CH. 25 Practice Quiz
The set of guidelines known as ________ are used to demonstrate that a specific pathogen causes specific disease symptoms.
Koch's postulates
Prokaryotic cells are distinguished from eukaryotic cells by:
a circular genome, absence of a nuclear envelope, absence of mitochondria
many prokaryotes have
a slime layer, outer layers made of polysaccharide/protein, a capsule
Spherical prokaryotes are called ____________ they may occur in pairs called ____________ in chains called _________ or in clumps or bunches called __________.
cocci, diplococci, streptococci, staphylococci
Conjugation
contributes to genetic variation, occurs in bacteria, is an example of horizontal gene transfer
During photosynthesis, ________ fix large amounts of carbon dioxide into organic molecules.
cyanobacteria
Prokaryotes and fungi are nature's primary ________.
decomposers
________ obtain their energy from dead organic matter.
decomposers
Pathogens are microorganisms such as bacteria, fungi, and protists that cause ________.
disease
In some ways, archaea are actually more like ______ than bacteria.
eukaryotes
Bacterial flagella:
exhibit rotary motion
Archaea that require either a very high or a very low temperature for growth are considered to be ________.
extreme halophiles
Archaea that require either a very high or a very low temperature for growth are considered to be ________.
extreme thermophiles
Prokaryotes use a rotating ___________ consisting of a basal body, a hook, and a single filament as their main method of movement. Movement of bacteria in response to chemicals in the environment is called ___________. .
flagella, chemotaxis
Prokaryote taxonomy is now based largely on molecular data, RNA sequencing and more recently on ________.
genome sequencing
prokaryote taxonomy relies on
genomic sequencing, RNA sequencing, molecular data
Bacteria that do not retain the stain when rinsed with alcohol are called _________________ bacteria.
gram-negative
Bacteria that absorb and retain crystal violet stain are referred to as _______________ bacteria.
gram-positive
Penicillin works most effectively against _______________ bacteria because it interferes with _______________ synthesis.
gram-positive, peptidoglycan
The majority of bacteria are: Autotrophs, photosynthesizers, heterotrophs, pathogens, anaerobes
heterotrophs
Prokaryotes
may transfer genetic information horizontally, may have fimbriae, may be gram-positive, are cellular organisms
____________ are a group of archaea that inhabit oxygen-free environments such as sewage or swamps
methanogens
The community of harmless bacteria that inhabit the surface of the human skin is called a ________.
microbiota
Peptidoglycan is a chemical compound found in the cell walls of:
most bacteria
Because bacteria reproduce by binary fission, ________ are quickly passed on to new generations, and natural selection effects are quickly evident.
mutations
The three types of symbiotic relationships that can be observed when prokaryotes interact with other organisms are ________ when both partners benefit from the relationship, _________ when one partner benefits and the other is neither harmed nor helped, and ______ when one benefits and the other is harmed in some way as a result of the relationship.
mutualism, commensalism, parasitism
Plant growth is dependent upon __________ which must be continually added to the soil. ________ bacteria that form mutualistic relationships with legumes are involved in this process.
nitrogen, rhizobial
In prokaryotes, there is a nuclear area that contains DNA and resembles the nucleus in eukaryotes; it is referred to as the ________. You Answered
nucleoid
the disease MRSA is caused by
organisms that use horizontal gene transfer, a drug resistant bacterium, a combination of methicillin-and vanomycin resistant bacteria, staphylococcus aureus
In free-living species of bacteria, the outer covering may provide the cell with protection against phagocytosis by _______.
other microorganisms
Animals obtain nitrogen from organic compounds when they eat _______.
other organisms
The bacterial cell wall includes ________, a polymer that consists of two unusual types of sugars linked with short polypeptides.
peptidoglycan
When compared to bacteria, archaea do not have _______ in their cell walls.
peptidoglycan
the cell wall surrounds the ______. the rigid cell wall _________ the cell, maintains the cell's ________, and keeps the cell from ________ hypotonic stress.
plasma membrane, supports, shape, bursting
In addition to their genomic DNA, many bacteria have small amounts of genetic information present as one or more ______, which are circular fragments of DNA.
plasmids
Fimbriae are made of ________ and are shorter than ______________.
protein, flagella or pili
Some bacteria form dormant, durable cells called endospores. However, unlike in fungi and plants, in bacteria the formation of endospores is not a form of ______.
reproduction
Under a microscope, most prokaryotes appear to be similar in _______ and _______ .
size, shape
Bacteria that retain crystal violet stain differ from those that do not retain the stain in having a:
thicker peptidoglycan layer
____________ obtain energy from chemical compounds and ____________ obtain energy from sunlight.
Chemotrophs, phototrophs
True or false: Exchange of genetic material between bacteria sometimes occurs by fusion of gametes
FALSE
Rigid spiral shaped prokaryote is known as a ________, and a flexible spiral-shaped prokaryote is called a __________
Spirillium, spirochete
Most bacterial cells are _______________, or require oxygen for cellular respiration. Some other bacteria, however, are ____________ that use oxygen if it's available, or _____________ that carry out anaerobic respiration.
aerobic, facultative anaerobe, obligate anaerobes
Organisms require nitrogen for the synthesis of _____________ and ____________
amino acids, nucleic acids
Compounds produced by microorganisms that either inhibit the growth of or destroy other microorganisms are called ________.
antibiotics
The two domains of prokaryotes are _______ and ________ .
archaea and bacteria
Organisms that are able to use inorganic compounds as a source of carbon for making organic compounds are called ________.
autotrophs
Rod-shaped prokaryotes are known as ________.
bacilli
Possible shapes for a prokaryotic organism are
bacillus, spirochete, spirillum, coccus, vibrio
Three different types of reproduction in prokaryotes are __________,_________, and __________
binary fission, budding, fragmentation
A high percentage of infections acquired in hospitals involve bacteria inhabiting ________.
biofilms
Many bacteria that inhabit watery environments form dense films called ______ that attach to solid surfaces. _________ that forms in the mouth is one example.
biofilms, dental plaque
________ uses microorganisms to detoxify, the process of removing toxic chemicals, from the environment.
bioremediation
A small, circular piece of DNA that is separate from the main chromosome is:
called a `plasmid
In some bacteria a capsule or slime layer surrounds the ________.
cell wall
Horizontal gene transfer occurs in prokaryotes in at least three ways. Prokaryotic cells take up fragments of foreign DNA or RNA released by other prokaryotes in a process called _______________ . In _________________ , a phage carries bacterial genes from one bacterial cell into another. In the third way, prokaryotes of two different "mating types" may exchange genetic material during ___________
transformation, transformation, conjugation
When genetic material is transferred from parent to offspring, ________ gene transfer occurs. If the organism transfers genetic material to another organism that is not its offspring, _______ gene transfer occurs.
vertical, horizontal
The antibiotic penicillin:
works best on gram-positive bacteria, interferes with peptidoglycan synthesis, works best on gram-negative bacteria