Microbiology Book Flashcards
_______________ are organisms whose cells contain a nucleus, composed of genetic material surrounded by a distinct membrane
Eukaryotes
_______________ are unicellular microbes that lack a true nucleus
Prokaryotes
__________ are relatively large microscopic eukaryotes and include molds and yeasts. These organisms obtain their food from other organisms and have cell walls.
Fungi
___________ are single-celled eukaryotes that are similar to animals in their nutritional needs and cellular structure. Most part capable of Locomotion, and some cause disease.
Protozoa
__________ are plant like eukaryotes that are photosynthetic ; they make their own food from carbon dioxide and water, using energy from sunlight
Algae
__________ are unicellular prokaryotes who’s cell walls are composed of peptidoglycan. Most are beneficial, but some cause disease.
(some lack cell walls)
Bacteria
__________ are single celled prokaryotes have a cell walls lack peptidoglycan and instead are composed of other polymers
Archaea
__________ are microorganisms so small that they were hidden from microbiologist until the invention of the electron microscope in 1932. All are acellular obligate parasites.
Viruses
The theory of ___________________ proposes that all living organisms can arise from nonliving matter
(Louis Pasteur use the swan neck flask’s that remained free of microbes, disproving the theory)
Spontaneous generation
Abiogenesis
Microbes are intentionally manipulated to manufacture products
Industrial microbiology
Biotechnology
________________ is the use of heat to kill pathogens and reduce the number of spoilage microorganisms in food and beverages, is an industrial application widely used today.
Pasteurization
The sum of all chemical reactions in an organism
Metabolism
Microorganisms that cause specific diseases are called ______________
Pathogens
____________________
1. The suspected causation agent must be found in every case of the disease and be absent from healthy hosts.
2. The agent must be isolated in grown outside the host.
3. When the agent is introduced to a healthy susceptible host, the host must get the disease
4. The same agent must be re-isolated from the disease, experimental host.
Koch’s postulates
The _____________ is the most widely used staining technique and distinguishes gram-positive from gram-negative bacteria, and reflects differences in composition of the bacterial cell wall
Gram stain
- developed by Christian Gram a danish scientist in 1884
_______________ infections acquired from unclean & unhygienic healthcare facilities
Nosocomial
The study of the occurrence, distribution, and spread of disease in humans
Epidemiology
The study of the body’s specific defenses against pathogens
Immunology
A branch of medical microbiology, in which chemicals are studied for their potential to destroy pathogenic microorganisms
Chemotherapy
________________ is the study of metabolism
Biochemistry
_______________ combines aspects of bio, chemistry, cell biology, and genetics to explain cell function at the molecular level
Molecular biology
________________ involves the manipulation of genes in microbes, plants, animals for practical applications, such as the development of pest-resistant crops in the treatment of disease
Genetic engineering
_______________ is the use of recombinant DNA to insert a missing gene or repair a defective gene in human cells
Gene therapy
_______________ studies the role microorganisms play in their natural environment
Environmental microbiology
_____________ is the study of blood serum, the liquid that remains after blood coagulates, and which carries disease fighting chemicals
Serology
Which microbial group was not discovered until the introduction of modern research tools?
A. Archaea
B. Bacteria
C. Fungi
D. Viruses
A
Early scientists used the term fermentation to mean:
A. The formation of alcohol.
B. The formation of acids.
C. The putrefaction of meat.
D. All the above.
D
The germ theory of disease specifically applies to:
A. All diseases.
B. Genetic diseases.
C. Infectious diseases.
D. Diseases caused by toxins or allergies.
C
Koch’s Postulates are ultimately successful for eating scientists and discovering the causes of infections diseases because of what laboratory technique?
A. Isolation of organisms in pure culture.
B. Observation of organisms under microscopy
C. Staining techniques, such as the Gram stain.
D. Methods for counting the numbers of organisms present in a sample.
A
The Gram stain is useful for distinguishing between which types of microbes?
