Ch 19 Flashcards
Which structure helps bacteria to attach within the tissues that they will infect? Flagella Cell wall Capsule Nucleoid
Capsule -
The gelatinous capsule that covers some bacteria helps them attach to the tissues that they will infect
True or false. Bacteria reproduce by an asexual process in which one parent cell gives rise to identical daughter cells.
True-
Bacteria reproduce by binary fission, which is an asexual process in which one parent cell splits in two to give rise to identical daughter cell
The genetic material of HIV consists of \_\_\_\_\_. single-stranded DNA single-stranded RNA double-stranded DNA double-stranded RNA none of the above
single-stranded RNA-
The genetic material of HIV consists of two molecules of single-stranded RNA
What is the function of reverse transcriptase?
It catalyzes the formation of a polypeptide from an RNA template.
It catalyzes the formation of DNA from a polypeptide template.
It catalyzes the formation of RNA from a polypeptide template.
It catalyzes the formation of RNA from a DNA template.
It catalyzes the formation of DNA from an RNA template
It catalyzes the formation of DNA from an RNA template.
What is the source of a viral envelope? host cell DNA prophages provirus host cell membrane viral glycoproteins
host cell membrane-
The viral envelope is derived from host cell membrane.
Double-stranded viral DNA is incorporated into a host cell as a \_\_\_\_\_. promoter provirus transposon lac homeoboxes
provirus-
“Provirus” is the name given to double-stranded viral DNA that has been incorporated into a host cell’s genome.
Peptidoglycan is found in the cell walls of bacteria. fungi. plants. viruses. archaea.
bacteria.
You discover a new "particle." It has only RNA as a nucleic acid and lacks both a membrane and cytoplasm. This "particle" is a(n) archaea. prion. virus. fungus. bacteria
virus
Unlike aerobic prokaryotes, anaerobic prokaryotes can obtain energy when ________ is not available.
oxygen
Cyanobacteria obtain energy through ________.
photosynthesis
Bacterial endospores are used for forming biofilms. bacterial reproduction. bioremediation. keeping the bacteria alive under harsh conditions. attracting viruses.
keeping the bacteria alive under harsh conditions
Dental plaque is an example of bacterial flagella. a cell membrane. an endospore. beneficial bacteria. a biofilm.
a biofilm
A bacterium capable of causing disease in a host is a(n) ________.
pathogen
Through which process are bacteria able to exchange genetic material? Anaerobic respiration Conjugation Endospore formation Sexual reproduction Photosynthesis
Conjugation
In bacteria, the small, circular pieces of DNA that are located outside the chromosome are called sex pili. endospores. flagella. plasmids. bacteriophages.
plasmids.
Mutations that improve the survival and reproduction of organisms, and thus contribute to the evolution of species, arise rapidly in prokaryotes due to their anaerobic metabolism. cell wall composition. absence of a nucleus. rapid rate of cell division. sexual reproduction.
rapid rate of cell division
The use of bacteria to break down pollutants is referred to as nitrogen-fixation. binary fission. bioremediation. biosynthesis. biofixation.
bioremediation.
To limit your risk from foodborne bacteria, you should
eat only uncooked eggs.
cook foods thoroughly.
thaw frozen foods at room temperature.
keep foods at or above room temperature.
avoid refrigerating foods.
cook foods thoroughly.
In which of these environments would you normally find prokaryotes?
An animal’s intestinal tract
A single drop of seawater
Human skin
A spoonful of soil
All of the above - just about everywhere
All of the above - just about everywhere
Antibiotics can be effective only against a prion. bacterium. virus. viroid
bacterium.
All bacteria are harmful to humans. True or False?
False
How does a bacterium survive long periods of desiccation?
Endospores that encase the genetic information, burst, and wait until good conditions to return to bacterial form
How does biofilms help bacteria?
It provides a sticky slime layer that defends against antibiotics and disinfectants but allow bacteria to easily adhere to surfaces.
Through what structure do bacteria exchange genetic information?
plasmid- a small circular DNA molecule separate from bacteria chromosome may carry resistance gene to antibiotics - through the cytoplasm