Question 1

Which of these illustrates the correct representation of the binomial scientific name for the African lion?
A)Panthera leo
B)$panthera leo$
C)Panthera $leo$
D)Panthera Leo
E)$Panthera$ $leo$

Accepted Answer

E

Question 2

The common ancestors of birds and mammals were very early (stem)reptiles, which almost certainly possessed 3-chambered hearts (2 atria, 1 ventricle). Birds and mammals, however, are alike in having 4-chambered hearts (2 atria, 2 ventricles). The 4-chambered hearts of birds and mammals are best described as
A)structural homologies.
B)vestiges.
C)homoplasies.
D)the result of shared ancestry.
E)molecular homologies.

Accepted Answer

The 4-chambered hearts of birds and mammals are homoplasies, meaning they are similar traits that evolved independently in different lineages, not due to shared ancestry.

Question 3

In angiosperm plants, flower morphology can be very intricate. If a tree, such as a New Mexico locust, has flowers that share many morphological intricacies with flowers of the sweet pea vine, then the most likely explanation for these floral similarities is the same general explanation for the similarities between the
A)dorsal fins of sharks and of dolphins.
B)reduced eyes of Australian moles and North American moles.
C)scales on moth wings and the scales of fish skin.
D)cranial bones of humans and those of chimpanzees.
E)adaptations for flight in birds and adaptations for flight in bats.

Accepted Answer

The similarities in flower morphology between the New Mexico locust and the sweet pea vine are likely due to shared ancestry, similar to the cranial bones of humans and chimpanzees, which are homologous structures resulting from common descent.

Question 4

Which mutation should least require realignment of homologous regions of a gene that is common to several related species?
A)3-base insertion
B)1-base substitution
C)4-base insertion
D)1-base deletion
E)3-base deletion

Accepted Answer

A one-base substitution may cause a change in the amino acid sequence, but it would not cause a shift in the reading frame or require realignment of homologous regions. Insertions and deletions would cause a frameshift, which would require realignment of the homologous regions. The larger the insertion or deletion, the more challenging it would be to realign the homologous regions.

Question 5

The term "homoplasy" is most applicable to which of these features?
A)the legless condition found in various types of extant lizards
B)the 5-digit condition of human hands and bat wings
C)the beta-hemoglobin genes of mice and of humans
D)the fur that covers Australian moles and North American moles
E)the basic skeletal features of dog forelimbs and cat forelimbs

Accepted Answer

Homoplasy refers to the presence of similar characteristics in unrelated organisms due to convergent evolution. The legless condition found in various types of extant lizards is an example of homoplasy because these organisms have independently evolved this characteristic despite not being closely related.

Question 6

If organisms A, B, and C belong to the same class but to different orders and if organisms D, E, and F belong to the same order but to different families, which of the following pairs of organisms would be expected to show the greatest degree of structural homology?
A)A and B
B)A and C
C)B and D
D)C and F
E)D and F

Accepted Answer

Organisms D and F are in the same order and thus would be expected to have a higher degree of structural homology than organisms in different orders. Therefore, choice E, which pairs organisms D and F, would be expected to show the greatest degree of structural homology.

Question 7

The importance of computers and of computer software to modern cladistics is most closely linked to advances in
A)light microscopy.
B)radiometric dating.
C)fossil discovery techniques.
D)Linnaean classification.
E)molecular genetics.

Accepted Answer

The use of computers and software has revolutionized cladistics by enabling researchers to analyze vast amounts of molecular genetic data. This has led to a more accurate and detailed understanding of the evolutionary relationships among species than was previously possible with traditional methods such as Linnaean classification, fossil discovery, light microscopy, and radiometric dating.

Question 8

Generally, within a lineage, the largest number of shared derived characters should be found among two organisms that are members of the same
A)kingdom.
B)class.
C)domain.
D)family.
E)order.

Accepted Answer

The more closely related two organisms are, the more shared derived characters they should have, and family is a more specific taxonomic level than kingdom, class, domain, and order, making it the best choice for this question.

Question 9

The legless condition that is observed in several groups of extant reptiles is the result of
A)their common ancestor having been legless.
B)a shared adaptation to an arboreal (living in trees)lifestyle.
C)several instances of the legless condition arising independently of each other.
D)individual lizards adapting to a fossorial (living in burrows)lifestyle during their lifetimes.

