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86 Cards in this Set
- Front
- Back
The cumulative change in the heritable characteristics of a population. |
Evolution |
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Many small changes added together to make a big change. |
Cumulative change |
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What are 4 pieces of evidence for evolution? |
The Fossil Record; Selective Breeding; Homologous structures; Continuous variation |
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True or false: older fossils are buried deeper. |
True |
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What is selective breeding? |
Humans select which organisms in a population reproduce, quickly altering the characteristics of that population. Also called artificial selection |
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What are homologous structures? |
Structures among many organisms that have similar structure even though they're for different functions |
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What is an example of a homologous structure? |
Pentadactyl limb |
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What kinds of organisms is the pentadactyl limb used by? And what do they use it for? |
Mammals, birds, amphibians, reptiles; walking, grasping, flying, swimming |
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A spectrum of many different phenotypes, especially among different populations of a species |
Continuous variation |
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True or false: Continuous variation supports the idea that evolution happens very quickly |
False; continuous variation supports the idea that evolution happens gradually. New species arise by a subtle constant rate of change |
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When one species splits into multiple species |
Diverge |
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When one species diverges into many, for example to colonize new food sources |
Adaptive radiation |
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Pigment that makes organisms darker |
Melanin |
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Describe Industrial melanism. |
The soot produced from the Industrial revolution caused the most common phenotype of the peppered moth to change from light to dark (due to the darker ones being able to better blend in with the dark bark on the trees) |
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True or False: Natural selection can only occur if there is variation among members of the same species. |
True |
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What is the mechanism by which evolution happens? |
Natural Selection |
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Nature selection is nature selecting which phenotypes live and _________. |
Reproduce |
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What are the 4 steps of evolution? |
Overproduction of offspring; struggle for survival; Natural Selection; Popular phenotypes arise |
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Give a brief description of the first step of evolution. |
Overproduction of offspring: Over time, species produce more offspring than their environment can support. The environment only has so much resources. Diseases and predators become more common as the population increases. The offspring are varied. |
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What causes variation in asexual organisms? |
Mutation |
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What causes variation in sexually reproducing organisms? |
Mutation; Meiosis; Random fertilization |
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What is mutation? |
a change in dna, usually during dna replication |
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How does meiosis introduce variation within a species? |
Crossing over and random orientation mix and match alleles originally from parents to make gametes |
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What is random fertilization? |
Random egg + Random sperm= recombination of allele from 2 parents |
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Describe the second step of evolution. |
Struggle for survival: Overproduction of offspring means that there aren't enough resources and/or there will be too many predators. To be evolutionarily successful, you just have to make lots of healthy babies. The successful combination of alleles will appear more often. |
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Describe the third step of evolution. |
Natural selection: nature selecting which phenotypes live and reproduce |
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What is an adaptation? |
Characteristics that make an individual suited to its environment |
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What is the survival of the fittest? |
Organisms with adaptations survive and pass on their traits to their offspring. Unfit organisms die out and so too do their traits |
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Describe the fourth step of evolution. |
Popular phenotypes arise: Over time the population is dominated by the popular phenotype. The frequency of these phenotypes increase. Frequency= percent or fraction |
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Are characteristics acquired during an organism's lifetime heritable? |
No. Only their DNA is heritable |
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On which Galapagos island were most of the studies on Darwin's finches conducted? |
Daphne Major |
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What did Darwin find when he examined the beaks of a group of closely related birds? |
He found that they came from a common ancestor but diverged into many species |
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The single species that Darwin's finches came from underwent what? |
Adaptive radiation |
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True or false: the common ancestor of Darwin's finches diverged into many species with different beak shapes and sizes to consume different food sources. |
True |
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What is the process by which bacteria become resistant to antibiotics? |
1) Bacteria reproduces and has variation due to mutation 2) Antibiotics are introduced 3) Mutation unintentionally produces variants who are resistant 4) These variants become successful and pass on their genes to their offspring |
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What is an example of an antibiotic resistant bacteria? |
MRSA (Methicillin resistant staphylococcus aureus) |
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What are two reasons to classify organisms? |
Identification, prediction of characteristics |
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What is taxonomy? |
The science of classifying organisms |
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What is a taxon? |
A level of classification (plural taxa) |
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True or false: there is a universal standard for naming organisms. |
True |
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What are the three domains? |
Archaea (prokaryotes); Eubacteria (also prokaryotes); Eukaryotes (can be either uni- or multi-cellular) |
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Organisms are placed into a _________ of classifications. |
Hierarchy |
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What is a hierarchy? |
Classification based on inclusiveness, categories are repeatedly divided and subdivided |
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Within the domain of eukaryotes, there are 7 more taxa. What are they? |
Kingdom, phylum, class, order, family, genus, species |
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If two species are in the same lower taxon, will they will be in all the same upper taxa as well? |
Yes |
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If two species have the same species name but they are in different genera, are they the same species? |
No |
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What is the universal standard for naming organisms called? |
Binomial nomenclature |
