Biology Chapter 22: Descent with Modification
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Questions and Answers

What is the primary mechanism by which species adapt to different environments over time?

  • Genetic drift
  • Artificial selection
  • Mutation
  • Natural selection (correct)

    • Which scientist published the book 'The Origin of Species' in 1859?

  • Charles Lyell
  • Charles Darwin (correct)
  • Alfred Russell Wallace
  • James Hutton

    • What is the term for the process by which humans modify species through breeding only individuals with desired traits?

  • Artificial selection (correct)
  • Genetic engineering
  • Evolution
  • Natural selection

    • What is the main difference between homology and analogy?

    <p>Homology is due to shared ancestry, while analogy is due to convergent evolution</p> Signup and view all the answers

    What is the observation that all species can produce more offspring than the environment can support, and many of these offspring fail to survive and reproduce?

    <p>The struggle for existence</p> Signup and view all the answers

    What is a clade?

    <p>A group of organisms that are related to each other</p> Signup and view all the answers

    What is the term for the similarity between structures that are shared by different species due to common ancestry?

    <p>Homology</p> Signup and view all the answers

    What is a characteristic of prokaryotic cells?

    <p>They have a cell wall</p> Signup and view all the answers

    What is the main reason why humans and chimps share similar sequences of corresponding genes?

    <p>They share a recent common ancestor</p> Signup and view all the answers

    What provides the strongest evidence that all living organisms came from a common ancestor?

    <p>DNA</p> Signup and view all the answers

    What is the term for the process by which populations accumulate differences from their ancestors as they adapt to different environments over time?

    <p>Evolution</p> Signup and view all the answers

    What is the role of pili in prokaryotes?

    <p>To facilitate genetic recombination</p> Signup and view all the answers

    What is the scientific study of the geographic distribution of species?

    <p>Biogeography</p> Signup and view all the answers

    What is the term for the evolution of similar features in distantly related groups?

    <p>Convergent evolution</p> Signup and view all the answers

    What is the difference between bacteria and archaea?

    <p>Bacteria have a cell wall with peptidoglycan, while archaea do not</p> Signup and view all the answers

    Which of the following is an example of direct observation of evolution?

    <p>Antibiotic resistance in bacteria</p> Signup and view all the answers

    What is the role of prokaryotes in the environment?

    <p>They can be pathogens, mutualistic organisms, or decomposers</p> Signup and view all the answers

    What is the smallest scale of evolution?

    <p>Microevolution</p> Signup and view all the answers

    What is the term for the unequal ability of individuals to survive and reproduce, leading to the accumulation of favorable traits in a population over generations?

    <p>Differential reproduction</p> Signup and view all the answers

    Which scientist influenced Darwin's work on evolution?

    <p>Charles Lyell</p> Signup and view all the answers

    What is the cause of antibiotic resistance in bacteria?

    <p>Natural selection and evolution</p> Signup and view all the answers

    What is the term for the differences in genes or other DNA sequences among individuals?

    <p>Genetic variation</p> Signup and view all the answers

    What is the equation that describes the frequency of all alleles in a population?

    <p>p2 + 2pq + q2 = 1</p> Signup and view all the answers

    What is the function of the nucleoid in prokaryotes?

    <p>To store genetic material</p> Signup and view all the answers

    What type of selection is the process in which individuals with certain heritable traits are more likely to obtain mates than other individuals of the same sex?

    <p>Sexual selection</p> Signup and view all the answers

    What is the term for prokaryotes that can survive in extreme environments?

    <p>Extremophiles</p> Signup and view all the answers

    What is the process in which chance events cause allele frequencies to fluctuate unpredictably from one generation to the next?

    <p>Genetic drift</p> Signup and view all the answers

    What is the process by which prokaryotes reproduce?

    <p>Binary fission</p> Signup and view all the answers

    What is the term for the process by which one species splits into two species?

    <p>Speciation</p> Signup and view all the answers

    What is the term for the movement of alleles among populations?

    <p>Gene flow</p> Signup and view all the answers

    What is the main limitation of the morphological species concept?

    <p>It relies on subjective criteria</p> Signup and view all the answers

    What is the primary mechanism of prezygotic isolation?

    <p>Block fertilization</p> Signup and view all the answers

    Which type of speciation occurs in populations that live in the same geographic area?

    <p>Sympatric speciation</p> Signup and view all the answers

    What is the process by which a new species can form within a single generation without geographic separation?

    <p>Polyploidy</p> Signup and view all the answers

    What is the primary method used to date fossils?

    <p>Radiometric dating</p> Signup and view all the answers

    What is the term for the rapid period of evolutionary change where many new species arise and adapt to different ecological niches?

    <p>Adaptive radiation</p> Signup and view all the answers

    What is the hypothesis stating that mitochondria evolved before plastids through a sequence of endosymbiotic events?

    <p>Serial endosymbiosis</p> Signup and view all the answers

    What is the term for the evolutionary history of a species or group of related species?

    <p>Phylogeny</p> Signup and view all the answers

    What is the biological classification system that categorizes organisms into Domain, Kingdom, Phylum, Class, Order, Family, Genus, and Species?

    <p>Biological classification system</p> Signup and view all the answers

    What is the term for the process by which a species becomes extinct worldwide?

    <p>Mass extinction</p> Signup and view all the answers

    What is the primary way that prokaryotes obtain genetic variation?

    <p>Transformation</p> Signup and view all the answers

    What is the term for the similarity between structures that are shared by different species due to convergent evolution?

    <p>Analogy</p> Signup and view all the answers

    What is the term for a group that consists of an ancestral species and all of its descendants?

    <p>Monophyletic group</p> Signup and view all the answers

    What is the function of the capsule in prokaryotes?

    <p>To protect the cell from the environment</p> Signup and view all the answers

    What is the term for the process by which prokaryotes become resistant to antibiotics?

    <p>Natural selection</p> Signup and view all the answers

    What is the main difference between the cell walls of bacteria and archaea?

    <p>The presence of a peptidoglycan layer</p> Signup and view all the answers

    What is the term for the process by which prokaryotes exchange genetic material?

    <p>Conjugation</p> Signup and view all the answers

    What is the term for the study of the evolutionary history of a species or group of related species?

    <p>Phylogeny</p> Signup and view all the answers

    What is the term for the process by which populations accumulate differences from their ancestors as they adapt to different environments over time?

    <p>Macroevolution</p> Signup and view all the answers

    What is the term for the movement of alleles among populations?

    <p>Gene flow</p> Signup and view all the answers

    What is the main limitation of the biological species concept?

    <p>It is difficult to apply in fossils.</p> Signup and view all the answers

    What is the primary mechanism of postzygotic isolation that prevents hybrid zygotes from developing into fertile offspring?

    <p>Reduced hybrid viability</p> Signup and view all the answers

    What is the term for the process of speciation that occurs in populations that live in the same geographic area?

    <p>Sympatric speciation</p> Signup and view all the answers

    What is the term for the rapid period of evolutionary change where many new species arise and adapt to different ecological niches?

    <p>Adaptive radiation</p> Signup and view all the answers

    What is the term for the hypothesis stating that mitochondria evolved before plastids through a sequence of endosymbiotic events?

    <p>Serial endosymbiosis</p> Signup and view all the answers

    What is the primary method used to date fossils?

    <p>Radiometric dating</p> Signup and view all the answers

    What is the term for the study of the evolutionary history of a species or group of related species?

    <p>Phylogeny</p> Signup and view all the answers

    What is the term for the process by which a new species can form within a single generation without geographic separation?

    <p>Polyploidy</p> Signup and view all the answers

    What is the primary mechanism of prezygotic isolation that prevents members of two species from interbreeding and producing fertile offspring?

    <p>Mechanical isolation</p> Signup and view all the answers

    What is the term for the process in which species become extinct worldwide?

    <p>Mass extinction</p> Signup and view all the answers

    What is the primary reason for the existence of analogous traits in different species?

    <p>They are the result of similar environmental pressures.</p> Signup and view all the answers

    What is the term for the equation that describes the frequency of all alleles in a population?

    <p>Hardy-Weinberg Equation</p> Signup and view all the answers

    What is the process by which a few individuals become isolated from a larger population, leading to a loss of genetic variation?

    <p>Founder Effect</p> Signup and view all the answers

    What is the term for the process by which individuals with certain heritable traits are more likely to obtain mates than other individuals of the same sex?

    <p>Sexual Selection</p> Signup and view all the answers

    What is the term for the study of the geographic distribution of species?

    <p>Biogeography</p> Signup and view all the answers

    What is the primary mechanism that consistently causes adaptive evolution?

    <p>Natural Selection</p> Signup and view all the answers

    What is the term for the reduction of genetic variation in a population due to the random loss of alleles?