Accepted Answer

The legless condition has arisen independently in several groups of extant reptiles, indicating that it is not the result of a common ancestor having been legless or a shared adaptation to living in trees. There is no evidence that individual lizards can adapt to a legless condition during their lifetimes.

Question 10

Some molecular data place the giant panda in the bear family (Ursidae)but place the lesser panda in the raccoon family (Procyonidae). Consequently, the morphological similarities of these two species are probably due to
A)inheritance of acquired characteristics.
B)sexual selection.
C)inheritance of shared derived characters.
D)possession of analogous structures.
E)possession of shared primitive characters.

Accepted Answer

The morphological similarities between the giant panda and the lesser panda, despite their placement in different families based on molecular data, suggest that these similarities are due to analogous structures. Analogous structures arise from convergent evolution, where unrelated species develop similar traits independently, often due to similar environmental pressures or ecological roles, rather than from a common ancestor.

Question 11

The scientific discipline concerned with naming organisms is called
A)taxonomy.
B)cladistics.
C)binomial nomenclature.
D)systematics.
E)phylocode

Accepted Answer

Taxonomy is the scientific discipline concerned with naming and classifying organisms. It involves identifying, describing, naming, and classifying organisms based on their characteristics and evolutionary relationships. Cladistics is a method of classification within taxonomy, binomial nomenclature is the system used for naming organisms, systematics is the study of evolutionary relationships among organisms, and phylocode is a proposed set of rules for naming clades based on their evolutionary relationships. Therefore, A is the best choice for the given question.

Question 12

Which of the following pairs are the best examples of homologous structures?
A)bat wing and human hand
B)owl wing and hornet wing
C)porcupine quill and cactus spine
D)bat forelimb and bird wing
E)Australian mole and North American mole

Accepted Answer

The answer of Which of the following pairs are the...

Question 13

Darwin analogized the effects of evolution as the above-ground portion of a many-branched tree, with extant species being the tips of the twigs. The common ancestor of two species is most analogous to which anatomical tree part?
A)a single twig that gets longer with time
B)a node where two twigs diverge
C)a twig that branches with time
D)the trunk
E)neighboring twigs attached to the same stem

Accepted Answer

The common ancestor of two species can be thought of as a point in the evolutionary tree where two twigs diverge. Just like a node in a tree, it represents a point of common ancestry from which two branches (or species) have developed over time.

Question 14

The best classification system is that which most closely
A)unites organisms that possess similar morphologies.
B)conforms to traditional, Linnaean taxonomic practices.
C)reflects evolutionary history.
D)corroborates the classification scheme in use at the time of Charles Darwin.
E)reflects the basic separation of prokaryotes from eukaryotes.

Accepted Answer

The best classification system is one that reflects evolutionary history because it reflects the most accurate understanding of the relationships between organisms. This system takes into account genetic and ecological data in addition to morphology and provides a more scientifically sound basis for classification.

Question 15

The correct sequence, from the most to the least comprehensive, of the taxonomic levels listed here is
A)family, phylum, class, kingdom, order, species, and genus.
B)kingdom, phylum, class, order, family, genus, and species.
C)kingdom, phylum, order, class, family, genus, and species.
D)phylum, kingdom, order, class, species, family, and genus.
E)phylum, family, class, order, kingdom, genus, and species.

Accepted Answer

The correct sequence of taxonomic levels is Kingdom, Phylum, Class, Order, Family, Genus, and Species. This is commonly remembered by the mnemonic "King Phillip Came Over For Good Soup." Option B follows this sequence correctly.

Question 16

Dozens of potato varieties exist, differing from each other in potato-tuber size, skin color, flesh color, and shape. One might construct a classification of potatoes based on these morphological traits. Which of these criticisms of such a classification scheme is most likely to come from an adherent of the phylocode method of classification?
A)Flesh color, rather than skin color, is a valid trait to use for classification because it is less susceptible to change with the age of the tuber.
B)Flower color is a better classification criterion, because below-ground tubers can be influenced by minerals in the soil as much as by their genes.
C)A more useful classification would codify potatoes based on the texture and flavor of their flesh, because this is what humans are concerned with.
D)The most accurate phylogenetic code is that of Linnaeus. Classify potatoes based on Linnaean principles; not according to their color.
E)The only biologically valid classification of potato varieties is one that accurately reflects their genetic and evolutionary relatedness.

Accepted Answer

The phylocode method of classification is based on evolutionary relatedness and genetic relationships, so an adherent of this method would likely argue that the only biologically valid way to classify potato varieties is based on their genetic and evolutionary relatedness, rather than solely on morphological traits like skin color, flesh color, or shape.

