Which of the following is used by biologists around the world to name living organisms at the species level?
Cladistics
Phylogenetics
The binomial system
The three domain system
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Syllabus Edition
First teaching 2014
Last exams 2024
Which of the following is used by biologists around the world to name living organisms at the species level?
Cladistics
Phylogenetics
The binomial system
The three domain system
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The onion plant, Allium cepa, and wild garlic, Allium ursinum, are flowering plants. Which of the following statements about onions and wild garlic are correct?
Onions and wild garlic are in the same class and the same genus.
Onions and wild garlic are in the same class and a different genus.
Onions are in the order cepa and wild garlic is in the order ursinum.
Onions and wild garlic both belong to the Allium family
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Thysanozoon nigropapillosum, Rhizostoma pulmo, and Deroceras agreste are species of animal. T. nigropapillosum has bilateral symmetry and a single opening for mouth and anus. R. pulmo has radial symmetry, and D. agreste has bilateral symmetry and a single muscular foot. Which phyla in the table are correct for T. nigropapillosum, R. pulmo, and D. agreste?
 | T. nigropapillosum | R. pulmo | D. agreste |
A. | Mollusca | Porifera | Arthropoda |
B. | Annelida | Cnidaria | Platyhelminthes |
C. | Platyhelminthes | Cnidaria | Mollusca |
D. | Platyhelminthes | Porifera | Mollusca |
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The diagram shows a cladogram for part of the order artiodactyla.
* denotes a now extinct group.
To which group in the cladogram are the Cetacea most closely related?
Hippopotamidae
Raoellidae
Ruminantia
Mesonychia
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Theories can change when new evidence emerges. Evidence relating to the evolutionary relationships between organisms can lead to their reclassification. What led to the reclassification of the figwort plant family?
Observations about flower shape.
The figwort family was too large.
The figwort family formed a clade.
Analysis of chloroplast DNA
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Which of the following is not an important reason for the binomial system of naming organisms?
Scientists need to be able to communicate clearly with each other about their work.
The common names of many species are outdated and should no longer be used.
Different countries may use the same common name for different species.
Woodlice are known by more than 50 different common names.
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Which of the following are reasons for the development of the three domain system of classification?
I and II only
II only
II and III only
I, II, and III
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Which of the following species are most closely related?
I and II
I and III
I and IV
II and IV
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Which of the following apply to natural classification?
Â
A |
Members of a natural group are descended from a common ancestor |
Members of a natural group always have similar characteristics |
Natural classification can be easily carried out using observation alone |
B |
Members of a natural group must have a recent common ancestor |
Members of a natural group are likely to have similar characteristics |
Natural classification is made easier by DNA sequencing technology |
C |
Members of a natural group are descended from a common ancestor |
Members of a natural group are likely to have similar characteristics |
Natural classification is made easier by DNA sequencing technology |
D |
Members of a natural group must have a recent common ancestor |
Members of a natural group always have similar characteristics |
Natural classification is made easier by DNA sequencing technology |
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To which plant phylum does the plant in the diagram belong, and why?
Â
 |
Phylum | Reason |
A |
Coniferophytes | Reproduction takes place via pollen and ovules located in cones |
B |
Filicinophytes | Leaves are divided structures known as fronds |
C |
Angiospermophytes | Roots, stems, and leaves are present |
D |
Angiospermophytes | Reproduction takes place via pollen and ovules located in flowers |
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Which of the following animals can be classified in the phylum annelida?
Arenicola marina, a worm with a cylindrical body that has bristles along its sides.
Bipalium kewense, an unsegmented worm with a distinctive hammer-shaped ‘head’ and mouth/anus located in the middle of its body.
Boettgerilla pallens, also known as the worm slug, has a long, narrow body, and a yellow-grey coloured muscular foot. It can dig burrows to a depth of up to 60cm.
Schistosoma haematobium, a parasitic fluke. The body of males is leaf-like in shape, and can roll up to gain a cylindrical appearance. Humans are the primary host.
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Which of the following is not a feature of a clade?Â
All members of a clade descend from a common ancestor.
Clades are formed on the basis of evolutionary relationships.
Clades are usually identified by observing homologous characteristics.
Clades must include all the descendents of a common ancestor, living and extinct.
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The data below shows the number of DNA base sequence matches found between four species of marine mammal when a short section of their DNA is sequenced.
Â
 |
Humpback whale | Sperm whale | Harbour porpoise | Bottlenose dolphin |
Humpback whale |
 |
 |
 |
 |
Sperm whale | 62 |
 |
 |
 |
Harbour porpoise | 59 | 59 |
 |
 |
Bottlenose dolphin | 56 | 53 | 62 |
 |
Â
What can be concluded from the data?
Sperm whales are more closely related to humpback whales than they are to harbour porpoises or bottlenose dolphins.
Harbour porpoises are more closely related to humpback whales than they are to sperm whales.
All four species are more closely related to each other than they are to other marine mammals.