A. Algae.
B. Bacteria.
C. Fungi.
D. Protozoa.
Bacteria
Which of the following questions was not answered during the golden age of microbiology?
A. Does life spontaneously generate?
B. Do microbes cause fermentation?
C. Does microbial life exist on other planets?
D. Do microbes cause disease?
C
Which of the following is not a role that microbes play in the environment?
A. Causing disease.
B. Decaying dead organisms.
C. Recycling chemicals.
D. All our roles played by microbes.
D
____________ what is defined as anything that takes up space and has mass
Matter
The smallest chemical unit of matter are ___________
Atoms
Negatively charged particles that spin around the nucleus are called _______________
Electrons
Uncharged particles in the nucleus are called _______________
Neutrons
Positively charged particles in the nucleus are called ______________
Protons
An ____________ is matter that is composed of a single type of atom
Element
_______________ is the number of protons in the nucleus
Atomic number
________________ is the sum of the masses of its protons, neutrons and electrons
Atomic mass
Atomic weight
______________ are atoms of an element that differ only in the number of neutrons they contain
Isotopes
The outer most shell of an atom is called the ______________
Valence shell
The number of electrons in the valence shell of an atom determines the atom’s ______________
Reactivity
- Atoms with valence shells not containing the maximum number of electrons are more likely to give up or accept electrons from another atom until the outermost shell is full
Sharing or transferring of electrons to fill a valance shell results in the formation of a _________________
Chemical bond
2 or more atoms held together by chemical bonds form a ______________
Molecule
Molecule containing atoms of more than one element is called a ________________
Compound
A _______________ is the sharing of a pair of electrons by two atoms
Covalent bond
Attraction of an atom for electrons is called its __________________
Electronegativity
____________________ form when atoms with similar electronegativities bind, and the shared electrons tend to spend an equal amount of time around each nucleus of the pair (neither nucleus acts as a pole to exert an unequal pole)
Nonpolar covalent bonds
_______________ form when atoms with significantly different electronegativities combine, and the electron pair will spend more time orbiting the nucleus of the atom with greater electronegativity (causing an unequal sharing of electrons)
Polar covalent bonds
Compounds that contain carbon and hydrogen atoms are called _________________
Organic compounds
Charged atoms are called ________
Positively charged atoms are called ________
Negatively charged atoms are called ________
Ions
Cations
Anions
The opposite charges of cations and anions attract each other strongly to form an _______________
Ionic bond
Molecules with ionic bonds form crystalline compound, known as _______ (such as sodium chloride)
Salts
In ionic bonds, the electrons are _____________ from one molecule to another
Transferred
The polar bonds of water molecules interfere with a ionic bonds of salt, causing _________________
Dissociation (ionization)
When cations and anions dissociate in water, they are called _____________ because they can conduct electricity through the solution
Electrolytes
_____________ form when a partially charged hydrogen atom is attracted to a full or partially negative charge on either a different region of the same molecule or another molecule. The cumulative effect of numerous hydrogen bonds is to stabilize the three dimensional shapes of large molecules, such as DNA.
Hydrogen bonds
_______________ result from the making or breaking of chemical bonds
Chemical reactions
Atoms, ions, or molecules that exist at the beginning of a reaction
Reactants
Atoms, ions, or molecules that remain after the reaction is complete
Products
_______________ involve the formation of larger, more complex molecules
Synthesis reactions
___________________ , is when 2 smaller molecules are joined together by a covalent bond and a water molecule is removed from the reactants
Dehydration synthesis
_______________ is the sum of all the synthesis reactions in an organism
Anabolism
Reactions that trap energy within a new molecular bonds
Endothermic reactions
____________________ break bonds within larger reactants to form smaller atoms, ions, and molecules
Decomposition reactions
Reactions that release energy are called ____________________
Exothermic reactions
_______________ is a common type of decomposition reaction, in which a covalent bond in a large molecule is broken and the ionic components of water (H+ & OH-) are added to the products
Hydrolysis
All of the decomposition reactions in an organism are called _________________
Catabolism
_______________ involves exchanging atoms between reactants
Exchange reactions
The sum of all chemical reactions in an organism is called ______________________
Metabolism
_______________ lack carbon
Inorganic chemicals
An ________ is a substance that dissociates into 1 or more hydrogen ions and 1 or more anions
Acid
A __________ is a molecule that binds with H+ when dissolved in water, and many may dissociate into hydroxyl ions and cations.