    <p>Genetic Drift</p> Signup and view all the answers

    What is the term for the process by which a population's allele frequencies change over time?

    <p>Microevolution</p> Signup and view all the answers

    What is the term for the movement of alleles from one population to another, leading to a change in allele frequencies?

    <p>Gene Flow</p> Signup and view all the answers

    What is the term for the process by which a new species forms from a single ancestral species?

    <p>Speciation</p> Signup and view all the answers

    What is the primary reason why populations, rather than individuals, are the units of evolution?

    <p>Only populations can accumulate genetic changes over time.</p> Signup and view all the answers

    What is the main difference between natural selection and artificial selection?

    <p>Natural selection occurs in the wild, whereas artificial selection occurs in a controlled environment.</p> Signup and view all the answers

    What is the primary reason why DNA provides strong evidence for evolution?

    <p>DNA sequences are similar among different species due to common ancestry.</p> Signup and view all the answers

    What is the main difference between anatomical homology and comparative embryology?

    <p>Anatomical homology refers to the structure of adult organisms, whereas comparative embryology refers to the development of embryos.</p> Signup and view all the answers

    What is the primary reason why antibiotic resistance is an example of direct observation of evolution?

    <p>Antibiotic resistance is a result of natural selection acting on bacterial populations.</p> Signup and view all the answers

    What is the primary reason why vestigial structures are evidence for evolution?

    <p>Vestigial structures are remnants of a common ancestor.</p> Signup and view all the answers

    What is the primary reason why the process of natural selection is not random?

    <p>Natural selection is a directed process that favors certain traits.</p> Signup and view all the answers

    What is the primary difference between observation and inference in the context of natural selection?

    <p>Observation is a direct measurement, whereas inference is an indirect measurement.</p> Signup and view all the answers

    What is the primary reason why the concept of evolution is not a scientific theory?

    <p>Evolution is a scientific theory because it is supported by multiple lines of evidence.</p> Signup and view all the answers

    What is the primary reason why the process of evolution is not a linear process?

    <p>Evolution is not a linear process because it occurs in a branching pattern.</p> Signup and view all the answers

    Which types of data document the pattern of evolution?

    <p>Biogeography</p> Signup and view all the answers

    What are vestigial structures?

    <p>Remnants of features that served a function in the organism's ancestors.</p> Signup and view all the answers

    Convergent evolution leads to traits that arise through common ancestry.

    <p>False</p> Signup and view all the answers

    Homologous structures are anatomical resemblances that represent variations on a structural theme present in a common ___.

    <p>ancestor</p> Signup and view all the answers

    Who published The Origin of Species in 1859, starting a scientific revolution in evolutionary biology?

    <p>Charles Darwin</p> Signup and view all the answers

    Jean-Baptiste de Lamarck's hypothesis of evolution includes the idea of inheritance of acquired characteristics.

    <p>True</p> Signup and view all the answers

    What is the process in which individuals with certain inherited traits tend to survive and reproduce at higher rates?

    <p>natural selection</p> Signup and view all the answers

    Darwin proposed __________ as an explanation for adaptation.

    <p>natural selection</p> Signup and view all the answers

    Match the following scientists with their contributions:

    <p>Georges Cuvier = Developed paleontology and observed that older strata contain fossils less similar to current organisms James Hutton = Proposed gradual formation of Earth's geologic features Charles Lyell = Proposed that same geologic processes operate today as in the past</p> Signup and view all the answers

    Who published The Origin of Species in 1859, starting the era of evolutionary biology?

    <p>Charles Darwin</p> Signup and view all the answers

    Darwin's theory of evolution is based on the idea of descent with modification.

    <p>True</p> Signup and view all the answers

    What did Charles Darwin propose as the mechanism for adaptation?

    <p>natural selection</p> Signup and view all the answers

    Darwin proposed that all organisms are related by descent from a common __________ that lived in the past.

    <p>ancestor</p> Signup and view all the answers

    What are the four types of data that document the pattern of evolution?

    <p>Direct observations</p> Signup and view all the answers

    Give an example of natural selection in response to introduced species.

    <p>Soapberry bugs developing longer beaks to feed on different fruit sizes in Florida.</p> Signup and view all the answers

    Convergent evolution results in analogous traits through common ancestry.

    <p>False</p> Signup and view all the answers

    Homology is similarity resulting from common ________.

    <p>ancestry</p> Signup and view all the answers

    Match the following characteristics with the correct description:

    <p>Vestigial structures = Remnants of features that served a function in ancestors Analogous structures = Evolution of similar features in distantly related groups Homologous structures = Anatomical resemblances that represent variations on a structural theme</p> Signup and view all the answers

    What is the term for the scientific study of the geographic distribution of species?

    <p>Biogeography</p> Signup and view all the answers

    What is the primary mechanism that consistently causes adaptive evolution?

    <p>Natural Selection</p> Signup and view all the answers

    What is the term for the evolution of similar features in distantly related groups?

    <p>Convergent Evolution</p> Signup and view all the answers

    What is the term for the process in which chance events cause allele frequencies to fluctuate unpredictably from one generation to the next?

    <p>Genetic Drift</p> Signup and view all the answers

    What is the term for the movement of alleles among populations?

    <p>Gene Flow</p> Signup and view all the answers

    What is the term for the process by which one species splits into two species?

    <p>Speciation</p> Signup and view all the answers

    What is the term for the differences in genes or other DNA sequences among individuals?

    <p>Genetic Variation</p> Signup and view all the answers

    What is the equation that describes the frequency of all alleles in a population?

    <p>p2 + 2pq + q2 = 1</p> Signup and view all the answers

    What is the term for the process in which individuals with certain heritable traits are more likely to obtain mates than other individuals of the same sex?

    <p>Sexual Selection</p> Signup and view all the answers

    What is the term for the process by which a population is not evolving, and genotype and allele frequencies remain constant from generation to generation?

    <p>Hardy-Weinberg Equilibrium</p> Signup and view all the answers

    What is the term for the scientific study of the origin of species?

    <p>Evolutionary Biology</p> Signup and view all the answers

    What is the main purpose of reproductive isolation?

    <p>To prevent interbreeding between different species</p> Signup and view all the answers

    What is the term for the process by which a new species can form within a single generation without geographic separation?

    <p>Polyploidy</p> Signup and view all the answers

    What is the term for the evolutionary history of a group of organisms?

    <p>Phylogeny</p> Signup and view all the answers

    What is the term for the process by which one species splits into two species?

    <p>Speciation</p> Signup and view all the answers

    What is the term for the rapid period of evolutionary change where many new species arise and adapt to different ecological niches?

    <p>Adaptive radiation</p> Signup and view all the answers

    What is the hypothesis stating that mitochondria evolved before plastids through a sequence of endosymbiotic events?

    <p>Serial endosymbiosis</p> Signup and view all the answers

    What is the primary method used to date fossils?

    <p>Radiometric dating</p> Signup and view all the answers

    What is the term for the process by which populations accumulate differences from their ancestors as they adapt to different environments over time?

    <p>Evolution</p> Signup and view all the answers

    What is the term for the study of the evolutionary history of a species or group of related species?

    <p>Phylogeny</p> Signup and view all the answers

    What is the biological classification system that categorizes organisms into Domain, Kingdom, Phylum, Class, Order, Family, Genus, and Species?

    <p>Linnaean system</p> Signup and view all the answers

    What is the primary mechanism by which individuals with certain inherited traits tend to survive and reproduce at higher rates?

    <p>Natural selection</p> Signup and view all the answers

    Which of the following is NOT an observation of natural selection?

    <p>Individuals with inherited traits that increase survival and reproduction in an environment produce fewer offspring</p> Signup and view all the answers

    What is the term for the process in which humans modify species through breeding only individuals with desired traits?

    <p>Artificial selection</p> Signup and view all the answers

    What is an example of direct observation of evolution?

    <p>Antibiotic resistance in bacteria</p> Signup and view all the answers

    What is the strongest evidence that all living organisms came from a common ancestor?

    <p>DNA</p> Signup and view all the answers

    Which scientist influenced Darwin's work on evolution?

    <p>Lyell</p> Signup and view all the answers

    What is the term for the process by which populations accumulate differences from their ancestors as they adapt to different environments over time?

    <p>Descent with modification</p> Signup and view all the answers

    What is the term for the similarity between structures that are shared by different species due to common ancestry?

    <p>Homology</p> Signup and view all the answers

    What is the term for the process in which individuals with certain inherited traits tend to produce more offspring than other individuals?

    <p>Natural selection</p> Signup and view all the answers

    What is the term for the observation that all species can produce more offspring than the environment can support, and many of these offspring fail to survive and reproduce?

