Chapter 25-26
the two types of reproductive cycles observed amounf viruses are ____ and _____
lytic-lysogenic
most viruses have _____ but do nt have
capsids/envelopes
The shape of the viruses is determined by the
capsomers
In 1969 RH Whittaker proposed a 5 kingdom classification based mainly on?
cell structure and how an organism derived nutrition
Phylogenetic tree that uses clades to show evolutionary relationships is called a ______.
cladogram
Phylogenetic systematics produces branching diagrams called:
cladograms
human viruses can enter human cells by fusion with the cells membrane or by:
endocytosis
____________ is the study of diversity and of organisms and their evolutionary relationships.
Systematics
Before the developmental of microscope, organisms were only placed in to a kingdom ______ or __________.
Plantae or Anamalia
The principle_________ is based on the experience that the simplest explanation is probably the correct one.
parsimony
When the organism in a given taxon do not include all the descendants of an ancestoral species __________.
polyphyletic group
which classification level would be the most inclusive
phylum
The specificity of viruses to diffrent types of cells is due to _____ sites on the host cell.
receptor
the DNA polymerase used by retroviruses in transcription is called_________.
reverse transcriptase
Satellites are ____ agents that depend on co infection of host cell with a helper virus
subviral
Some biologists are considered adopting a diffrent classification scheme based on common ancestors called:
Phylocode
according to the _________ hypthesis viruses may have originated as mobile genetic elements such as transposons or plasmids.
cellular orgin
a symptom of a transmissable spongiform encephalopathy is:
degenerative of the brain and central nervous system.
viruses have all the following EXCEPT:
have mitochondria
gene swapping between organisms in one taxon and related organisms in another taxon is called ______________________.
horizontal gene transfer
Viruses:
cannot ind. perform metabolic activities
homoplastic structures are a result of ______ evolution.
convergent
virulent phages
destroy bacteria
IN Linnaeus taxanomy is closley related species are assigned to the same genus, and closley related genera are grouped into
families
Phages are being considered for:
antibiotics in bacterial infections
a cladogram is based on:
homologous characteristics
_____ conversion occurs when a bacterium carrying viral genes takes on new atypical characteristics.
lysogenic
an example of homologous structures is the wing of a bat and:
the arm of a human
a taxon that includes all the descendents of an ancestor is called:
monophyletic
When organisms in a given taxon include the ancestoral species and all of its descendants, the group is said to be _____________.
monophyletic group
Viruses can be classified based on the type of organisms they infect or on their
host range
viruses that attack bacteria are called:
phages
the evolutionary history of a group of organisms form a common ancestor is termed
phylogeny
viroids cause a variety of plant diseases and are composed only of:
strands of RNA
the variety of living organisms and ecosystems is referred to as ___________.
Biodiversity
_______ developed the binomial system of nomenclature.
Carolus Linnaeus
a taxon that diverges earlier than the other taxa being considered in acladistic analysis is
an outgroup
Bears and dogs are
chordates,mammals, and carnivores
the bacterium that causes botulism disease is harmless until it:
contains a certain prophage DNA
a ______ character is a trait that has evolved relatively recently.
derived
closley related or similar species are grouped into a single:
genus
Retroviruses differ from other RNA viruses by:
having reverse trans. instead of RNA dependent RNA polymerase
which of the following diseases is not caused by a virus
herpes virus
an _______ is a taxon that is considered to have diverged earlier than the taxa under investigation.
outgroup
when the organisms in a given taxon do not share a common ancestor the group is said to be _____________.
paraphyletic group
viral infecitons in humans spread via the circulatory system. iral infections in plants spread from cell to cell via:
plasmodesmata
shared ancesteral charcters may also be called:
plesiomorphic charcters
Mad cow disease is an example of an infection caused by a:
prion
according to the ______ hypothesis, viruses evolved from small independent cells that were parasites in larger cells.
regressive
the five stages of a lytic infection are attachment, penetration, _______, assembly, and release.
replication
features that occured in a recent common ancestor and remain in the descendants of that organism are called ___________.
shared derived characters
The phenetic system is based primarily on:
the number of shared characteristics
Most biologist recognize ____ domains
3
THe worldwide variety of oranisms and ecosystems is termed:
biodiversity
_____________ describes the independent evolution of similar structures in distantly related organisms.
convergent evolution
temperate viruses:
do not always destroy their hosts
a prophage
is phage DNA that is intergrated into bacterial DNA
TAxanomy is the science of:
naming,describing, and classifying organisms
viruses that cause diseases
pathogens
RNA viruses called _____ transcribe their RNA into a DNA strand.
retroviruses
features that appeared a long time ago and remained in the in the descendants of that organisms are called ___________.
shared ancestor characteristics
The Broadest most inclusive group is called a _____
Domain
scientist using evolutionary systematics to construct a phylogenetic tree would use:
a combination of ancestoral and derived characters
viruses that have only lytic cycle are said to be ______
virulent
The first kingdom to be recognized beyond plantae and anamalia was:
Protista
viroids are hardy and resist heat and ultraviolet radiation because of the condensed folding of their ______.
RNA
_______ is credited with the discovery of prions as a new biological principle of infection
STanley Prusiner
the scientific study of the diversity of organisms and the evolutionary relationships between them is referred to as:
Systematics
viruses are classified by:
an international committee
viruses were first identified:
because they caused an infection and were small enough to pass through filters that trapped bacteria.
the protein coat of a virus is called the:
capsid
according to ____ hypothesis, viruses appeared early in the history of life, even b4 three domains diverged.
coevolution
Viroids are generally found within the host cell ________ and appear to interfere with ________.
nucleus, gene regulation
IN the late 1970's Woes argued that Prokaryotes account for 2 or 3 major branches of organims because:
of diffrences in sequence analysis of 16sRNA of difrent group of prokaryotes
viral proteins can damage host cells by:
overwhelming the host cell with large numbers of viruses
when faced with multiple possible cladograms the criteria of ____ is employed
parsimony
The original two kingdoms that were established to organize living organisms were_________.
plantae and anamalia
Viral DNA that is intergrated into host DNA is called a ______ and bacterial cells carrying intergrated viral DNA are called _______
prophage-lysogenic cells
comparison of ______ has been recently used to support the hypothesis that fungi are most clsley related to animals than to plants.
ribosomal RNA sequences
the genome of most plant viruses consist of _________
single strand RNA
Prions are found in the brains of patients with fatal degenerative brain disease called:
transmissable spongiform encephaiopathies
Genes are transmitted from parents to offspring in a process called _______.
vertical gene transfer
viruses range from size _____ to _____ nm
20-300
The term clade most closley refers to:
a group of organims that share common characteristics inherited from a common ancestor