Question 17

The common housefly belongs to all of the following taxa. Assuming you had access to textbooks or other scientific literature, knowing which of the following should provide you with the most specific information about the common housefly?
A)order Diptera
B)family Muscidae
C)genus Musca
D)class Hexapoda
E)phylum Arthropoda

Accepted Answer

The genus Musca is the most specific taxon among the given options and provides the most detailed information about the common housefly. It includes all the species of houseflies, and any literature or textbooks specific to Musca would be the most relevant in studying the common housefly.

Question 18

A phylogenetic tree that is "rooted" is one
A)that extends back to the origin of life on Earth.
B)at whose base is located the common ancestor of all taxa depicted on that tree.
C)that illustrates the rampant gene swapping that occurred early in life's history.
D)that indicates our uncertainty about the evolutionary relationships of the taxa depicted on the tree.
E)with very few branch points.

Accepted Answer

A rooted phylogenetic tree is one in which the base represents the common ancestor of all the taxa depicted on the tree. This provides a framework for understanding the evolutionary relationships among the different taxa. Option A is incorrect because a rooted tree doesn't necessarily extend back to the origin of life on Earth. Option C is incorrect because a rooted tree doesn't necessarily illustrate gene swapping. Option D is incorrect because a rooted tree provides a clear picture of the evolutionary relationships of the taxa depicted on the tree. Option E is incorrect because a rooted tree can have multiple branch points, as it shows the relationships between different species.

Question 19

If, someday, an archaean cell is discovered whose SSU-rRNA sequence is more similar to that of humans than the sequence of mouse SSU-rRNA is to that of humans, the best explanation for this apparent discrepancy would be
A)homology.
B)homoplasy.
C)common ancestry.
D)retro-evolution by humans.
E)co-evolution of humans and that archaean.

Accepted Answer

Homoplasy refers to a situation where a trait or sequence similarity arises independently in different lineages, not due to common ancestry, which could explain the similarity between the archaean and human SSU-rRNA sequences.

Question 20

The various taxonomic levels (viz, genera, classes, etc.)of the hierarchical classification system differ from each other on the basis of
A)how widely the organisms assigned to each are distributed throughout the environment.
B)the body sizes of the organisms assigned to each.
C)their inclusiveness.
D)the relative genome sizes of the organisms assigned to each.
E)morphological characters that are applicable to all organisms.

Accepted Answer

The taxonomic levels differ from each other on the basis of their inclusiveness, i.e., how many organisms are included in each level. For example, a class includes multiple orders, while an order includes multiple families, and so on. The other options (A, B, D, and E) are not accurate descriptions of the basis for differences between taxonomic levels.

Quiz 26: Phylogeny and the Tree of Life

Which of these illustrates the correct representation of the binomial scientific name for the African lion?

Which mutation should least require realignment of homologous regions of a gene that is common to several related species?

The term "homoplasy" is most applicable to which of these features?

If organisms A, B, and C belong to the same class but to different orders and if organisms D, E, and F belong to the same order but to different families, which of the following pairs of organisms would be expected to show the greatest degree of structural homology?

The importance of computers and of computer software to modern cladistics is most closely linked to advances in

Generally, within a lineage, the largest number of shared derived characters should be found among two organisms that are members of the same

The legless condition that is observed in several groups of extant reptiles is the result of

Some molecular data place the giant panda in the bear family (Ursidae) but place the lesser panda in the raccoon family (Procyonidae) . Consequently, the morphological similarities of these two species are probably due to

The scientific discipline concerned with naming organisms is called

Which of the following pairs are the best examples of homologous structures?

Darwin analogized the effects of evolution as the above-ground portion of a many-branched tree, with extant species being the tips of the twigs. The common ancestor of two species is most analogous to which anatomical tree part?

The best classification system is that which most closely

The correct sequence, from the most to the least comprehensive, of the taxonomic levels listed here is

The common housefly belongs to all of the following taxa. Assuming you had access to textbooks or other scientific literature, knowing which of the following should provide you with the most specific information about the common housefly?

A phylogenetic tree that is "rooted" is one

If, someday, an archaean cell is discovered whose SSU-rRNA sequence is more similar to that of humans than the sequence of mouse SSU-rRNA is to that of humans, the best explanation for this apparent discrepancy would be

The various taxonomic levels (viz, genera, classes, etc.) of the hierarchical classification system differ from each other on the basis of