    <p>Overproduction and struggle for existence</p> Signup and view all the answers

    What is the main difference between homologous and analogous structures?

    <p>Homologous structures are similar in function, while analogous structures are similar in structure.</p> Signup and view all the answers

    Which of the following is an example of a monophyletic group?

    <p>A group consisting of an ancestral species and all of its descendants.</p> Signup and view all the answers

    What is the primary function of pili in prokaryotes?

    <p>To facilitate genetic recombination.</p> Signup and view all the answers

    Which of the following is a characteristic of extremophiles?

    <p>They are found in extreme environments.</p> Signup and view all the answers

    What is the primary mechanism of genetic recombination in prokaryotes?

    <p>All of the above.</p> Signup and view all the answers

    Which of the following is a characteristic of polyphyletic groups?

    <p>They consist of distantly related species but not their most recent common ancestor.</p> Signup and view all the answers

    What is the primary function of the capsule in prokaryotes?

    <p>To facilitate cell-cell interactions.</p> Signup and view all the answers

    Which of the following is a characteristic of prokaryotic cells?

    <p>They have a plasma membrane.</p> Signup and view all the answers

    What is the primary mechanism of antibiotic resistance in prokaryotes?

    <p>Natural selection.</p> Signup and view all the answers

    Which of the following is a characteristic of archaea?

    <p>They are extremophiles.</p> Signup and view all the answers

    What is the term used to refer to all eukaryotes that are not plants, animals, or fungi?

    <p>Protist</p> Signup and view all the answers

    Which group of protists includes Trypanosoma and Euglena?

    <p>Excavata</p> Signup and view all the answers

    What is the term for a relationship between two species in which one organism lives inside the cell or cells of the other organism?

    <p>Endosymbiosis</p> Signup and view all the answers

    What is the characteristic of protists that indicates they are nutritionally diverse?

    <p>They can be photoautotrophs, heterotrophs, or mixotrophs</p> Signup and view all the answers

    Which group of protists includes Diatoms and brown algae?

    <p>SAR</p> Signup and view all the answers

    What is the name of the protist that causes malaria?

    <p>Plasmodium</p> Signup and view all the answers

    What is the main characteristic that distinguishes fungi from plants?

    <p>Cell walls made of chitin</p> Signup and view all the answers

    What is the function of mycelium in fungi?

    <p>To absorb nutrients from the environment</p> Signup and view all the answers

    What is the term for the mutually beneficial relationship between fungi and plant roots?

    <p>Mycorrhiza</p> Signup and view all the answers

    What is the characteristic that distinguishes plants from algae?

    <p>Alternation of generations</p> Signup and view all the answers

    What is the function of root hairs?

    <p>To increase the surface area for absorbing minerals and water</p> Signup and view all the answers

    What is the main function of the xylem?

    <p>To conduct water and dissolved minerals upward from roots to shoots</p> Signup and view all the answers

    What is the term for the process of pollination in plants?

    <p>Pollination</p> Signup and view all the answers

    What is the main difference between seeds and spores?

    <p>Seeds are multicellular, while spores are single-celled</p> Signup and view all the answers

    What is the term for the process by which seeds develop?

    <p>Double Fertilization</p> Signup and view all the answers

    What is the function of the ovary in a flower?

    <p>To produce the female reproductive cell</p> Signup and view all the answers

    What is the term for the structure specialized for sexual reproduction in angiosperms?

    <p>Flower</p> Signup and view all the answers

    What is the term for the group of plants that include conifers, such as pines, firs, and redwoods?

    <p>Gymnosperms</p> Signup and view all the answers

    What is the term for the symbiotic interaction between fungi and plant roots?

    <p>Mycorrhizal Association</p> Signup and view all the answers

    What is the term for the process by which plants adapt to different environments over time?

    <p>Evolution</p> Signup and view all the answers

    What is the function of the stamen?

    <p>To produce the male reproductive cell</p> Signup and view all the answers

    What is the term for the process by which plants adapt to dispersed seeds?

    <p>Seed Dispersal</p> Signup and view all the answers

    What is the term for the study of the geographic distribution of species?

    <p>Biogeography</p> Signup and view all the answers

    What is the function of the phloem?

    <p>To transport sugars from leaves to roots</p> Signup and view all the answers

    What is the term for the type of plant tissue that provides flexible support without restraining growth?

    <p>Collenchyma</p> Signup and view all the answers

    What is the term for the pores necessary to allow diffusion of CO2 into the photosynthetic tissues of leaves?

    <p>Stomata</p> Signup and view all the answers

    What is the primary function of aquaporins in the cell membrane?

    <p>Facilitate the passage of water</p> Signup and view all the answers

    Which of the following is NOT a macronutrient essential for plant growth?

    <p>Iron</p> Signup and view all the answers

    What is the primary function of rhizobium in the soil?

    <p>Nitrogen fixation</p> Signup and view all the answers

    What is the term for the association between fungi and the roots of plants?

    <p>Mycorrhizae</p> Signup and view all the answers

    What is the primary function of the carpel in a flower?

    <p>To contain the ovules</p> Signup and view all the answers

    What is the term for the process by which pollen is transferred from the anther to the stigma?

    <p>Pollination</p> Signup and view all the answers

    What is the term for the process by which a sperm fertilizes an egg, and another sperm combines with the polar nuclei?

    <p>Double fertilization</p> Signup and view all the answers

    What is the primary benefit of genetically modified plants?

    <p>Reduced crop disease</p> Signup and view all the answers

    What is the term for the reproduction of offspring from a single parent without the fusion of egg and sperm?

    <p>Asexual reproduction</p> Signup and view all the answers

    What is the term for the process by which an organism produces offspring that are genetically identical to the parent?

    <p>Asexual reproduction</p> Signup and view all the answers

    What is the main characteristic of Arthropods?

    <p>Segmented body, exoskeleton, jointed appendages, and open circulatory system</p> Signup and view all the answers

    What is the main characteristic of Chordates?

    <p>Bilateral, deuterostome development, and notochord</p> Signup and view all the answers

    What is the function of Fibroblasts?

    <p>Secrete fiber proteins</p> Signup and view all the answers

    What is the function of Macrophages?

    <p>Engulf foreign particles</p> Signup and view all the answers

    What is the main characteristic of Amniotes?

    <p>Tetrapods, and amniotic eggs</p> Signup and view all the answers

    What is the function of the hypothalamus?

    <p>Physiological thermostat</p> Signup and view all the answers

    What is the main characteristic of Epithelial tissue?

    <p>Covers the outside of the body and lines the organs and cavities within the body</p> Signup and view all the answers

    What is the main characteristic of Nematodes?

    <p>Have hemocoel</p> Signup and view all the answers

    What is the main characteristic of Echinoderms?

    <p>Water vascular system, and tube feet</p> Signup and view all the answers

    What is the main characteristic of Deuterostomes?

    <p>Formation of the anus from the blastopore, and radial cleavage</p> Signup and view all the answers

    What is a characteristic shared by all animals?

    <p>Ability to move and capture prey</p> Signup and view all the answers

    What is the significance of the Cambrian explosion?

    <p>It is a period of rapid animal diversification</p> Signup and view all the answers

    What is the main difference between radial and bilateral symmetry?

    <p>Radial symmetry allows for faster movement, while bilateral symmetry allows for sensory organs and a central nervous system</p> Signup and view all the answers

    What is the blastula in animal development?

    <p>A stage in embryonic development where a hollow ball of cells forms</p> Signup and view all the answers

    What is the main difference between protostomes and deuterostomes?

    <p>Protostomes have a blastopore that becomes the mouth, while deuterostomes have a blastopore that becomes the anus</p> Signup and view all the answers

    What is the characteristic that defines invertebrates?

    <p>Absence of a backbone</p> Signup and view all the answers

    What is the characteristic that defines porifera (sponges)?

    <p>They have no tissues and filter feed</p> Signup and view all the answers

    What is the characteristic that defines chordata?

    <p>They have a backbone and are vertebrates</p> Signup and view all the answers

    What is the main characteristic of lophotrochozoans?

    <p>They have a lophophore for feeding</p> Signup and view all the answers

    What is the characteristic that defines molluscs?

    <p>They have a muscular foot and visceral mass</p> Signup and view all the answers

    What is the functional unit of the vertebrate kidney?

    <p>Nephron</p> Signup and view all the answers

    What is the role of ADH in the kidney?

    <p>Reduce urine volume</p> Signup and view all the answers

    What type of hormone is oxytocin?

    <p>Polypeptide</p> Signup and view all the answers

    What is the role of the hypothalamus in the endocrine system?

    <p>Regulates hormone secretion</p> Signup and view all the answers

    What is the term for the process by which the response reduces the initial stimulus?