Base
The concentration of hydrogen ions in a solution is expressed using a logarithmic _______ scale in which acidity increases as the values decrease
pH
Organisms can tolerate only a narrow pH range and most organisms contain natural __________ , which are substances that prevent drastic changes in internal pH
Buffers
A ______ is a compound that dissociates in water into cations and anions, other than H+ & OH-
Salt
__________________ are large complex molecules containing carbon and hydrogen atoms linked together in branched and unbranched chains, and rings bound to one or more other elements, such as oxygen, nitrogen, phosphorus, or sulfur.
Organic macromolecules
In organic macromolecules, atoms often appear in certain common arrangement called _____________
Functional groups
The organic macromolecules of proteins, carbohydrates, and nucleic acids are composed of simple subunits called ____________ that can be covalently linked to form chain like _____________ , which may be hundreds of thousands long
Monomers
Polymers
__________ are organic macromolecules composed most entirely of carbon and hydrogen atoms linked by nonpolar covalent bonds
Lipids
Insoluble in water
Hydrophobic
Lipophilic
The 4 major groups of lipids are :
____________
____________
____________
____________
Fats
Phospholipids
Waxes
Steroids
________ are composed of glycerol and three chain like fatty acids
Fats
True or false: saturated fatty acids contain more hydrogen in there structural formulas than unsaturated fatty acids, which contain double bonds between some of their carbon atoms
True
_________________ contain two fatty acid chains and a phosphate functional group.
Phospholipids
__________ contain one long fatty acid linked covalently to a long chain alcohol by an ester bond (they are completely water insoluble and are sometimes used as energy storage molecules)
Waxes
____________ consist of four-carbon rings that are fused to one another and attached to various side chains and functional groups (many organisms have sterol molecules in their cell membranes that keep them fluid at low temperatures)
Steroids
_______________ are organic molecules composed solely of atoms of carbon, hydrogen, and oxygen. They are used for immediate and long-term storage of energy, as structural components of DNA and RNA and some cell walls, and for conversion into amino acids. They also serve as recognition sites during intercellular interactions.
Carbohydrate
The 3 basic groups of carbohydrates :
_______________
_______________
_______________
Monosaccharides
Disaccharides
Polysaccharides
_______________ are simple sugars, such as glucose and fructose. They usually take cyclic forms
Monosaccharides
_______________ are formed when two monosaccharides are linked together via dehydration synthesis. Sucrose, lactose, and maltose are examples.
Disaccharides
_______________ are polymers composed of tens or thousands of monosaccharides that have been covalently linked in dehydration synthesis reactions. Cellulose and glycogen are examples.
Polysaccharides
The most complex organic macromolecules are ___________ , which are composed mostly of carbon, hydrogen, oxygen, nitrogen, and sulfur. They function as structural components of cells enzymatic catalysts, regulators of various activities, transporters of substances, and defense molecules.
Proteins
The monomers of proteins are ___________ , in which a central carbon is attached to an amino group, a hydrogen atom, a carboxyl group, and a side group that varies according to the amino acid.
