Bio Final
what are the small circles of DNA that exist within the bacterial cytoplasm in addition to the bacterial chromosome
plasmids
what is a chain of round bacteria called
streptococci
what is vertical gene transfer
the transmission of genetic material from parents to offspring during reproduction
which of the following are RNA viruses that have DNA polymerase
retroviruses
how do retroviruses differ from other RNA viruses
retroviruses have a unique infection technique of their host cells
which has an unusual characteristic in that their circular DNA does not have genes for making the proteins needed to replicate and produce new viruses
viroid
Which characteristic defines a virus?
viruses cannot metabolize
What are sub viral agents that depend on co-infection of a host cell with a helper virus?
Satellites
the most common mode of reproduction in bacteria is:
binary fission
small hairlike structures made up of protein on the surface of bacteria are called
fimbriae
plasmids of bacteria often have genes involved in
antibiotic resistance
the DNA molecule is packaged into thread-like structures called
chromosomes
what is the purpose of sex pili
To transmit DNA between bacteria
humans have ______ pairs of chromosomes
23
What is the protein coat of a virus called?
Capsid
What is the correct unit of measurement for the size of most viruses?
Nanometers
Which statement about viruses is false?
Viruses can manufacture proteins
which statement about bacteria is true
a large percent of bacteria are pathogenic
the bacterium that causes botulism disease is harmless until it:
contains a certain prophage DNA
another name for horizontal gene transfer is
lateral gene transfer
According to the progressive hypothesis, viruses may have originated as mobile genetic elements such as
mRNA
_____________ are those that have been almost eradicated and then suddenly recur, causing an epidemic
re-emerging viruses
when a virus penetrates the host plasma membrane and moves into the cytoplasm it is called:
release
What is the purpose of phage therapy
to target specific bacteria in the body and destroy them
What type of conversion occurs when a bacterium carrying viral genes takes on new, atypical characteristics?
transducing
What is a prophage?
it is phage DNA that is integrated into viral DNA
at what stage of a lytic infection are phage components put together to make new viruses?
assembly
at what stage of the lysogenic cycle would a prophage appear
integration
the genome of most plant viruses consists of what kind of RNA
mRNA
which statement about an F factor is false
It is found in recipient cells, not donor cells.
What are the viruses that attack bacteria?
Phages
how do bacteria move
By means of a rotating flagella
What is commensalism?
a relationship between individuals of two species in which one benefits and the other derives benefit nor harm
prokaryotes divide using a process called
binary fission
Which if the following are responsible for some very serious diseases, including ebola hemorrhagic fever
diarrheal diseases
before an animal cell's membrane fuses with a virus, the virus must first:
duplicate its DNA
Which hypothesis asserts that viruses are remnants of cellular organisms and evolved from small cells that were parasites in larger cells
regressive hypothesis
most bacterial cells can keep from bursting in a hypotonic environment because of:
a rigid cell wall
which of the following are rod-shaped bacteria
bacilli
how do some bacteria respond to adverse environmental conditions
bacteria from endospores
a bacterium that uses the oxidation of inorganic compounds to provide energy for manufacturing nutritious organic compounds is a:
chemoautotroph
which of the following cause disease and often death
diarrheal diseases
which structure acts like a motor for the bacterial flagellum
hook
bacterial conjugation is related to
horizontal gene transer
Which of the following is the most common structure of a virus
icosahedron
viral proteins can damage host cells by which process?
overwhelming the host cell with a large number of viruses
Why is penicillin ineffective against gram-negative bacteria
penicillin cannot reach the thin peptidoglycan layer easily because it is protected by the bacterias outer membrane
Which of the following typically occurs all at once and results in rapid cell lysis?
phage release
peptidoglycan consists of
sugars crosslinked with proteins
although bacteria lack membrane-bound organelles, such as chloroplasts and mitochondria, they can still preform the functions of these organelles by localizing certain metabolic enzymes on:
the plasma membrane
some bacteria avoid being phagocytized by a goat's immune system by means of:
their capsule or slime layer