chapter 28

Question 1

microbiology is the study of microbes. these include all but which of the following?

Answer 1

plants

Question 2

what general feature is necessary to consider an organism a microbe?

Answer 2

small enough that a microscope is required to see them

Question 3

millers’ laboratory experiments showed that

Answer 3

the primitive gases can react together to produce small organic molecules

Question 4

which of the following kinds of molecules is thought to have been absent from the primitive reducing atmosphere?

Answer 4

oxygen (O2)

Question 5

considering the various theories, the energy used in forming organic molecules in the primitive atmosphere could have come from all EXCEPT

Answer 5

sound

Question 6

what is the evolutionary relationship among archaea, bacteria, and eukarya?

Answer 6

archaea and eukarya share nucleic acid similarities, so eukarya split off from archaea

Question 7

a new classification by domains separates prokaryotes into

Answer 7

archaea and bacteria

Question 8

one bacterial cell passes DNA to a second cell through a sex pilus in the process of

Answer 8

conjugation

Question 9

bacterial cells pick up free pieces of DNA from the medium pieces that were released from dead bacteria in a process called

Answer 9

transformation

Question 10

which of these is a correct description of a form of horizontal gene transfer in bacteria?

Answer 10

conjugation occurs when a cell passes DNA to another cell by means of a sex pilus

Question 11

which type of genetic exchange occurs among bacteria in which DNA is carried into a bacteria cell by means of a virus?

Answer 11

transduction

Question 12

which statement is true about bacteria?

Answer 12

they contain a single, circular DNA molecule as the genetic material

Question 13

which statement is NOT true about bacteria?

Answer 13

they reproduce sexually

Question 14

the capsid of a virus is composed of

Answer 14

protein

Question 15

which of the following is NOT true about viruses?

Answer 15

they contain nucleic acid, protein, and mitochondria

Question 16

the innermost core of a virus’ structure is made up of

Answer 16

either DNA or RNA

Question 17

a viral envelope describes

Answer 17

the outer layer of some viruses composed of the host’s plasma membrane

Question 18

which of these is the most accurate description of a virus?

Answer 18

chemical complexes of RNA or DNA protected by protein

Question 19

which of the following is considered to be acellular?

Answer 19

viruses

Question 20

the life cycle stage of an animal virus during which a mature capsid forms around copies of the viral RNA genome is

Answer 20

assembly

Question 21

which stage of viral reproduction takes place when the spikes of the virus bind to a specific receptor molecule on the surface of a host cell?

Answer 21

attachment stage

Question 22

when an enveloped animal virus enters a cell during the entry stage

Answer 22

the protein capsid is removed through uncoating to expose the viral genome

Question 23

bovine spongiform encephalopathy (BSE), or “mad cow disease,” is caused by a

Answer 23

prion

Question 24

some human diseases appear to be due to protein agents that may convert other normal proteins in the cell to also become these agents. this new disease protein agent is called a

Answer 24

prion

Question 25

who invented the term “virus”?

Answer 25

Louis Pasteur

Question 26

cyanobacteria

Answer 26

does photosynthesis similar to green plants

Question 27

the process of bacterial reproduction is referred to as

Answer 27

binary fission

Question 28

the first membranes that formed before full cells were likely made of

Answer 28

fatty acids

Question 29

which type of archaen is likely to be found in the intestines of animals

Answer 29

methanogen

Question 30

Antonie van Leeuwenhoek

Answer 30

improved microscope lenses to allow him to see tiny organisms he called animalcules

Question 31

Louis Pasteur

Answer 31

did experiments to refute the concept of spontaneous generation