Amino acids
True or false: every protein has at least 3 levels of structure, and some have 4
True
Monomers of proteins are linked together by _____________ into specific structural patterns determined genetically
Peptide bonds
_______________ of a protein disrupt its structure and subsequently its function
Denaturation
The two nucleic acids are ______________________ & _____________________ , which comprise the genetic material of cells and viruses
Deoxyribonucleic acid & ribonucleic acid
Monomers of nucleic acids are called ___________
Nucleotides
True or false : each nucleotide consist of phosphoric acid, a pentose sugar (deoxyribose, or ribose), and one of the five cyclic nitrogenous bases (adenine, guanine, cytosine, thymine, and uracil)
True
DNA contains ____ , ____ , ____ , & ____ nucleotides
A
G
C
T
RNA contains ____ , ____ , ____ , & ____ nucleotides
A
G
C
U
True or false: the structure of nucleic acids allows for genetic diversity, correct copying of genes for their passage on to the next generation, and the accurate synthesis of proteins
True
_______________ which is made up of the nitrogenous base adenine, ribose, sugar, and three phosphate groups is the most important short term energy storage molecule in cells. It is also incorporated into the structure of many coenzymes.
Adenosine triphosphate (ATP)
Which element has the greatest number of protons in its nucleus?
A. Carbon 12.
B. Carbon 13.
C. Carbon-14.
D. All have the same number of protons.
D
A nonpolar covalent bond:
A. Shares electrons equally between atoms
B. Shares electrons unequally between atoms.
C. Forms are in one atom strips the valence electrons from another atom.
D. Does not form between the electrons of different atoms.
A
Which of the following acid is an organic acid?
A. HNO3
B. HCl
C. CH3COOH
D. H3PO4
C
Salts are held together by what type of bonds?
A. Non-polar covalent bonds.
B. Polar covalent bonds.
C. Ionic bonds.
D. Hydrogen bonds.
C
Exchange, or transfer reactions, are:
A. endothermic.
B. Exothermic.
C. Both endothermic and exothermic.
D. Neither endothermic nor exothermic.
C
Lemon juice, with a pH of 2, contains how many more hydrogen atoms in milk with a pH of 6?
A. 10 times.
B. 100 times.
C. 1000 times.
D. 10,000 times.
D
Which of the following is not considered a macromolecule?
A. DNA.
B. Sucrose.
C. Phospholipids.
D. Antibodies.
B
Lipids are composed almost entirely of carbon and hydrogen atoms together by :
A. Nonpolar covalent bonds.
B. Polar covalent bonds.
C. Ionic bonds.
D. Hydrogen bonds.
A
What type of fatty acids would you expect to see predominating in the membranes of microbes, a living in extremely hot environments?
A. Saturated fatty acids
B. Unsaturated fatty acids.
C. Polyunsaturated fatty acids.
D. All types of fatty acids would be present an equal amount.
A
The cell walls of bacteria are made out of what materials?
A. Monosaccharides and amino acids.
B. Polysaccharides and amino acids.
C. Monosaccharides and lipids.
D. Polysaccharides and lipids
B
The most abundant polysaccharide on earth is?
A. Amylose
B. Cellulose
C. Glucose.
D. Glycogen.
B
Which of the following is not a function of nucleic acids?
