What evolutionary question is better addressed by the fig-shaped evolutionary tree in Figure 20.17, as opposed to the more typical, single-trunk phylogenetic tree in Figure 20.2?
- What was the single organism from which all other forms of life on Earth arose?
- Did animals evolve from fungi?
- In which species of eukaryote did chloroplasts first appear?
- Were chloroplasts and mitochondria transferred to eukaryotic cells through horizontal gene transfer?
The phylogenetic tree shows the relationship between plants.
What is the closest relative of hornworts?
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Liverworts.
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Mosses.
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Protracheophytes.
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Charophytes.
The phylogenetic tree shows the relationship between plants.
What is a trait shared with the common ancestor of charophytes (a group of algae) and liverworts (a group of non-vascular plants)?
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The common ancestor has colonized the land.
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The common ancestor could synthesize phenylpropanoids (a group of important organic molecules).
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The common ancestor could synthesize lignin (the major component of bark).
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The common ancestor could synthesize sporopollenin (the tough outer covering of plant spores).
The tree above shows the phylogenetic relationships between four species. A scientist wishes to perform a genetic analysis on all four species in which she determines the number of genetic similarities between all four species. What would she most likely find regarding the genetic similarities between species A, B, D and E?
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Species D and E would share more genetic similarities with each other than with species A and B, and vice versa.
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Species A and E would share more genetic similarities with each other than with species B and D, and vice versa.
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Species D and A would share more genetic similarities with each other than with species A and B, and vice versa.
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Species D and B would share more genetic similarities with each other than with species A and E.
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The scientists spend more time creating the phylogenetic table.
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Scientists find the shortest tree with the smallest number of changes.
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A complex, detailed phylogenetic tree diagram is created.
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The scientists spend more time researching the data for evolutionary connections.
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Analogous-Dolphins are mammals and fish are not, thus their evolutionary paths are quite separate. They have similar body shapes because of their similar environments.
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Analogous-Dolphins and fish are both vertebrates, thus they share an evolutionary history, causing them to have similar body shapes.
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Homologous-Dolphins and fish are both vertebrates, thus they have a similar recent evolutionary history, causing them to have similar body shapes.
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Homologous-Dolphins are mammals and fish are not, thus their evolutionary paths are quite separate. They have similar body shapes because of their similar environments.
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Morphologic and molecular information often disagree.
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Scientists are struggling with molecular systematics.
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Information is not reliable because organisms appear to be closely related when they are not.
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Computer programs help determine relatedness using DNA sequencing, and morphologic and molecular information is more effective in determining phylogeny.
The phylogenetic tree compares the DNA of some bacteria with the DNA found in mitochondria and chloroplasts.
Based on this information, make a hypothesis about how early eukaryote cells obtained chloroplasts and mitochondria.<,/p>
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Early eukaryotes cells evolved mitochondria and got chloroplasts through endosymbiosis.
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Early eukaryotes cells evolved chloroplasts and got mitochondria through endosymbiosis.
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Early eukaryotes cells obtained mitochondria and chloroplasts from two separate endoysmbiosis events.
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Early eukaryotes cells obtained mitochondria and chloroplasts from a single endosymbiosis event.
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This is an example of an early shared ancestor.
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This is an example of convergent evolution.
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This is an example of random DNA homology.
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This is an example of divergent evolution.
The phylogenetic tree compares the DNA of some bacteria with the DNA found in mitochondria and chloroplasts.
What is a conclusion we can reach from this information?
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Mitochondria and chloroplasts are closly related to each other.
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Mitochondria and chloroplasts have a common ancestor, which was a gram negative bacteria.
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Chloroplasts are closely related to chlamdyia.
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Mitochondria are closely related to multiple gram positive bacteria.
The phylogenetic tree compares the DNA found in plant chloroplasts with the DNA of cyanobacteria. The synechocystis at the bottom two rows are the cyanobacteria. The rest of the tree is various plant chloroplasts.
What is a conclusion you can reach based on this data?
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Plants and bacteria evolved analogous, but genetically different photosynthesis mechanisms at the same time.
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Plants and bacteria evolved the same photoysnthesis mechanisms at the same time.
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Plants got their photosynthesis mechanism through endosymbiosis of bacteria. This happened very early in plant evolution.
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Plants got their photosynthesis mechanism through endosymbiosis of bacteria. This happened late in plant evolution.
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directional selection
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stabilizing selection
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disruptive selection
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diversifying selection
Five new species of bacteria were discovered in Antarctic ice core samples. The nucleotide (base sequences of rRNA subunits were determined for the new species. The table below shows the number of nucleotide differences between the species.
Species | 1 | 2 | 3 | 4 | 5 |
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1 | - | 3 | 19 | 18 | 27 |
2 | - | 19 | 18 | 26 | |
3 | - | 1 | 27 | ||
4 | - | 27 |
Which of the following phylogenetic trees is most consistent with the data?
Draw the phylogenetic tree for the species below. Identify where on the tree each feature evolved.
- The ostrich branched off first, followed by the snake, then the frog, then the shark and then the lancelet.
- The shark branched off first, followed by the lancelet, then the frog, then the ostrich and then the snake.
- The lancelet branched off first, followed by the shark, then the frog, then the snake and then the ostrich.
- The lancelet branched off first, followed by the shark, then the ostrich, then the snake and then the frog.
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segments of RNA
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Plasmids
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segments of DNA
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proteins
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the proposal that eukaryotes developed a nucleus first, and then their mitochondrion
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the transmission of genetic material from one species to another through mechanisms other than from parent to offspring
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the fusion of two prokaryotic genomes
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the division of kingdom in the taxonomic classification
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web of life
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meiosis
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gene fusion
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horizontal gene transfer
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gene transfer agents
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horizontal gene transfer
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vertical gene transfer
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basal taxon