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BIO 1421-Test #!
Which virus attacks white blood cells?
Prokaryotes are helpful to humans because they...
-help plants utilize atmospheric nitrogen.
-can clean up toxic waste
-are used to make various foods.
-sythesize vitamins within our intestinal tracts.
The concept of evolution is based upon
survival and reproductive success of organisms with favorable variations
Measles is caused by
Tetanus is caused by ______ bacteria that are growing in deep puncture wounds
Which is the first explanation of a problem in thinking of scientist?
The oldest fossil organisms presently know have been dated at approximately how many years old?
Bacteria cause which diseases?
A virus basically consists of
RNA or DNA and a protein coat
Evolution is described as change from pre-existing life forms to modern-day organisms. What actually changed?
ability of organisms to cope with external stimuli
A carefully formulated scientific explanation that is based on a large accumulation of observations and is in accord with scientific principles
smallest sized organisms
Prokaryotic cell walls function
to prevent the cell from bursting in a hypotonic (watery) environment
What may cause the disease known as lockjaw?
The earliest (oldest) fossils resemble modern
what is a normal inhabitant of a cow's digestive tract that can cause harm to people when it contaminates ground beef
the method by which bacteria reproduce
The main difference between an autotroph and a heterotroph is
how they obtain energy
Antibiotics can only be effective against a
improperly folded proteins
When a virus takes over the machinery of a cell, it forces the cell to manufacture
more viral particles
Unlike aerobic prokaryotes, anaerobic prokaryotes can obtain energy when _____ is not available.
The slime layer around the bacterial cell
A bacterial colony that forms a grape-like cluster of round cells
Endospores are produced by
Strep throat is caused by Streptococcus, at type of
science is based on
Intestinal gas is evidence of active _____ in one's digestive tract.
Viruses that attack prokaryotes
which environments would you normally find prokaryotes?
-a spoonfull of soil
-an animal's intestinal tact
-a single drop of saltwater
What do the sticky layers of protective slime produced by some bacteria enable them to do?
stick together and form biofilms
Nearly all viral multiplication cycles require _____ steps.
Which represents the highest degree of certainty?
Botulism can cause
paralysis, distruped breathing, and death.
It appears that the pathogen responsible for "mad cow disease" also in human causes
Lyme disease is cause by _____ that are transmitted to humans by ticks.
When nutrients are scarce or stress occurs some bacteria
When a disease spreads fast across countries at the same time this is called a _______?
In a word, evolution means _____.
Herpes is caused by
For which of the following diseases or conditions should antibiotics be used?
Endospores as old as _____ years old have been revived into living bacteria.
Most scientists do not consider viruses to be "alive" because
their metabolic machinery is borrowed from the host cell.
When bacteria divide by fission each daughter cell inherits
The rhyme or verse "Ring around the rosey..." is related to what epdidemic?
any infectious agent that can invade a host organism and multiply on or in it.
Multicellularity allows organisms to
Which is a swamp gas, intestinal gas, and explosive gas in a coal mine (killed miners recently)?
In ancient Rome which of the following words meant " poisonous ", "venemous" or "virulant?"
Flagella in bacteria
are specialized for movement through rotory spin.
Diverse viruses infect organisms of
Mad cow disease, also called variant Creutzfelt-Jakob disease, is caused by
Which of the following is characteristic of HIV?
RNA enclosed in a protein coat
Contagious diseases are spread by
The smallest organizational unit having a capacity to survive and reproduce on its own its
require high salt concentrations
When not dividing, bacteria have ____ chromosome(s) and may have extra circles of_____ called plasmids.
Pairs of rod-shaped bacteria are called
Viroids differ from viruses in that the former lack
tightly folded strands or circles of RNA and poses no protein coat. These bits of "naked" RNA cause many diseases in plants.
viruses include some forms that are able to attack bacteria.
The validity of scientific discoveries cannot be based on
Which of the following allow the bacteria to join together to transfer genes?
In bacteria, DNA is found
as a circular thread
A virus cannot replicate without pirating ______ from a specific host cell.
Rod shaped bacteria are called
is not caused by bacteria
can serve as a source of antibiotics
The oldest living forms of life on Earth are the
Infective proteins are known as
Viruses have a _____ and a ____.
DNA or RNA; protein coat
Which of the following options correctly pairs a structure with its function in prokaryote cells?
pili=help prokaryotes stick to each other and to surfaces