Viruses are considered nonliving because
a. they do not locomote.
b. they cannot reproduce independently.
c. their nucleic acid does not code for protein.
d. they are single-celled.
Which of these are found in all viruses?
a. envelope, nucleic acid, capsid
b. DNA, RNA, and proteins
c. capsid and a nucleic acid
d. proteins, nucleic acids, carbohydrates, and lipids
e. tail fibers, spikes, and rod shape
The envelope of an animal virus is derived from the __________ of its host cell.
a. cell wall
What is the correct order of the stages in the lytic cycle of viral reproduction?
a. penetration, attachment, uncoating, biosynthesis, release
b. attachment, release, penetration, biosynthesis, maturation, lysogeny
c. attachment, penetration, biosynthesis, maturation, release
d. maturation, release, attachment, penetration, biosynthesis
Which is not true of prokaryotes?
a. They are living cells.
b. They lack a nucleus.
c. They all are parasitic.
d. They are both archaea and bacteria.
e. They evolved early in the history of life.
Which of these is most apt to be a prokaryotic cell wall function?
Prokaryotes reproduce by means of
a. the lytic cycle.
b. binary fission.
e. the lysogenic cycle.
How do Gram-negative bacteria differ from Gram-positive bacteria?
a. They are not pathogenic.
b. Their peptidoglycan cell wall is thinner.
c. Gram-negative bacteria cannot be Gram stained.
d. They possess a single plasma membrane.
e. Gram-negative bacteria do not photosynthesize.
The cell wall of bacteria is composed of
e. protein capsomers.
a. require a constant supply of oxygen.
b. are killed in an oxygenated environment.
c. do not always need oxygen.
d. are photosynthetic but do not give off oxygen.
a. are chemosynthetic.
b. use the rays of the sun to acquire energy.
c. oxidize inorganic compounds to acquire energy.
d. are always bacteria, not archaea.
A prokaryote that gains organic molecules from other living organisms is a
Gram-negative bacteria that first introduced oxygen into the atmosphere through photosynthesis are
Archaea are distinct from bacteria because
a. some archaea form methane.
b. each have different rRNA sequences.
c. archaea do not have peptidoglycan cell walls.
d. archaea are more closely related to eukaryotes.
e. All of these are correct.
Which of these archaea would live at a deep-sea vent?
d. parasitic forms