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Biologists had __________ where they got together and decided on names for organisms. |
Congresses |
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True or false: in the binomial system of nomenclature, you name organisms by their species followed by their genus |
False; in the binomial system of nomenclature, you name organisms by their genus followed by their species |
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What are the rules for writing organism's names? |
Always capitalize genus, never species; italicize if typing, underline of handwritten; can abbreviate genus by first letter |
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Organisms of the same genus have a very ______ common ancestor. |
Recent. They are closely related |
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True or false: organisms never get reclassified based on new DNA evidence. |
False; organisms sometimes get classified based on new DNA evidence |
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Is an organism's appearance sufficient to determine which organisms it is related to? |
No; similar DNA, and not necessarily similar appearance means more recent common ancestor |
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The vessels/tubes in an organism |
Vasculature (in plants xylem and phloem) |
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Describe the height, structure, main features, and reproduction of bryophytes. |
Mosses; can grow up to 50 cm; fuzzy, no wood or vasculature; reproduces using spores in capsules on stalks |
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Describe the height, structure, main features, and reproduction of filicinophytes. |
Ferns; can grow up to 20 m; curled leaves, have vasculature but no wood; reproduce using spores in capsules under leaves |
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Describe the height, structure, main features, and reproduction of coniferophytes. |
Conifers (pine trees, etc.); can grow up to 100 m; needles for leaves, wood and vasculature; reproduce using cones |
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Describe the height, structure, main features, and reproduction of angiospermophytes. |
Grasses, shrubs, trees that aren's conifers, etc.; Can grow up to 100 m; vasculature, can have wood; reproduce using fruits and flowers |
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Describe the Main features, symmetry, and segmentation of porifera. |
Sponges; porous for filter-feeding, sessile; no symmetry; no segmentation |
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Describe the Main features, symmetry, and segmentation of cnidaria. |
Jellies, anemones and corals; stinging cells, mouth but no anus; radial symmetry; no segmentation |
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Describe the Main features, symmetry, and segmentation of platyhelminthes. |
Flatworms such as tapeworms; mouth but no anus, flat, mostly parasitic; bilateral symmetry; no segmentation |
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Describe the Main features, symmetry, and segmentation of annelida. |
Segmented worms such as earthworms and leeches; can have bristles, have a mouth and an anus; bilateral symmetry; segmentation |
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Describe the Main features, symmetry, and segmentation of mollusca. |
Snails, octopi; usually has a shell, has a mouth and an anus; bilateral symmetry; segmentation |
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Describe the Main features, symmetry, and segmentation of arthropoda. |
Insects, arachnids, crustaceans; exoskeleton made of chitin, jointed limbs; bilateral symmetry; segmentation |
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Describe the Main features, symmetry, and segmentation of chordata. |
animals with a backbone; have a backbone; bilateral symmetry; segmentation |
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Are fish warm or cold-blooded? What is their method of circulation, ventilation, and reproduction? |
Cold-blooded; circulation is single-loop, 2-chambered heart; ventilate with gills; reproduce using eggs that develop externally |
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Are reptiles warm or cold-blooded? What is their method of circulation, ventilation, and reproduction? |
Cold-blooded; circulation is double-loop, 3-chambered heart (with mixing of oxygenated and deoxygenated blood in the third chamber); ventilate with lungs; reproduce using eggs |
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Are amphibians warm or cold-blooded? What is their method of circulation, ventilation, and reproduction? |
Cold-blooded; circulation is a single loop, 2-chambered heart as a juvenile, but is a double loop, 3-chambered heart (with mixing of oxygenated and de-oxygenated blood in the third chamber) as an adult; ventilate with gills as a juvenile, but with lungs with buccal breathing as an adult; reproduce using eggs |
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Are birds warm or cold-blooded? What is their method of circulation, ventilation, and reproduction? |
Warm-blooded; circulation is a double-loop, 4-chambered heart; ventilate with lungs and another air sac that can place air into hollow bones; reproduce with eggs |
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Are mammals warm or cold-blooded? What is their method of circulation, ventilation, and reproduction? |
Warm-blooded; circulation is a double-loop, 4-chambered heart; ventilate with lungs; reproduce by internal development of fetus, live birth, and nursing of young |
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What is a dichotomous key? |
a method of identifying an organism by answering a series of 2-choice questions |
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What is the science of identifying organisms based on common ancestry? |
Cladistics |
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What is a group of organisms that have evolved from a common ancestor? |
A clade |
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What is a tree diagram that shows the most probable sequence of divergence in clades? |
a cladogram |
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True or false: the more similar the pair of organisms, the more recent the common ancestor. |
True |
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What are the two methods of determining how similar 2 species are? |
1) DNA sequence for a gene 2) Resulting amino acid sequence |
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There is a ________ correlation between the number of differences between two species, and how long ago their common ancestor lived. |
Positive |
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True or false: as the number of differences between two species go up, the length of time since their common ancestor goes down. |
False; as the number of differences between two species go up, the length of time since their common ancestor goes up. |
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Homologous traits are evidence for a recent ______ ancestor. |
Common |
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What is divergent evolution? |
One common ancestor splitting into different species |
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Does divergent evolution give rise to homologous or analogous structures? |
Homologous structures |
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What are analogous traits? |
Traits among several species that use different structures for the same function. |
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What is an example of analogous structures? |
Birds in wings and insects |
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What is convergent evolution? |
Several unrelated species from different clades evolve the same function using different structures |
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Does convergent evolution give rise to homologous or analogous structures? |
Analogous structures |
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Describe the reclassification of the figwort family. |
Figwort family used to contain many genera because they all looked similar due to convergent evolution of flower shape. DNA evidence has shown that many of those genera are more related to other families so they got moved or put into a new family |