A. Nucleic acids carry the genetic instructions of the cell
B. Nucleic acids are involved in protein synthesis.
C. Nucleic acids provide energy for cellular functions.
D. All of these are functions of nucleic acids.
C
All living things share for processes :
_______________
_______________
_______________
_______________
Growth : an increase in size
Reproduction : an increase in number
Responsiveness : an ability to react to environmental stimuli
Metabolism : controlled chemical reactions
____________ cells such as bacteria and archaea, lack a nucleus and membrane bound organelles
Prokaryotic
____________ cells such as the cells of animals, plants, algae, fungi, and protozoa, have internal membrane bound organelles, including true nuclei
Eukaryotic cells
A _______________ is a gelatinous, sticky substance that surrounds the outside of the cell
Glycocalyx
When the glycocalyx of a prokaryote is firmly attached to the cell surface, it is called a __________
Capsule
And when the glycocalyx of a prokaryote is loose and water soluble, it is called _____________
Slime layer
____________ are long, would like extensions from the cell surface and glycocalyx that propel a cell throughout its environment (cell motility)
Flagella
_______________ are the special flagella of spirochetes that spiral tightly around the cell instead of protruding into the environment
Endoflagella
Via __________ , the flagella move the cell toward or away from stimuli such as chemicals (chemotaxis) or light (phototaxis)
Taxis
__________ are short, sticky, proteinaceous, nonmotile extensions of some bacteria that help cells adhere to one another and to substances in the environment (serve as biofilms, slimy masses of bacteria adhering to a surface)
Frimbriae
________ are hollow, nonmotile tubes of a protein called pilin that connect some prokaryotic cells
Pili
Most prokaryotic cells are surrounded by a ____________ that provides structure and protection from osmotic forces (they are composed of polysaccharide chains)
Cell wall
A few bacteria lacks cells entirely, but most have walls composed of ______________ (a complex polysaccharide composed of two alternating sugars called N-acetylglucosamine [NAG] & N-acetylmuranic acid [NAM])
Peptidoglycan
_______________ cells have thick layers of peptidoglycan that also contain teichoic acids. Their thick wall retains the crystal violet dye used in the gram staining procedure, so the stand cells appear purple under magnification.
Gram-positive
_____________ cells have only a thin layer of peptidoglycan, outside of which is a bilayer membrane, composed of phospholipids, channel proteins, lipopolysaccharide (LPS) , which contain lipid A. Between the peptidoglycan, and the bilayer membrane is a periplasmic space. After the gram staining procedure, gram-negative cells appear pink.
Gram-negative
True or false: archaeal cell walls lack peptidoglycan
True
The _______________ cytoplasmic membrane not only separates the contents of the cell from the outside environment, but also controls the contents of the cell, allowing some substances to cross it, while preventing the movement of others
Selectively permeable
_______________ is the movement of chemicals down there, concentration gradient, from an area of higher concentration to an area of lower concentration
Simple diffusion
In _______________ , proteins act as channels or carriers to allow certain molecules to diffuse into or out of the cell along their electrochemical gradient
Facilitated diffusion
_______________ is the diffusion of water molecules across a selectively permeable membrane in response to different concentrations of solutes
Osmosis
2 solutions that have the same concentration of solutes are said to be ____________
Isotonic
A solution that has a higher concentration of solutes than another, is said to be __________
Hypertonic
A solution that has a lower concentration of solutes, it said to be ___________
Hypotonic
_______________ moves substances via carrier proteins which may transport two substances in the same direction at once (symports), or move substances in opposite directions (antiports)
Active transport
_______________ causes chemical changes to the substance being transported. The membrane is impermeable to the altered substance, which is been trapped inside the cell. One well studied example is the phosphorylation of glucose.
Group translocation
_____________ is the semiliquid, gelatinous, elastic material inside a cell, and is composed of cytosol, inclusions, ribosomes, and a cytoskeleton
Cytoplasm
The liquid portion of the cytoplasm is called the ____________ (composed of mostly water, ions, carbohydrates, proteins, lipids, and wastes)
Cytosol
Deposits called _____________ maybe found within the cytosol of prokaryotes and maybe reserve deposits of lipids, starch, gas, or other chemicals
Inclusions
2 types of non-membranous organelles that are found in direct contact with the cytosol of prokaryotes are _______________ & _______________
Ribosomes
Cytoskeleton
_____________ are the sites of proteins synthesis in cells
Ribosomes
The ____________ is an internal network of fibers that appear to form a cells basic shape
Cytoskeleton
