atom and gained by another.
|
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What creates negative charge and what is it called?
|
gain creates an anion (Cl-, S2-)
|
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What creates a positive charge and what is it called?
|
loss creates a cation (Na+, Ca2+)
|
|
What would stop charged ions from attracting and binding?
|
Other charged molecules coming between them
|
|
What is the role of ions?
|
solubility due to weakness of bond
|
|
What occurs with electrons in a covalent bond?
|
electrons are shared between atoms
|
|
How does the strength of covalent bonds relate to those of ionic bonds?
|
Covalent is a stronger bond
|
|
Where are covalent bonds commonly found?
|
in organic molecules (C and H)
|
|
What forms might you find covalent bonds in?
|
single, double, or triple.
|
|
What kind of bond is common in life forms?
|
hydrogen bonds
|
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What is shared between molecules invovled in a hydrogen bond?
|
hydrogen atoms (protons)
|
|
What atoms, besides hydrogen, are usually involved in hydrogen bonds?
|
oxygen and nitrogen
|
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Relatively speaking, describe the strength and occurence of hydrogen bonds
|
weak, but numerous
|
|
What type of molecules form many hydrogen bonds?
|
water
|
|
What is moleculat weight defined as?
|
The sum of all atomic weights in a molecule
|
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How many molecules does one mole contain?
|
6.02 x 10^23
|
|
What are the 3 main chemical reactions?
|
-synthesis
-decomposition -exchange |
|
describe what happens in a synthesis reaction.
|
small atoms, ions, or molecules combine to form larger molecules
A + B ---> AB reactants ---> product |
|
Does a synthesis reaction require energy?
|
usually
|
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What is formed in a syntheis reaction?
|
new chemical bonds
|
|
what is a syntheis reaction known as?
|
anabolic reaction
|
|
what are synthsis reactions critical in?
|
building body mass and cell division
|
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What occurs in a decompostion reaction?
|
energy is release when larger molucules are broken down to smaller molecules.
AB ---> A + B |
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What happens to the chemical bonds in a decomposition reaction?
|
chemical bonds are broken
|
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What are decomposition reactions also known as?
|
catabolic reactions
|
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What are decompostion reactions critical to?
|
Energy production and tissue breakdown.
|
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What happens in an exchange reaction?
|
AB + CD ---> AD + BC
|
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What might influence the direction of chemical reactions?
|
how stable the products or reactants are.
|
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What must occur for molecules to react with one another?
|
Molecules must collide and they must posess a certain energy level.
|
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What increases the energy level and collision frequency of molecules?
|
Increase in temperature.
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|
What can be used to increase the temperature and stimulate reaction rate?
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-enzymes and catalysts
|
|
what is an enzyme?
|
a protein molecule that assists reactions by acting as catalysts.
|
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What is a catalyst?
|
material that changes the reaction rate w/o being altered itself. It lowers the energy of activations needed before a reaction can proceed
|
|
what purpose to enzyme activities serve in microbiology?
|
enzyme activities can help us to distinguish between microbes and are used to classify them
|
|
what is essential for all life forms?
|
water
|
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What does "polar" mean, in regards to water?
|
the electron (O) has a slight negative charge, and the proton (H) has a slight positive charge
|
|
Why does water have a high boiling point?
|
Because each water moleule forms hydrogen bonds with others causing strong intermolecular forces.
|
|
Why is ice less dense than water, causing it to float and provide insulation?
|
The crystalline bonds in ice are longer than the hydrogen bonds between water molecules.
|
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What does polarity make water a good solvent for?
|
Ionic molecules
|
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What does polarity allow water molecules to assist in?
|
Chemical reactions that require an H+ (acidic) or OH- (basic) group.
|
|
Why is water a good temperature buffer?
|
Strong bonds
|
|
What is an acid?
|
H+ ion donor
HCl --> H+ + Cl- |
|
What is a base?
|
H+ ion acceptor
OH- --> H2O |
|
What is a salt?