    <p>Negative feedback</p> Signup and view all the answers

    What is the region of the nephron where water and solutes are filtered from the blood?

    <p>Glomerulus</p> Signup and view all the answers

    What is the term for the communication and control system in animals that uses hormones?

    <p>Endocrine system</p> Signup and view all the answers

    What is the hormone that stimulates the release of milk in response to suckling?

    <p>Oxytocin</p> Signup and view all the answers

    What is the term for the hormones produced by the anterior pituitary?

    <p>Anterior pituitary hormones</p> Signup and view all the answers

    What is the term for the process by which the body maintains a stable internal environment?

    <p>Homeostasis</p> Signup and view all the answers

    Which type of circulatory system do insects, other arthropods, and some molluscs have?

    <p>Open circulatory system</p> Signup and view all the answers

    What is the function of capillaries in the human cardiovascular system?

    <p>Where chemical exchanges occur</p> Signup and view all the answers

    What is the difference between the heart of amphibians and that of mammals?

    <p>Number of chambers</p> Signup and view all the answers

    What is the function of platelets in the human circulatory system?

    <p>Involved in clotting</p> Signup and view all the answers

    What is the difference between positive and negative pressure breathing?

    <p>Direction of air flow</p> Signup and view all the answers

    What is the function of Malpighian tubules in insects and other terrestrial arthropods?

    <p>Remove nitrogenous wastes from hemolymph</p> Signup and view all the answers

    What is the function of interferons in innate immunity?

    <p>Provide innate defense by inhibiting the replication of viruses</p> Signup and view all the answers

    What is the term for the process by which the body regulates solute concentrations and balances water gain and loss?

    <p>Osmoregulation</p> Signup and view all the answers

    What is the function of the kidney in vertebrates?

    <p>Excretion and osmoregulation</p> Signup and view all the answers

    What is the difference between urea and uric acid?

    <p>Toxicity</p> Signup and view all the answers

    Study Notes

    Chapter 22: Descent with Modification

    • Scientists who influenced Darwin: Hutton, Cuvier, Lyell, Wallace
    • Darwin's voyage on the HMS Beagle and publication of "The Origin of Species" in 1859
    • Definition of evolution: the process by which species accumulate differences from their ancestors as they adapt to different environments over time
    • Population changes over time genetically, not individually
    • Natural selection: the process in which individuals with certain inherited traits tend to survive and reproduce at higher rates
    • 4 observations of natural selection:
      • Individuals in populations vary in their inherited traits
      • All species can produce more offspring than the environment can support
      • Individuals with inherited traits that increase survival and reproduction in an environment tend to produce more offspring
      • The unequal ability of individuals to survive and reproduce will lead to the accumulation of favorable traits in the population over generations
    • Artificial selection: humans modifying species through breeding individuals with desired traits

    Evidence of Evolution

    • Direct observation: antibiotic resistance, birds' beak size and fruit size
    • Homology: similarity from common ancestry
      • Anatomical homology: homologous structures
      • Comparative embryology
      • Vestigial structures: goosebumps, wisdom teeth, ear muscle, tailbone of human
      • Molecular homology: DNA
    • Fossil records: the age of fossil records is about 3.5 billion years ago
    • Biogeography: the scientific study of the geographic distribution of species (continental drift and the distribution of modern living organisms)

    Homologous vs. Analogous Structures

    • Analogous traits: result of similar environments (not due to common ancestry)
    • Convergent evolution: the evolution of similar features in distantly related groups
    • Examples: dolphin and shark body shapes, sugar glider and flying squirrel

    Chapter 23: The Evolution of Populations

    • Macroevolution vs. microevolution
    • Microevolution: changes in allele frequencies in populations over generations
    • Three mechanisms that cause allele frequency change:
      • Natural selection
      • Genetic drift
      • Gene flow
    • Genetic variation: the differences in genes or other DNA sequences among individuals
    • Sources of genetic variation:
      • Mutation
      • Gene duplication
      • Sexual reproduction
    • Gene pool: consists of all copies of every allele in all members of the population

    Hardy-Weinberg Equilibrium

    • If a population is not evolving, genotype and allele frequencies will be constant from generation to generation
    • Equilibrium conditions:
      • No mutation
      • Random mating
      • No natural selection
      • Extremely large population size
      • No gene flow
    • Hardy-Weinberg equation: p + q = 1
    • Applying the equation: need to work on practice questions

    Natural Selection

    • Natural selection is the only mechanism that consistently causes adaptive evolution
    • Relative fitness: the contribution an individual makes to the gene pool of the next generation relative to the contributions of other individuals
    • Patterns of natural selection:
      • Directional
      • Disruptive
      • Stabilizing
    • Sexual selection: a process in which individuals with certain heritable traits are more likely to obtain mates than other individuals of the same sex
    • Heterozygote advantage: occurs when heterozygotes have a higher fitness than both kinds of homozygotes

    Genetic Drift

    • A process in which chance events cause allele frequencies to fluctuate unpredictably from one generation to the next
    • Tends to reduce genetic variation through the random loss of alleles
    • The smaller the sample, the greater the chance of random deviation from a predicted result
    • Founder effect: occurs when a few individuals become isolated from a larger population
    • Bottleneck effect: occurs when there is a drastic reduction in population size due to a sudden change in the environment

    Gene Flow

    • Consists of the movement of alleles among populations
    • Can lead to genetic variation and change in populations

    Chapter 24: The Origin of Species

    • Speciation: the process by which one species splits into two species
    • Microevolution vs. macroevolution: macroevolution refers to broad patterns of evolutionary change above the species level
    • Biological species concept: defined by the populations' ability to interbreed and produce fertile offspring
    • Morphological species concept: mainly depends on anatomical physical features
    • Ecological species concept: defines species by its ecological niche

    Reproductive Isolation

    • Results when biological barriers impede members of two species from interbreeding and producing fertile offspring
    • Prezygotic and postzygotic isolations
    • Prezygotic isolation:
      • Habitat isolation
      • Temporal isolation
      • Behavioral isolation
      • Mechanical isolation
      • Gametic isolation
    • Postzygotic isolation:
      • Reduced hybrid viability
      • Reduced hybrid fertility
      • Hybrid breakdown

    Speciation

    • Two ways of speciation: allopatric vs. sympatric speciation
    • Allopatric speciation: populations are geographically isolated
    • Sympatric speciation: speciation occurs in populations that live in the same geographic area
    • Polyploidy: instant speciation, common in plants
    • Sexual selection: speciation is driven by mate choice for certain traits
    • Habitat differentiation: the exploitation of new habitats or resources

    Chapter 25: The History of Life on Earth

    • The formation of earth: about 4.6 billion years ago
    • The oldest prokaryote fossils: 3.5 billion years ago
    • The oldest eukaryote fossils: 1.8 billion years ago
    • The first genetic material on earth: more likely RNA
    • Radiometric dating: how fossils are dated, using radioactive isotope
    • Geologic record: Cambrian explosion (Many animal phyla appear suddenly in the fossils of the Cambrian period)

    Endosymbiosis

    • Origin of eukaryotic organisms
    • Both mitochondria and plastids are thought to have descended from bacteria
    • Serial endosymbiosis: the hypothesis stating that mitochondria evolved before plastids through a sequence of endosymbiotic events

    Mass Extinctions

    • Occur when large numbers of species rapidly become extinct worldwide
    • Five mass extinctions have been documented
    • Paved the way for adaptive radiation (a rapid period of evolutionary change where many new species arise and adapt to different ecological niches)

    Chapter 26: Phylogeny and the Tree of Life

    • Phylogeny: the evolutionary history of a species or group of related species
    • Phylogenetic tree: the evolutionary history of a group of organisms can be represented in a branching diagram
    • Biological classification system:
      • Domain-Kingdom-Phylum- Class-Order-Family-Genus-Species
      • Binomial nomenclature: by Carolus Linnaeus in the 18th century

    Homology vs. Analogy

    • Homology is similarity due to shared ancestry
    • Analogy is similarity due to convergent evolution

    Phylogenetic Tree

    • Only monophyletic groups, consisting of the ancestor and all of its descendants, are clades
    • A paraphyletic group consists of an ancestral species and some, but not all, of the descendants
    • A polyphyletic group includes distantly related species but not their most recent common ancestor

    Chapter 27: Bacteria and Archaea

    • Prokaryotes:
      • Single-celled organisms that make up domains Bacteria and Archaea
      • First organisms to inhabit Earth
      • Most are unicellular but some species form colonies
      • Smaller and simpler than eukaryotic cells
      • Shapes: cocci, bacilli, spirals
      • Structures: nucleoid, plasmid, pili, fimbriae, capsule, ribosome
    • Reproduce quickly by binary fission
    • Genetic recombination by transformation, transduction, conjugation
    • Different ways to obtain energy:
      • Phototrophs
      • Chemotrophs
      • Autotrophs
      • Heterotrophs
    • Two domains with prokaryotes: bacteria and archaea
    • Bacteria: gram positive vs. negative, Cyanobacteria are photosynthetic
    • Archaea: extremophiles (live in extreme environments), methanogens
    • The commonalities and differences between bacteria and archaea
    • The roles of prokaryotes:
      • Pathogen
      • Mutualistic organisms
      • Decomposers