True or false: spherical prokaryotes appear to lack cytoskeleton’s
True
The shaft of a eukaryotic flagella them is composed of molecules of a globular proteins called ___________ arranged in chains to form hollow ____________ arranged in 9 pairs around a central 2
Tubulin
Microtubules
Some eukaryotic cells are covered with ________ , which have the same structure as eukaryotic flagella what are much shorter and more numerous
Cilia
The cell walls of plants are composed of _______________
Cellulose
Fungal cell walls are composed of _____________
Chitin
________ cell walls are composed of agar, carrageenan, algin, & other chemicals
Algal
An active process, requiring the expenditure of energy by the cell to transport substances into the cytoplasm and is a process called ______________
Endocytosis
In endocytosis, the movable extensions of the cytoplasm in membrane of the cell, that surround a substance, and move it into the cell are called __________________
Pseudopodia
When solids are brought into the cell, endocytosis is called ________________
Phagocytosis
When liquids are brought into the cell, endocytosis is called ________________
Pinocytosis
3 non-membranous organelles found in eukaryotes are ___________ , __________ & __________
Ribosomes
Cytoskeleton
Centrioles
The __________ is spherical or ovoid, and the larger organelle that consists of DNA
Nucleus
2 centrioles, lying at right angles to each other, near the nucleus, in a region of the cytoplasm, called the _______________
Centrosome
______________ are composed of 9 triplets of microtubules, and appear to play a role in mitosis, cytokinesis, and in the formation of flagella and cilia
Centrioles
The semi liquid matrix of the nucleus is called the _____________
Nucleoplasm
____________ , a thread-like mass of DNA & associated histone proteins
Chromatin
Chromatin becomes visible as chromosomes during ____________
Mitosis
Surrounding the nucleus is a double membrane, called the nuclear envelope, which contains ________________ that function to control the import and export of substances through the envelope
Nuclear pores
Continuous with the outer membrane of the nuclear envelope and transversing the cytoplasm in a net of hollow tubules called _______________
Endoplasmic reticulum
ER
____________ endoplasmic reticulum plays a role in lipid synthesis and transport
Smooth
Ribosomes adhere to the surface of ___________ endoplasmic reticulum, and produce proteins that are transported throughout the cell
Rough
The _______________ is a series of flattened, hollow sacs, surrounded by phospholipid bilayer‘s. It receives, processes, and packages large molecules in secretory vesicles which release their contents from the cell via exocytosis.
Golgi body
Complex
Apparatus
___________ are membranous sacs that store or carry substances
Vesicles
Vacuoles
_______________ contains digestive enzymes that damage the cell if they are released from their packaging into the cytosol
Lysosomes
____________ are vesicles that contains oxidase and catalase, enzymes that degrade, poisonous metabolic wastes, such as free radicals in hydrogen peroxide (found in all eukaryotic cells, but are prominent in the liver and kidney cells)
Peroxisomes
_______________ are light harvesting structures found in photosynthetic eukaryotes. They are pigments gather light energy to produce ATP andforms sugar from carbon dioxide.
Chloroplasts
_______________ refers to the use of light or electrons to magnify objects
Microscopy
Various forms of radiation differ in ____________ , which is the distance between 2 corresponding parts of a wave
Wavelength
_______________ is the apparent increase in size of an object and is indicated by a number followed by an “x” which reads as “times”
Magnification
___________ is the ability to distinguish between objects that are close together
Resolution
Also called : resolving power
_______________ is used to fill space between the specimen and a lens to reduce light refraction and thus increase the numerical aperture and resolution
Immersion oil
_______________ refers to differences in intensity between 2 objects or between an object and its background
Contrast
Most common microscopes are _______________ , in which the background is illuminated
Bright-Field microscopes
2 basic types of bright-field microscopes are _______________ & _______________
Simple microscope
Compound microscope
The _______________ of a compound microscope is determined by multiplying the magnification of the objective lens by that of the ocular lens
Total magnification
Pale objects are best observed with ________________ , which utilize a dark-field stop in the condenser that prevents light from directly entering the objective lens
Dark-field microscopes
_______________ use a phase plate to retard light rays passing through the specimens, so that they are 1/2 wavelength out of phase with neighboring light waves, thereby producing contrast
Phase microscopes
_______________ use an ultraviolet light source to fluoresce objects
Fluorescent microscope’s
_______________ use fluorescent dyes in conjunction with the UV lasers to illuminate the fluorescent chemicals in only one thin plane of a specimen at a time
Confocal microscopes
