Biology - Ch. 12
domain
the highest level category in the classification system and that includes all taxonomic classifications below it; it is the most inclusive taxon
molecular systematics
the methods of using molecular evidence to identify phylogenetic relationships
species
the most specific category of classification
taxonomy
the science of classifying organisms
systematics
the science of determining the evolutionary relationships of organisms
If a new organism were discovered, which of the following would most likely be used to classify it into the appropriate kingdom?
the structure of the organisms anatomy
binomial nomenclature
a system of two-part scientific names for an organism, which includes genus and species names
what best describes a branch point in a phylogenetic tree?
new lineage
monophyletic group
(also, clade) organisms that share a single ancestor
Consider Mendel s pea plants in which a single gene determines whether the peas are yellow from the dominant allele Y or green from the recessive allele y (when both alleles are y). According to the Hardy-Weinberg Principle of Equilibrium, what is the frequency of heterozygous individuals in a population under low selective pressure?
2pq
Who is the Father of classification system?
Carolus Linneaus
Which one of the following sequences shows the correct hierarchy of classification, going from the most inclusive to the least inclusive?
Domain, kingdom, phylum, class, order, family, genus, species
Which group of organisms consist of more than one cell?
Eukarya
Throughout the world, official species names are in
Latin
A scientist finds what she thinks is a new species of rodent on a small Pacific island. However, some similar-looking rodents inhabit some nearby islands. She mates the new rodent with the nearby rodents and gets viable but infertile offspring. Why?
The new rodents probably derive from fairly recent ancestors that experienced dispersive allopatric speciation.
taxon
a single level in the taxonomic classification system
A team of scientists is trying to categorize a new life form they believe is an insect. On what criteria will the scientists base their decision on whether or not to classify the creature as an insect?
The team will study insects in the phylogenetic tree and see whether their new creature matches the characteristics of one of the tree's branches.
For variation to be a meaningful contribution to evolution, what must be true?
The traits that vary in ways meaningful to evolution have genetic components.
Why do scientists classify living organisms?
To study their evolutionary relationship on the basis of shared characteristics
T/F: chimpanzees and humans evolved from a common ancestor?
True; not the same species and not each other
analogous structure
a character found in two taxa that looks similar because of convergent evolution, not because of descent from a common ancestor
shared ancestral character
a character on a phylogenetic branch that is shared by a particular clade
shared derived character
a character on a phylogenetic tree that is shared by a certain clade of organisms
a monophyletic group is what?
a clade
A related group of genera comprise
a family
what is a clade?
a group of organisms that share a common ancestor
clade
a group of taxa with the same set of shared derived characters, including an ancestral species and all its descendants
cladistics
a method used to organize homologous traits to describes phylogenies using common descendent as the primary criterion used to classify organisms
branch point
a point of a phylogenetic tree where a single lineage splits to distinct new ones
A heritable trait that confers on an individual a survival and reproduction advantage in its current environment is called what?
an adaptation
what is derived by a response to similar environmental pressures?
analogies
the wings of a bird and the wings of a bat are examples of what?
analogous structures
maximum parsimony
applying the simplest, most obvious way with the least number of steps
A scientist finds a new organism that may be either a bird or a bat, but it is not clear which group it belongs to. He is pretty sure that the organism has analogous structures with bats and homologous structures with birds, as suggested by genomic data. The organism has one trait that is shared with bats but not birds. Which group should he choose for the new organism and why?
birds because of the homologous structures; the trait shared only with bats is derived
Which of the following parts of a plant cell has a function that is most similar to the function of an animal skeleton?
cell wall
Cladistic taxonomy places the birds as Archosaurs, along with the
crocodilians
rooted
describing a phylogenetic tree with a single ancestral lineage to which all organisms represented in the diagram relate
What is a phylogenetic tree?
diagram that shows evolutionary relationships among groups of organisms
phylogenetic tree
diagram used to reflect the evolutionary relationships between organisms or groups of organisms
Which classification of life contains the highest number of species?
domain
what is phylogeny a description of?
evolutionary history
phylogeny
evolutionary history and relationship of an organism or group of organisms
Evidence believed to support the theory of evolution fall into which major categories?
fossil record, homologous structures, biogeography, and molecular biology
Organisms that are more closely related overlap more how?
genetically and morphologically
Mendel discovered that whether his peas were yellow or green is determined by a single gene in which yellow (Y) is dominant over green (y). Assuming low selective pressure, what does the Hardy-Weinberg Equilibrium frequency term 2pq represent in the peas?
heterozygous, Yy
Characteristics that have arisen as a result of common evolutionary descent are said to be
homologous
Endosymbiont theory is well-accepted for one evolutionary process but controversial for explaining another. What are these two processes, respectively?
horizontal gene transfer via gene fusion and eukaryotic nucleus development
First step of taxonomy is
identification
Which of the following best describes evolution?
it is the change in the frequency of alleles in a population over time
Which list is correct in descending classification (from largest to smallest grouping)?
kingdom, order, family, species
The primary pressure on species to change over time is what?
natural selection
Unicellular eukaryotes are grouped into
only protists
In order from largest to smallest classification, which list is correct?
order, family, genus, species
what do scientists in the field of systematics accomplish?
organize and classify organisms
The timeline of the evolution of different species from a common ancestor, often drawn as a tree-like diagram, is known as a ___________ tree
phylogenic
Modern classification is based on
phylogeny
In general, which two characteristics of an organism are used to classify it?
physical features and genome
Which of the following groups of organisms uses sunlight to convert carbon dioxide and water into sugar and oxygen?
producers
what kind of trait is similar to cladistics?
shared derived traits
When writing species epithets, it is sometimes permissible to abbreviate the _______ name
sometimes permissible to abbreviate the genus name
The group of similar plants which breed freely among themselves constitute a
species
what is the most specific category of the taxonomic classification system?
species
Two organisms mate and have offspring. How could you test to see if the parents were the same species?
test to see if offspring are fertile
order
the category in the taxonomic classification system that falls within class and includes families
genus
the category in the taxonomic classification system that falls within family and includes species; the first part of the scientific name
phylum
the category in the taxonomic classification system that falls within kingdom and includes classes
family
the category in the taxonomic classification system that falls within order and includes genera
class
the category in the taxonomic classification system that falls within phylum and includes orders
kingdom
the category in the taxonomic classification system that falls within the domain and includes phyla
Viruses are denied a kingdom of their own because
they are not organisms
what is true about organisms that are a part of the same clade?
they evolved from a shared ancestor
Two populations of crickets have stopped interbreeding over time, although they reside in the same geographic region. What is one possible explanation?
they have developed a temporal isolation, a kind of prezygotic barrier
sister taxa
two lineages that diverged from the same branch point
Individual differences with a genetic basis lead to ______ in successive generations.
variation