    Descent with Modification

    • Scientists who influenced Darwin: Hutton, Cuvier, Lyell, Wallace, etc.
    • Darwin's 5-year voyage on the HMS Beagle as a naturalist led to the publication of "The Origin of Species" in 1859
    • Definition of evolution: the process by which species accumulate differences from their ancestors as they adapt to different environments over time
    • Populations change over time genetically, not individuals

    Natural Selection

    • The process by which individuals with certain inherited traits tend to survive and reproduce at higher rates because of those traits
    • 4 observations (or inferences) of natural selection:
      • Individuals in populations vary in their inherited traits
      • All species can produce more offspring than the environment can support, leading to a struggle for existence
      • Individuals with inherited traits that increase survival and reproduction in an environment tend to produce more offspring
      • The unequal ability of individuals to survive and reproduce will lead to the accumulation of favorable traits in the population over generations
    • Artificial selection: humans can modify species through breeding only individuals with desired traits

    Evidence of Evolution

    • Direct observation: antibiotic resistance, birds' beak size and fruit size
    • Homology: similarity from common ancestry, including:
      • Anatomical homology (homologous structures)
      • Comparative embryology
      • Vestigial structures (e.g. goosebumps, wisdom teeth, ear muscle, tailbone of humans)
      • Molecular homology (DNA)
    • DNA provides strong evidence that all living organisms came from a common ancestor
    • Fossil records: age of fossil records is about 3.5 billion years old
    • Biogeography: the scientific study of the geographic distribution of species, including continental drift and the distribution of modern living organisms

    Homologous vs. Analogous Structures

    • Analogous traits are the result of similar environments, not common ancestry (convergent evolution)
    • Examples of analogous structures: streamlined body shapes of dolphin and shark, sugar glider of Australia and flying squirrel of North America
    • Examples of homologous structures: wings of birds and forelimbs of mammals (e.g. flippers of whales)

    Microevolution vs. Macroevolution

    • Microevolution: changes in allele frequencies in populations over generations, evolution at its smallest scale
    • Macroevolution: broad patterns of evolutionary change above the species level, the formation of new species

    Mechanisms of Evolution

    • Three mechanisms that directly cause allele frequency change:
      • Natural selection
      • Genetic drift
      • Gene flow
    • Genetic variation: the differences in genes or other DNA sequences among individuals, required for a population to evolve
    • Sources of genetic variation: mutation, gene duplication, sexual reproduction

    Hardy-Weinberg Equilibrium

    • If a population is not evolving, genotype and allele frequencies will be constant from generation to generation
    • Equilibrium conditions: no mutation, random mating, no natural selection, extremely large population size, no gene flow
    • In real populations, allele and genotype frequencies often do change over time
    • Hardy-Weinberg equation: p + q = 1, p² + 2pq + q² = 1

    Natural Selection

    • The only mechanism that consistently causes adaptive evolution
    • Relative fitness: the contribution an individual makes to the gene pool of the next generation relative to the contributions of other individuals
    • Patterns of natural selection: directional, disruptive, and stabilizing
    • Sexual selection: a process in which individuals with certain heritable traits are more likely to obtain mates than other individuals of the same sex
    • Heterozygote advantage: occurs when heterozygotes have a higher fitness than both kinds of homozygotes

    Genetic Drift

    • A process in which chance events cause allele frequencies to fluctuate unpredictably from one generation to the next
    • Tends to reduce genetic variation through the random loss of alleles
    • The smaller the sample, the greater the chance of random deviation from a predicted result
    • Founder effect: occurs when a few individuals become isolated from a larger population
    • Bottleneck effect: occurs when there is a drastic reduction in population size due to a sudden change in the environment

    Gene Flow

    • Consists of the movement of alleles among populations
    • Causes allele frequencies to change in a population

    Speciation

    • The process by which one species splits into two species
    • Microevolution vs. macroevolution: macroevolution refers to broad patterns of evolutionary change above the species level
    • Biological species concept: defined by the populations' ability to interbreed and produce fertile offspring
    • Morphological species concept: mainly depends on anatomical physical features
    • Ecological species concept: defines species by its ecological niche

    Reproductive Isolation

    • Results when biological barriers impede members of two species from interbreeding and producing fertile offspring
    • Prezygotic and postzygotic isolations
    • Prezygotic isolation: block fertilization, including:
      • Habitat isolation
      • Temporal isolation
      • Behavioral isolation
      • Mechanical isolation
      • Gametic isolation
    • Postzygotic isolation: occurs after fertilization, including:
      • Reduced hybrid viability
      • Reduced hybrid fertility
      • Hybrid breakdown

    Speciation

    • Two ways of speciation: allopatric vs. sympatric speciation
    • Allopatric speciation: populations are geographically isolated
    • Sympatric speciation: speciation occurs in populations that live in the same geographic area
    • Polyploidy: instant speciation, a process that can form a new species within a single generation without geographic separation
    • Sexual selection: speciation is driven by mate choice for certain traits
    • Habitat differentiation: the exploitation of new habitats or resources

    The History of Life on Earth

    • The formation of earth: about 4.6 billion years ago
    • The oldest prokaryote fossils: 3.5 billion years ago
    • The oldest eukaryote fossils: 1.8 billion years ago
    • The first genetic material on earth: RNA (self-replication, central roles in protein synthesis, catalytic ability)
    • Radiometric dating: how fossils are dated, using radioactive isotopes
    • Geologic record: Cambrian explosion (many animal phyla appear suddenly in the fossils of the Cambrian period)

    Endosymbiosis

    • Origin of eukaryotic organisms
    • Both mitochondria and plastids are thought to have descended from bacteria
    • Serial endosymbiosis: the hypothesis stating that mitochondria evolved before plastids through a sequence of endosymbiotic events
    • Evidence: mitochondria and plastids are similar to bacterial cells in their membrane protein, replication mechanisms, DNA structures, ribosomes, RNA sequence, etc.

    Mass Extinctions

    • Occur when large numbers of species rapidly become extinct worldwide
    • Five mass extinctions have been documented
    • Paved the way for adaptive radiation (a rapid period of evolutionary change where many new species arise and adapt to different ecological niches)

    Phylogeny and the Tree of Life

    • Phylogeny: the evolutionary history of a species or group of related species
    • Phylogenetic tree: a branching diagram that represents the evolutionary history of a group of organisms
    • Biological classification system: Domain-Kingdom-Phylum-Class-Order-Family-Genus-Species
    • Binomial nomenclature: by Carolus Linnaeus in the 18th century

    Bacteria and Archaea

    • Prokaryotes: single-celled organisms that make up domains Bacteria and Archaea
    • First organisms to inhabit Earth
    • Most are unicellular but some species form colonies
    • Smaller and simpler than eukaryotic cells
    • Shapes: cocci, bacilli, spirals
    • Structures: nucleoid, plasmid, pili, fimbriae, capsule, ribosome
    • Reproduce quickly by binary fission
    • Genetic recombination by transformation, transduction, conjugation
    • Different ways to obtain energy: phototrophs, chemotrophs, autotrophs, heterotrophs
    • Two domains with prokaryotes: bacteria and archaea

    Bacteria and Archaea

    • Bacteria: gram positive vs. negative, Cyanobacteria are photosynthetic
    • Archaea: extremophiles (live in extreme environments), methanogens
    • The commonalities and differences between bacteria and archaea
    • Both have a plasma membrane, no nuclear envelope
    • Different composition of cell wall (most bacterial cell walls contain peptidoglycan while Archaeal walls lack this material)
    • The roles of prokaryotes: pathogen, mutualistic organisms, decomposers

    Descent with Modification: A Darwinian View of Life

    • Charles Darwin's publication of "The Origin of Species" in 1859 started a scientific revolution in evolutionary biology
    • Darwin's ideas developed gradually, influenced by other works and his own travels

    Evolution

    • Evolution refers to the process by which species accumulate differences from their ancestors as they adapt to different environments over time
    • Evolution can be viewed as both a pattern and a process
    • The pattern is revealed by scientific data showing that life has evolved over time
    • The process consists of the mechanisms that cause the pattern of change
    • Descent with modification is a phrase summarizing Darwin's view of life