|
a substance that dissociates in water to form ions that are neither bases nor acids
NaCl --> Na+ + Cl- |
|
Name some common acids
|
stomach acid, lemon juice, grapefruit juice, wine, urine, milk
|
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Name some common bases
|
seawater, household ammonia and bleach, over cleaner
|
|
Describe the pH scale that measures the Acid / Base balance.
|
<7 = acidic
7 = neutral - pure water (# protons = # base molecule) >7 = basic |
|
What common elements can organic compounds contain
(besides C and H)? |
O, P, S, N
|
|
Describe organic compounds
|
-Carbon framework
-Associated functional groups with differented properties suited to different biological roles |
|
What is a polymer?
|
A combination of small organics that have a repeating chain or branch structure.
|
|
what are the four main classes of polymers?
|
-complex carbohydrates
-lipids -proteins -nucleic acids |
|
What type of polymers are complex carbohydrates?
|
sugar
|
|
What type of polymers are lipids?
|
Fatty acid / glycerol
|
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What type of polymers are proteins?
|
amino acid
|
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What type of polymers are nucleic acids?
|
DNA, RNA nucleotide
|
|
What type of polymer has no charge and includes fatty acids, steroids, and cholesterol?
|
lipids
|
|
What is an important property of lipids and what does it imply?
|
lipids are non-polar so they tend to repel water and form barriers
|
|
name and describe functions of lipids.
|
-membrane components (phospholipid bilayer)
-hormones, signal molecules -energy providers (triglycerides, oils - store) |
|
How much of a cell's dry weight to proteins comprise?
|
50%
|
|
What type of bond joins polymers of amino acids?
|
peptide bonds
|
|
List the functions of protein
|
carrier proteins (hemoglobin), diverse enzyme catalyst, toxins, immune defense (antibodies), movement (actin, flagellin, myosin)
|
|
Describe the secondary structure in Amino Acids.
|
Alpha helix, pleated sheets
|
|
Describe the tertiary structure in Amino Acids.
|
Overall folding of secondary structure
|
|
What is the main distinguishing characteristic of the quarternary structure of Amino Acids?
|
two or more polypeptide chains
|
|
which polymer includes sugars, starches and saccarides?
|
carbohydrates
|
|
what are the functions of carbohydrates?
|
-food reserves (starch, glycogen)
-most "efficient" source of ATP, components in plant, fungal, bacterial cell walls |
|
what are the functions of carbohydrates?
|
-a building block in nucleotide synthesis
-intermediately used for fatty acid and amino acid synthesis |
|
where were nucleic acids first identified?
|
the nucleus of a eukaryotic cell
|
|
what are the units of nucleotides made up of?
|
one sugar, one organic base, and a phosphate group
|
|
What type of polymers are nucleic acids?
|
DNA, RNA nucleotide
|
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What type of polymer has no charge and includes fatty acids, steroids, and cholesterol?
|
lipids
|
|
What is an important property of lipids and what does it imply?
|
lipids are non-polar so they tend to repel water and form barriers
|
|
name and describe functions of lipids.
|
-membrane components (phospholipid bilayer)
-hormones, signal molecules -energy providers (triglycerides, oils - store) |
|
How much of a cell's dry weight to proteins comprise?
|
50%
|
|
What type of bond joins polymers of amino acids?
|
peptide bonds
|
|
List the functions of protein
|
carrier proteins (hemoglobin), diverse enzyme catalyst, toxins, immune defense (antibodies), movement (actin, flagellin, myosin)
|
|
Describe the secondary structure in Amino Acids.
|
Alpha helix, pleated sheets
|
|
Describe the tertiary structure in Amino Acids.
|
Overall folding of secondary structure
|
|
What is the main distinguishing characteristic of the quarternary structure of Amino Acids?
|
two or more polypeptide chains
|
|
which polymer includes sugars, starches and saccarides?
|
carbohydrates
|
|
what are the functions of carbohydrates?
|
-food reserves (starch, glycogen)
-most "efficient" source of ATP, components in plant, fungal, bacterial cell walls |
|
what are the functions of carbohydrates?
|
-a building block in nucleotide synthesis
-intermediately used for fatty acid and amino acid synthesis |
|
where were nucleic acids first identified?