All four species together form a clade.
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Dichotomous keys can be used to identify species from their observable features.
To which order of insects does the insect below belong? Note that the insect is shown at rest and not in flight.
1 |
Hard wing cases are present. . . . . . . . . . Hard wing cases are not present. . . . . . . . . . |
Coleoptera Go to 2 |
2 |
Wings are not membranous (not thin and translucent). . . . . Wings are membranous (thin and translucent). . . . . |
Go to 3 Go to 4Â |
3 |
Wings are leathery. . . . . . Wings are scaly. . . . . . |
Orthoptera Lepidoptera |
4 |
Only one pair of wings used to fly (the second pair is very small). . Two equal-sized pairs of wings are used to fly. . . . . . |
Diptera Go to 5 |
5 |
Wings held out at right-angle to body when resting. . . . . Wings are folded over the body when resting. . . . . |
Odonata Hemiptera |
Lepidoptera
Odonata
Coleoptera
Hemiptera
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Which of the following cannot be concluded from the cladogram below?
Chimps and bonobos are more closely related to each other than to any other species of primate.
Chimps, bonobos, humans, and gorillas form a clade.
Lemurs diverged from the rest of the primates around 56 million years ago.
Chimps, bonobos, humans, and orangutans form a clade.
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RNA analysis led to the development of the three domains system of classifying organisms. More recent methods of building evolutionary trees has led to the proposal of the two domains system. The image compares the three domains tree and the two domains tree.
Which of the following pairs of statements correctly compares the three domains and two domains trees?
 | Three domains | Two domains |
A. | The eubacteria form a clade | The eubacteria form a clade |
B. | The eukaryotes share a common ancestor with the archaea | The common ancestor of all the eukaryotes is within the archaea |
C. | The archaea form a clade | The archaea form a clade |
D. | The eukaryotes are more closely related to the euryarchaeota than to any other group | The eukaryotes are more closely related to the lokiarchaeota than to any other group |
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The graph shows the rate at which amino acids are substituted in three different types of protein; some amino acids can be substituted multiple times over a long period of time. Note that land plants are thought to have evolved around 500 million years ago, insects are thought to have evolved around 400 million years ago, and mammals around 170 million years ago.
Which of the statements about amino acid substitution are correct?
I. Amino acids in cytochrome C proteins are substituted at a rate of 5 per 100 million years.
II. All proteins are equally useful for determining the length of time since species diverged from each other.
III. Cytochrome C proteins are likely to be involved in a chemical process that is highly conserved across all living organisms.
IV. Analysis of amino acid sequences in fibrinopeptide proteins can be used to classify arthropoda.
I, II, and III only.
I and III only.
II and III only.
II, II, and IV only.
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The photograph shows a succulent cactus plant (left) of the family cactacae and a succulent euphorbia plant (right) of the family euphorbiaceae. The diagram below shows a representation of a cladogram that includes both plant types. The horizontal lines crossing the branches of the cladogram indicate the evolution of some plant characteristics.
Cactus image courtesy of Nabin K Sapkota licensed under the Creative Commons Attribution-Share Alike 4.0 International license, and adapted and redistributed under conditions found at https://creativecommons.org/licenses/by-sa/4.0/deed.en and euphorbia image courtesy of Bernard Dupont licensed under the Creative Commons Attribute-Share Alike 1.0 Generic license, and adapted and redistributed under conditions found at https://creativecommons.org/licenses/by-sa/2.0/
Which statement correctly explains the appearance of succulent cacti and euphorbias?
The features of cacti and euphorbias are homologous as they have been inherited from a common ancestor.
The features of cacti and euphorbias are homologous as they are structurally similar but have a different role.
The features of cacti and euphorbias are analogous as they are structurally different but have a similar role.
The features of cacti and euphorbias are analogous as they evolved independently of each other from different ancestors.
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The table shows a short section of the DNA base sequence of three different species.
Species | Base sequence |
1 | ATCTGC |
2 | CCTGGT |
3 | ACCTAC |
Which cladogram best represents the relationships between species 1, 2, and 3?
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The table contains a dichotomous key for identifying several animal species.Â
1. |
Body plan has some form of symmetry.......... Body plan has no symmetry.......... |
Go to 2 Suberites carnosus |
2. |
Single gut opening for mouth and anus.......... Separate gut openings for mouth and anus.......... |
Go to 3 Go to 4 |
3. |
Radial symmetry.......... Bilateral symmetry.......... |
Chrysaora colorata Pseudoceros dimidiatus |
4. |
Closed circulatory system.......... Open circulatory system.......... |
Hermodice carunculata Go to 5 |
5. |
Soft body.......... Body has a hard exoskeleton.......... |
Philomycus carolinianus Melo proscarabaeus |
Which species belongs to the phylum annelida?
Pseudoceros dimidiatus
Hermodice carunculata
Philomycus carolinianus
Suberites carnosus
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