    Scala Naturae and Classification of Species

    • Greek philosopher Aristotle believed that species were fixed and unchanging
    • Aristotle arranged species on a scale of increasing complexity called the scala naturae
    • Carolus Linnaeus developed a nested classification system grouping similar species into increasingly inclusive categories
    • Binomial format for naming species (e.g., Homo sapiens) is still in use today

    Ideas About Change over Time

    • Fossils provide evidence of species that have changed over time
    • Paleontology, the study of fossils, was developed in large part by Georges Cuvier
    • Cuvier observed that older strata contain fossils less similar to current organisms than more recent strata
    • Cuvier speculated that boundaries between strata represent sudden catastrophic events
    • Darwin was influenced by scientists proposing that slow, continuous processes caused change on Earth
    • James Hutton and Charles Lyell proposed that Earth's geologic features were formed gradually
    • Darwin reasoned that the Earth must be older than the widely accepted age of a few thousand years
    • If true, gradual processes could also account for substantial biological change

    Lamarck's Hypothesis of Evolution

    • Jean-Baptiste de Lamarck proposed two principles to explain evolutionary change
      • Use and disuse: body parts used extensively become larger and stronger, unused parts deteriorate
      • Inheritance of acquired characteristics: modifications acquired in one's lifetime can be passed to offspring
    • This mechanism is not supported by experimental evidence

    Darwin's Research

    • Charles Darwin had a consuming interest in nature throughout his life
    • He studied medicine and theology before taking a position as naturalist on the HMS Beagle
    • During his travels on the Beagle, Darwin collected specimens of South American plants and animals
    • He noted that fossils resembled living species from the area in which they were found, and living species resembled other species from areas nearby
    • On the Galápagos Islands, Darwin collected many similar but different species of birds, some unique to individual islands
    • Animals unique to the islands resembled species on the nearby mainland of South America
    • Darwin hypothesized that species from the mainland colonized and diversified on the islands

    Descent with Modification

    • Darwin used descent with modification to describe his view of life
    • All organisms are related by descent from a common ancestor that lived in the past
    • Related organisms living in different habitats gradually accumulated diverse modifications to fit them to specific ways of life
    • Large morphological gaps between related groups are explained by branching and extinction events

    Artificial Selection, Natural Selection, and Adaptation

    • Humans modify species through artificial selection, breeding only individuals with desired traits
    • Crops, livestock animals, and pets often bear little resemblance to their wild ancestors
    • Natural selection is a process in which individuals with inherited traits that increase survival and reproduction in an environment tend to survive and reproduce at higher rates

    Key Features of Natural Selection

    • Individuals with certain heritable traits survive and reproduce at a higher rate than other individuals
    • Natural selection increases the frequency of adaptations that are favorable in an environment
    • If the environment changes, natural selection may drive adaptation to new conditions, giving rise to new species

    Evolution is Supported by Scientific Evidence

    • Direct observations of evolutionary change

    • Homology, similarity resulting from common ancestry

      • Anatomical and molecular homologies
        • Vestigial structures are remnants of features that served a function in the organism's ancestors
      • Molecular homologies, including the genetic code shared by all life

    • The fossil record provides evidence of the extinction of species, the origin of new groups, and changes within groups over time

    • Biogeography, the scientific study of the geographic distribution of species, provides support for evolution### Understanding Continental Drift and Species Distribution

    • The study of continental drift and modern species distribution helps predict when and where different groups evolved

    • Freshwater fish in the family Galaxiidae live in South America and Australia, separated by wide stretches of open ocean

    • These fish species share a common ancestor dating back to the time when the continents broke away from Pangea

    Characteristics of a Scientific Theory

    • A scientific theory accounts for many observations and data
    • A theory attempts to explain and integrate a great variety of phenomena
    • Darwin's theory of evolution by natural selection integrates diverse areas of biological study
    • The theory stimulates many new research questions
    • Ongoing research adds to our understanding of evolution

    Descent with Modification: A Darwinian View of Life

    • Charles Darwin's publication of "The Origin of Species" in 1859 started a scientific revolution in evolutionary biology
    • Darwin's ideas developed gradually, influenced by other works and his own travels

    Evolution

    • Evolution refers to the process by which species accumulate differences from their ancestors as they adapt to different environments over time
    • Evolution can be viewed as both a pattern and a process
    • The pattern is revealed by scientific data showing that life has evolved over time
    • The process consists of the mechanisms that cause the pattern of change
    • Descent with modification is a phrase summarizing Darwin's view of life

    Scala Naturae and Classification of Species

    • Greek philosopher Aristotle believed that species were fixed and unchanging
    • Aristotle arranged species on a scale of increasing complexity called the scala naturae
    • Carolus Linnaeus developed a nested classification system grouping similar species into increasingly inclusive categories
    • Binomial format for naming species (e.g., Homo sapiens) is still in use today

    Ideas About Change over Time

    • Fossils provide evidence of species that have changed over time
    • Paleontology, the study of fossils, was developed in large part by Georges Cuvier
    • Cuvier observed that older strata contain fossils less similar to current organisms than more recent strata
    • Cuvier speculated that boundaries between strata represent sudden catastrophic events
    • Darwin was influenced by scientists proposing that slow, continuous processes caused change on Earth
    • James Hutton and Charles Lyell proposed that Earth's geologic features were formed gradually
    • Darwin reasoned that the Earth must be older than the widely accepted age of a few thousand years
    • If true, gradual processes could also account for substantial biological change

    Lamarck's Hypothesis of Evolution

    • Jean-Baptiste de Lamarck proposed two principles to explain evolutionary change
      • Use and disuse: body parts used extensively become larger and stronger, unused parts deteriorate
      • Inheritance of acquired characteristics: modifications acquired in one's lifetime can be passed to offspring
    • This mechanism is not supported by experimental evidence

    Darwin's Research

    • Charles Darwin had a consuming interest in nature throughout his life
    • He studied medicine and theology before taking a position as naturalist on the HMS Beagle
    • During his travels on the Beagle, Darwin collected specimens of South American plants and animals
    • He noted that fossils resembled living species from the area in which they were found, and living species resembled other species from areas nearby
    • On the Galápagos Islands, Darwin collected many similar but different species of birds, some unique to individual islands
    • Animals unique to the islands resembled species on the nearby mainland of South America
    • Darwin hypothesized that species from the mainland colonized and diversified on the islands

    Descent with Modification

    • Darwin used descent with modification to describe his view of life
    • All organisms are related by descent from a common ancestor that lived in the past
    • Related organisms living in different habitats gradually accumulated diverse modifications to fit them to specific ways of life
    • Large morphological gaps between related groups are explained by branching and extinction events

    Artificial Selection, Natural Selection, and Adaptation

    • Humans modify species through artificial selection, breeding only individuals with desired traits
    • Crops, livestock animals, and pets often bear little resemblance to their wild ancestors
    • Natural selection is a process in which individuals with inherited traits that increase survival and reproduction in an environment tend to survive and reproduce at higher rates

    Key Features of Natural Selection

    • Individuals with certain heritable traits survive and reproduce at a higher rate than other individuals
    • Natural selection increases the frequency of adaptations that are favorable in an environment
    • If the environment changes, natural selection may drive adaptation to new conditions, giving rise to new species

    Evolution is Supported by Scientific Evidence

    • Direct observations of evolutionary change

    • Homology, similarity resulting from common ancestry

      • Anatomical and molecular homologies
        • Vestigial structures are remnants of features that served a function in the organism's ancestors
      • Molecular homologies, including the genetic code shared by all life

    • The fossil record provides evidence of the extinction of species, the origin of new groups, and changes within groups over time

    • Biogeography, the scientific study of the geographic distribution of species, provides support for evolution### Understanding Continental Drift and Species Distribution

    • The study of continental drift and modern species distribution helps predict when and where different groups evolved

    • Freshwater fish in the family Galaxiidae live in South America and Australia, separated by wide stretches of open ocean

    • These fish species share a common ancestor dating back to the time when the continents broke away from Pangea

    Characteristics of a Scientific Theory

    • A scientific theory accounts for many observations and data
    • A theory attempts to explain and integrate a great variety of phenomena
    • Darwin's theory of evolution by natural selection integrates diverse areas of biological study
    • The theory stimulates many new research questions
    • Ongoing research adds to our understanding of evolution

    Descent with Modification

    • Scientists who influenced Darwin: Hutton, Cuvier, Lyell, Wallace, etc.
    • Darwin's 5-year voyage on the HMS Beagle and publication of "The Origin of Species" in 1859
    • Definition of evolution: the process by which species accumulate differences from their ancestors as they adapt to different environments over time
    • Populations change over time genetically, not individuals