|
the nucleus of a eukaryotic cell
|
|
what are the units of nucleotides made up of?
|
one sugar, one organic base, and a phosphate group
|
|
What are the DNA subunits of nucleic acids called?
|
deoxyribonucleotides
(A, T, C, G) |
|
What are the RNA subunits of nucleic acids called?
|
ribonucleotieds
(A, U, C, G) |
|
what are the functions of nucleic acids?
|
storage of genetic instructions (DNA), expressing genetic instructions (mRNA, tRNA, rRNA), role in energy use (ATP)
|
|
give the division of a meter and standard notation for a decimeter.
|
1/10 m
(10^-1) |
|
give the division of a meter and standard notation for a centimeter.
|
1/100 m
(10^-2) |
|
give the division of a meter and standard notation for a millimeter.
|
1/1,000 m
(10^-3) |
|
give the division of a meter and standard notation for a micrometer.
|
1/1,000,000 m
(10^-6) |
|
give the division of a meter and standard notation for a nanometer.
|
1/1,000,000,000 m
(10^-9) |
|
what is an illuminator?
|
the light source on a microscope
|
|
what is the condenser of a microscope?
|
the lens that directs light up through the sample
|
|
what is the objective on a microscope?
|
the magnifying lens close to the sample
|
|
what is an ocular?
|
the magnifying lens in the eyepiece
|
|
what is total magnification?
|
objective x ocular
|
|
what is resolution?
|
the distance between two points that are distinguisable (wave lenght dependent)
|
|
what are the types of microscopy?
|
brightfield, darkfield, phase contrast, differential interference contrast, fluorescence
|
|
what type of microscopy uses visible light illumination and is best for stains?
|
brightfield
|
|
what type of microscopy reflects light off the specimen which is seen against a dark backgroud?
|
darkfield
|
|
Differences in the way cell regions refract light allow unstained microbes to be viewed alive describes what type of microscopy?
|
phase contrast
|
|
What type of microscopy is more useful for eukaryotic cells and shows variations as differenct brightness levels?
|
phase contrast
|
|
what type of microscopy is similar to phase contrast, but has better resolution, 3D image and color, and uses 2 light beams?
|
differential interference contrast
|
|
Which type of microscopy uses short UV wavelength to excite fluorescent dyes which emit longer wavelength colored light?
|
fluorescence
|
|
Do some fluorochromes have an affinity for specific molecules?
|
yes
|
|
What are the two types of electron microscopy?
|
transmission (TEM) and scanning (SEM)
|
|
What type of lenses are used to focus x-rays with electron microscopy?
|
electromagnetic
|
|
what is the resolution used with electron microscopy?
|
high (2.5 nm)
|
|
What does electron microscopy permit the viewing of?
|
internal cell contents or ultrastructure
|
|
What type of electron microscopy uses thin sections stained with heavy metal salts?
|
Transmission electron microscopy
|
|
What type of electron microscopy shows 3D views of specimen surfaces or profiles?
|
scanning electron microscopy
|
|
what is the resolving power of scanning electron microscopy?
|
around 20 nm
|
|
which type of electron microscopy is more detailed?
|
transmission electron microscopy
|
|
Which type of electron microscopy allows samples to be freeze fractured, coated with carbon or gold?
|
scanning electron microscopy
|
|
what does fixing do to microbes?
|
it attaces the permanently to a surface for viewing
|
|
what process fix most microbes?
|
air drying (15-20 min) and heat.
|
|
what is a thin spread of microbes of glass called?
|
smear
|
|
what is the process that colorizes microbes with a dye that emphasizes particular structures called?
|
staining
|
|
describe how a stain works.
|
the stains for ionic bonds with oppositely charged molecules on cells
|
|
what is known as a chromophore?
|
a colored salt ion
|
|
what type of dyes are used to view bacteria and why?
|
basic dyes because bacteria have a negative surface charge.
ex: Crystal violet, Saffranin, Methylene blue |
|
When are acidic dyes used for bacteria? Give some examples of acidic dyes.