    Natural Selection

    • The process in which individuals with certain inherited traits tend to survive and reproduce at higher rates because of those traits
    • 4 observations of natural selection:
      • Individuals in populations vary in their inherited traits
      • All species can produce more offspring than the environment can support, and many of these offspring fail to survive and reproduce
      • Individuals with inherited traits that increase survival and reproduction in an environment tend to produce more offspring than other individuals
      • The unequal ability of individuals to survive and reproduce will lead to the accumulation of favorable traits in the population over generations
    • Artificial selection: humans can modify species through breeding only individuals with desired traits

    Evidence of Evolution

    • Direct observation: antibiotic resistance, birds' beak size and fruit size
    • Homology: similarity from common ancestry
      • Anatomical homology (homologous structures)
      • Comparative embryology
      • Vestigial structures (e.g. goosebumps, wisdom teeth, ear muscle, tailbone of human)
      • Molecular homology (DNA)
    • Fossil records: 3.5 billion years ago
    • Biogeography: the scientific study of the geographic distribution of species (continental drift and the distribution of modern living organisms)

    Evolution of Populations

    • Microevolution vs. macroevolution
    • Three mechanisms that cause allele frequency change:
      • Natural selection
      • Genetic drift
      • Gene flow
    • Genetic variation: the differences in genes or other DNA sequences among individuals
      • Sources of genetic variation: mutation, gene duplication, sexual reproduction
    • Gene pool: consists of all copies of every allele in all members of the population
    • Hardy-Weinberg Equilibrium:
      • If a population is not evolving, genotype and allele frequencies will be constant from generation to generation
      • Equilibrium conditions: no mutation, random mating, no natural selection, extremely large population size, no gene flow

    Natural Selection (continued)

    • Relative fitness: the contribution an individual makes to the gene pool of the next generation relative to the contributions of other individuals
    • Patterns of natural selection:
      • Directional
      • Disruptive
      • Stabilizing
    • Sexual selection: a process in which individuals with certain heritable traits are more likely to obtain mates than other individuals of the same sex
    • Heterozygote advantage: occurs when heterozygotes have a higher fitness than both kinds of homozygotes (e.g. sickle cell anemia)

    Genetic Drift

    • A process in which chance events cause allele frequencies to fluctuate unpredictably from one generation to the next
    • Tends to reduce genetic variation through the random loss of alleles
    • The smaller the sample, the greater the chance of random deviation from a predicted result
    • Founder effect: occurs when a few individuals become isolated from a larger population
    • Bottleneck effect: occurs when there is a drastic reduction in population size due to a sudden change in the environment

    Gene Flow

    • Consists of the movement of alleles among populations

    Origin of Species

    • Speciation: the process by which one species splits into two species
    • Microevolution vs. macroevolution
    • Biological species concept:
      • Defined by the populations' ability to interbreed and produce fertile offspring
      • Limitations: cannot be applied to fossils or asexual organisms
    • Morphological species concept:
      • Mainly depends on anatomical physical features
      • Not as accurate as the biological species concept, but still useful in fossil data, asexual species, and species that we can't observe their reproductive activity
    • Ecological species concept: defines species by its ecological niche

    Reproductive Isolation

    • Results when biological barriers impede members of two species from interbreeding and producing fertile offspring
    • Prezygotic and postzygotic isolations
    • Prezygotic isolation:
      • Habitat isolation
      • Temporal isolation
      • Behavioral isolation
      • Mechanical isolation
      • Gametic isolation
    • Postzygotic isolation:
      • Reduces hybrid viability
      • Reduces hybrid fertility
      • Hybrid breakdown

    Speciation

    • Two ways of speciation: allopatric vs. sympatric speciation
    • Allopatric speciation: populations are geographically isolated
    • Sympatric speciation: speciation occurs in populations that live in the same geographic area
    • Polyploidy: instant speciation, common in plants
    • Sexual selection: speciation is driven by mate choice for certain traits
    • Habitat differentiation: the exploitation of new habitats or resources

    History of Life on Earth

    • Formation of earth: about 4.6 billion years ago
    • Oldest prokaryote fossils: 3.5 billion years ago
    • Oldest eukaryote fossils: 1.8 billion years ago
    • The first genetic material on earth: likely RNA
    • Radiometric dating: how fossils are dated, using radioactive isotopes (e.g. Carbon 14)
    • Geologic record: Cambrian explosion (many animal phyla appear suddenly in the fossils of the Cambrian period)
    • Endosymbiosis:
      • Origin of eukaryotic organisms
      • Serial endosymbiosis: the hypothesis stating that mitochondria evolved before plastids through a sequence of endosymbiotic events

    Phylogeny and the Tree of Life

    • Phylogeny: the evolutionary history of a species or group of related species
    • Phylogenetic tree: represents the evolutionary history of a group of organisms in a branching diagram
    • Biological classification system:
      • Domain-Kingdom-Phylum-Class-Order-Family-Genus-Species
      • Binomial nomenclature: by Carolus Linnaeus in the 18th century
    • Homology vs. Analogy:
      • Homology is similarity due to shared ancestry
      • Analogy is similarity due to convergent evolution
    • Phylogenetic tree:
      • Only monophyletic groups, consisting of the ancestor and all of its descendants, are clades
      • A paraphyletic group consists of an ancestral species and some, but not all, of the descendants
      • A polyphyletic group includes distantly related species but not their most recent common ancestor

    Bacteria and Archaea

    • Prokaryotes: single-celled organisms that make up domains Bacteria and Archaea
    • Characteristics:
      • Smaller and simpler than eukaryotic cells
      • Shapes: cocci, bacilli, spirals
      • Structures: nucleoid, plasmid, pili, fimbriae, capsule, ribosome
      • Reproduce quickly by binary fission
      • Genetic recombination by transformation, transduction, conjugation
      • Different ways to obtain energy: phototrophs, chemotrophs, autotrophs, heterotrophs
    • Two domains with prokaryotes: Bacteria and Archaea
    • Commonalities and differences between Bacteria and Archaea:
      • Both have a plasma membrane, no nuclear envelope
      • Different composition of cell wall (peptidoglycan in bacteria, lacking in archaea)
    • Roles of prokaryotes: pathogens, mutualistic organisms, decomposers

    Protists

    • An informal term for eukaryotes that are not plants, animals, or fungi
    • Characteristics:
      • Have a nucleus and membrane-enclosed organelles
      • Most are unicellular, but some are multicellular
      • Nutritionally diverse (photoautotrophs, heterotrophs, mixotrophs)
    • Endosymbiosis: a relationship between two species where one organism lives inside the cell or cells of the other
    • 4 groups:
      • Excavata (Trypanosoma, Euglena)
      • SAR (Diatoms, brown algae, water molds, Dinoflagellates, Plasmodium, Paramecium)
      • Archaeplastida (red and green algae, Charophytes, Volvox)
      • Unikonta (Amoeba, slime mold)

    Fungi

    • Heterotrophs that absorb nutrients from outside their bodies
    • Characteristics:
      • Mostly multicellular, but some are unicellular (e.g., yeast)
      • Cell walls made of chitin
      • Sexual and asexual reproduction
    • Body structure:
      • Hyphae: tubular cell walls strengthened with chitin, divided into cells by septa
      • Mycelium: an interwoven mass formed by hyphae, maximizing surface area for absorption
    • Roles:
      • Decomposers
      • Mutualists
      • Pathogens (e.g., ringworm, yeast infection)
      • Medicine (e.g., penicillin)

    Mutualism of Fungi

    • Mycorrhiza: mutually beneficial relationships between fungi and plant roots
    • Lichen: symbiotic associations between photosynthetic microorganisms and fungi
    • Fungus-farming ants: some fungi share digestive services with animals

    Plant Diversity

    • Role of plants: oxygen production, food sources, habitat for land organisms
    • Similarities between plants and green algae:
      • Multicellular, eukaryotic, photosynthetic autotrophs
      • Cellulose cell walls
      • Chloroplasts
    • Differences:
      • Alternation of generations
      • Walled spores produced in sporangia
      • Apical meristems
      • Cuticle and stomata unique to plants

    Evolution of Plants

    • From cyanobacteria to green algae to land plants
    • Four groups of plants:
      • Nonvascular plants (Bryophytes, Mosses)
      • Seedless vascular plants (ferns)
      • Gymnosperms (naked seeds)
      • Angiosperms (flowers, double fertilization, nearly 90% of living plants)

    Seed Plants

    • Sporophyte-dominated life cycle
    • Characteristics:
      • Reduced gametophytes
      • Heterospory
      • Ovules
      • Pollen
    • Pollination: transfer of pollen to ovules
    • Seeds:
      • Consist of embryo and nutrients surrounded by a coat
      • Can remain dormant for years
      • Can be transported long distances by wind or animals
    • Gymnosperms:
      • Naked seeds exposed on sporophylls (e.g., conifers)
    • Angiosperms:
      • Seed plants with reproductive structures called flowers and fruits
      • 90% of all plants