|
dyes such as Eosin and India Ink are used to Negatively staining bacteria.
|
|
what is the method for the gram stain?
|
-heat fix smear on slide
-apply Crystal Violet -wash off excess dye (water) -add Iodine(color intensifyer) -wash of excess idoine (water) - |
|
What are the steps of gram staining after Gram +ve and Gram -ve are both stained purple.
|
-wash slide with ethanol or alcohol/acetone
-rinse off solvent with water |
|
What is the last step of preparing Gram stain slides and what is the result?
|
-apply a counterstain of safranin which leaves only the Gram -ve cells pink.
|
|
What happens inside the bacterial cell (gram stain)?
|
Crystal violet and iodine form a CV-I complex of a dark purple color which cannot wash out of the thick cell wall of GRAM +ve
|
|
What is the outer covering of Gram negative bacteria?
|
lipopolysaccharide
|
|
What does the alcohol wash do to the outer covering of the Gram negative bacteria?
|
it disrupts the outer covering and the colored CV-I complex is washed out.
|
|
Do all bacteria stain using the Gram method?
|
NO
|
|
What type of bacteria does the Gram method work best on?
|
rapidly dividing bacteria
|
|
What does the Gram reactivity of bacteria assist in?
|
The treatment of disease
|
|
What are Gram positive bacteria usually killed by?
|
Penicillin and Sulfa drugs
|
|
What type of drugs are Gram negative bacteria more susceptible to and why?
|
Streptomycin and Tetracycline because they target protein synthesis
|
|
How does an ACID-FAST stain work?
|
It binds preferentially to bacteria with a waxy material in their cell walls.
|
|
What genus does the ACID-FAST stain identify?
|
Mycobacterium, which includes TB and Leprosy
|
|
What is a NEGATIVE stain used for?
|
to look for bacterial capsules (simple stain does not show capsules)
|
|
How do the capsules around a bacterium affect antibiotics?
|
They can affect the ability of the antibiotic to penetrate and kill a bacterial cell
|
|
How can NEGATIVE staining be used in conjunction with a simple stain?
|
neg. stain can provide a halo-like effect around a thick capsule. simple stain will allow ID of bacterium lying within the capsule
|
|
What is a distinguishing factor of a virulent bacteria's capsule?
|
it is thicker.
|
|
How is the genetic material stored in a prokaryotic cell?
|
in a nucleoid. prokaryotes do not have a nucleus.
|
|
where is the genetic material of eukaryotes found?
|
enclosed in a nuclear membrane
|
|
What is the difference between eukaryotic and prokaryotic choromosomes?
|
prokaryotes: circular
eukaryotes: linear |
|
What is the difference between eukaryotic and prokaryotic organelles?
|
prokaryotes: non membranous
eukaryotes: in cytoplasm |
|
What is the difference between eukaryotic and prokaryotic histones?
|
Prokaryotes: no histone proteins
Eukaryotes: highly conserved histones, compact DNA |
|
What is the difference between eukaryotic and prokaryotic cell walls?
|
Prokaryotes: almost all contain peptidoglycan
Eukaryotes: may be present -chitin - fungi -cellulose - plants |
|
What is the difference between eukaryotic and prokaryotic reproduction?
|
-prokaryotes: binary fission, no mitotic spindle
-eukaryotes: mainly sexual, mitotic spindle aids DNA segregation |
|
What is the size of a prokaryotic cell?
|
2 - 8 micrometers in length
|
|
what are the basic shapes of prokaryotes?
|
-cocci: sphere
-bacilli: rods -spirals |
|
what are the subdivisions and names of a cocci shape?
|
pairs - diplococci
chains - streptococci groups of four - tetrads clusters - staphylococci |
|
what are the subdivisions and names of the bacilli shape?
|
-pairs - diplobacilli
-chains - streptobacilli -short rods (E. coli) - coccobacilli |
|
What are the subdivisions and names of the spiral shapes?
|
-curved rods - vibros
-rigid corkscrews - spirilla -flexible corkscrews - spirochetes |
|
what are other shapes of prokaryotic cells?
|
-star shapes- stella
-flat squares - haloarcula |
|
Describe the GLYCOCALYX of a prokaryote's cell wall.
|
The glycocalyx is a sticky polymer outside the cell wall. It is either a polysaccharide or peptide.
|
|
What is the firm attachment of the glycocalyx called?
|
capsule - does not detach
|
|
What is the loose attachment of the glycocalyx called?
|
slime layer - will detach from bacteria
|
|
List the functions of the glycocalyx.
|
escape phagocytosis and attachment to environmental surfaces
|
|
list the arrangements of flagella
|
-polar
-single or multiple -all over the cell |
|
Describe flagella of a prokaryotic cell.
|
Long filamentous structures that propel bacteria
|
|
Name and describe the two types of propulsion of flagella.
|
-chemotaxis (chemical stimuli) is a tumbling motion.
-phototaxis ("light" stimuli) causes the bacteria to head straight for the light |
|
Describe axial filaments of a prokaryotic cell.
|
-similar to flagellae in structure and function
|
|
What is the main difference between axial filaments and flagella?
|
axial filaments are found only on Spirochetes
-Treponema pallidum (Syphilis) -Borrhelia burgdorferi (Lyme Disease) |
|
Describe fimbriae and pili.
|
-Thin, short, straight hair-like appendages.
-used for attachment only -few to several hundred -can be polar or all over cell |
|
What are PILI specifically used for in regards to bacteria?
|
They join the bacteria in preparation for the transfer of DNA from one bacerial cell to another (conjugation)
|
|
What are the functions of the prokaryote's cell wall?
|
-protects underlying plasma membrane and cytoplasm against osmotic effects
-provides attachment points for flagella |
|
What are the functions of the prokaryote's cell wall?
|
-maintains the cell shape
-can contribute towards disease process -can be acted upon by antibiotics |
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What is the main difference between eukaryotic and prokaryotic cell walls?
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the prokaryote has a more complex and rigid structure
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Describe the prokaryote's gram positive cell wall.
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-thicker peptidoglycan layer
-polysccharides in cell wall -teichoic acids in cell wall |
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What do the polysaccharides in the cell wall of a prokaryotic gram positive cell do?
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they group the bacteria into medically significant subgroups (Mycolic Acid)
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What do the terichoic acids in the cell wall of a gram positive prokaryotic cell do?
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-protect against cell wall rupture
-antigenic, permit serological classification of bacteria |
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Why are gram negative prokaryote cell walls negatively charged and what role does that play in phagocytosis?
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-neg. charge due to phosphate groups on phospholipids
-evade phagocytosis |
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What is the purpose of a gram negative cell wall's second outer lipid membrane?
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-barrier to some antibiotics
-digestive enzymes -detergents -heavy metals -bile salts and dyes |
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What are the protein channels in gram negative cell walls made of and what do these channels allow?
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-made of porin proteins
-allow movement of molecules in and out. |
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Where is there a very thin layer of peptidoglycan in gram negative cell walls?
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the periplasmic space
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What is contained in a gram negative cell wall's periplasmic space?
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a high concentration of degradative enzymes and transport proteins
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How do gram negative cells walls acquire antigenicity?
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they have no teichoic acids, but the polysaccharides provide antigenicity
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what is serology?
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the study of antigens
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what is the plasma membrane of a prokaryotic cell made up of?
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-phospholipids and proteins
-phospholipid bilayer -embedded proteins |
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Describe selective permeability
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depends on size and charge of molecule trying to pass through. small, uncharged, or polar molecules can readily pass through membrane
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What two processes occur in the plasma membrane of a prokaryote?
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diffusion and active transport
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what does the nucleoid of a prokaryote contain?
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the bacterial DNA chromosome
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what is the function of a prokaryotic ribosome?
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-protein synthesis
-contain protein and RNA components |
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What are endospores?
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-resistant thick walled forms of Bacillus and Clostridium species
-highly dehydrated -contain dipicolinic acid |
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What does the "vegetative state" of enospores refer to?
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the endospre is metabolically active.
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How does an endospore return to the vegetative state?
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Through germination
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