    Plant Structure

    • Hierarchical organization: cell – tissue – organ – organism
    • Plant organs:
      • Roots (root system)
      • Stems and leaves (shoot system)
    • Root functions:
      • Anchoring the plant
      • Absorbing minerals and water
      • Storing carbohydrates
    • Stem functions:
      • Elongating and orienting the shoot
      • Maximizing photosynthesis
    • Leaf functions:
      • Main photosynthetic organ
      • Exchanging gases
      • Defending against herbivores and pathogens

    Plant Tissues

    • Dermal tissue: protective outer coating
    • Vascular tissue: facilitates transport of materials and provides mechanical support
    • Ground tissue: specialized cells for storage, photosynthesis, and support
    • Meristem tissue: for growth and development

    Plant Cells

    • Parenchyma: performs most metabolic functions
    • Collenchyma: provides flexible support
    • Sclerenchyma: rigid cells with secondary cell walls containing lignin
    • Water-conducting cells of the xylem: tracheids, vessel elements
    • Sugar-conducting cells of the phloem: sieve-tube elements, companion cells

    Resource Acquisition and Transport

    • Xylem: transports water and minerals from roots to shoots
    • Phloem: transports photosynthetic products from where they are made to where they are needed
    • Stomata: pores necessary for CO2 diffusion into photosynthetic tissues
    • Mycorrhizae: fungal associations increase surface area for absorbing water and minerals
    • Aquaporins: transport proteins facilitating water passage across cell membranes

    Soil and Plant Nutrition

    • Essential elements: 17 chemical elements required for plant life cycle
    • 9 macronutrients: required in large amounts
    • 8 micronutrients: required in small amounts
    • Plant mutualism with soil bacteria: rhizobacteria and endophyte
    • Nitrogen fixation: required for plants to acquire nitrogen as nitrate

    Angiosperm Reproduction

    • Angiosperm anatomy:
      • Flowers: reproductive shoots of the angiosperm sporophyte
      • Four parts of flowers: carpels, stamens, petals, sepals
    • Angiosperm life cycle:
      • Gametophyte development
      • Sperm delivery by pollen tubes
      • Double fertilization
      • Seed development
    • Pollination: transfer of pollen from anthers to stigma
    • Double fertilization: fusion of gametes
    • Fruits: mature ovary of a flower, protects seeds and aids in seed dispersal

    Chapter 32: Animal Diversity

    • Common characteristics of animals: can move and capture prey, multicellular, no cell walls, heterotrophic, eukaryotes
    • Animals evolved from flagellated protists, with choanoflagellates as the closest living relatives
    • The Cambrian explosion marks a period of rapid animal diversification
    • Animal body plan: radial symmetry vs. bilateral symmetry, with most animals evolving to have bilateral symmetry for faster movement and formation of a head with sensory organs and central nervous system

    Embryo Development

    • Animal zygotes undergo cleavage, a succession of cell divisions without growth between divisions
    • Cleavage leads to the formation of a blastula, often in the form of a hollow ball of cells

    Animal Tissues

    • Only a few groups have no tissue (e.g., sponges)
    • Most animals have germ layers that give rise to the tissues and organs (diploblastic: ectoderm and endoderm/triploblastic: ectoderm, endoderm, and mesoderm)
    • Body cavity: coelom (a cavity surrounded by tissues derived from mesoderm), hemocoel (filled with hemolymph), or no cavity at all (e.g., flatworms)

    Protostome vs. Deuterostome Development

    • In protostome development, the blastopore becomes the mouth
    • In deuterostomes, the blastopore becomes the anus (e.g., echinoderms and chordates)

    Chapter 33: Invertebrate Animals

    • Invertebrates: animals without a backbone
    • Porifera (sponges): simplest animals, filter feeders, no tissue
    • Cnidarians: true tissues, gastrovascular cavity, polyps and medusa life forms, nematocysts, radial symmetry
    • Lophotrochozoans: have a lophophore for feeding or a trochophore larval stage
    • Flatworms (platyhelminthes): flat body form for large surface area (e.g., planarians, tapeworms)
    • Molluscs: muscular foot, visceral mass, mantle (major groups: Gastropoda, Bivalvia, Cephalopoda)
    • Annelids: segmented worms, have a coelom (e.g., leeches, earthworms)
    • Ecdysozoans: cuticle, molting
    • Nematodes: have hemocoel (e.g., roundworms)
    • Arthropods: segmented body, exoskeleton, jointed appendages, open circulatory system with heart and hemolymph (example groups: Pancrustaceans including insects, Chelicerates, Myriapods)
    • Deuterostomes: formation of the anus from the blastopore, radial cleavage
    • Echinoderms: water vascular system, tube feet

    Chapter 34: Vertebrate Animals

    • Common characteristic of chordates: bilateral, deuterostome development, mostly vertebrates with two groups of invertebrates
    • Four characteristics of chordate embryos: notochord, dorsal nerve cord, pharyngeal pouches (slits), post-anal tail
    • Chordates:
      • Lancelet, tunicates: invertebrates
      • Hagfishes and lampreys: lacking jaws
      • Sharks and rays: oil in the liver to maintain buoyancy
      • Ray-finned and lobe-fin fish: swim bladder for buoyancy
      • Amphibians: need water and land for living, metamorphosis, frogs, and salamanders
      • Reptiles: scales, shelled and amniotic eggs, ectothermic
      • Birds: endothermic, direct descendants of dinosaurs
      • Mammals: mammary glands, hair, endothermy (high metabolic rate)

    Chapter 40: Animal Form and Function

    • Tissues: groups of cells with a similar appearance and function
    • Four types of tissues:
      • Epithelial tissue: covers the outside of the body and lines the organs and cavities within the body
      • Connective tissue: holds many tissues and organs together in place (e.g., tendons, ligaments, bone, adipose tissue, blood)
      • Muscle tissue:
        • Skeletal muscle: responsible for voluntary movement
        • Smooth muscle: responsible for involuntary body activities such as digestive system movement or uterus contraction
        • Cardiac muscle: responsible for contraction of the heart (striated with intercalated disc)
      • Nervous tissue: functions in the receipt, processing, and transmission of information

    Homeostasis

    • Automatic tendency to maintain a constant and optimal internal environment
    • Positive and negative feedback

    Chapter 41: Animal Nutrition

    • Variation in diet: herbivores, carnivores, omnivores
    • Food processing: ingestion, digestion, absorption, and elimination
    • Most complex animals have a digestive tube with two openings (alimentary canal)
    • Advantages of having a complete digestive system: specialized regions with diverse functions
    • Digestive system in human:
      • Oral cavity: salivary glands, amylase which breaks down starch
      • Pharynx: the junction that opens to the esophagus and the trachea
      • Esophagus: connects to the stomach, food is pushed to the stomach by peristalsis (by alternating waves of smooth muscle contraction), valves called sphincters regulate the movement of material between compartments
      • Stomach: gastric juice, chyme, breaks down proteins, mucus protects the stomach lining
      • Small intestine: most enzymatic hydrolysis of macromolecules occurs here (pancreas produces trypsin and chymotrypsin, bile facilitates fat digestion (made by liver and stored in gall bladder), huge surface area due to villi and microvilli
      • Large intestine: absorbs water and salts, includes colon, cecum, and rectum

    Chapter 42: Circulation and Respiration

    • Open and closed circulatory system
    • Insects, other arthropods, and some molluscs: open circulatory systems with hemolymph
    • Annelids, cephalopods, and vertebrates: closed circulatory systems
    • Human cardiovascular system:
      • Heart
      • Blood vessels:
        • Arteries: carry blood away from the heart to capillaries
        • Veins: return blood from capillaries to the heart
        • Capillaries: where chemical exchanges occur
      • Blood:
        • Plasma: liquid matrix
        • Platelets: fragments of cells involved in clotting
        • Red blood cells (erythrocytes): transport oxygen
        • White blood cells (leukocytes): defense

    Chapter 43: Immune System

    • Examples of pathogens: agents that cause disease such as viruses, bacteria, fungi
    • Innate immunity:
      • Non-specific, active immediately upon infection
      • Barrier defenses (skin, mucus, body fluids)
      • Cellular defense (neutrophils, macrophages, dendritic cells, eosinophils, natural killer cells)
      • Inflammation: histamine triggers blood vessels to dilate and become more permeable
      • Interferons: provide innate defense by inhibiting the replication of viruses
    • Adaptive immunity:
      • Activated after the innate response
      • Develops more slowly
      • Enhanced by previous exposure to the pathogen
      • T cells (mature in thymus)
      • B cells (mature in bone marrow)

    Chapter 44: Osmoregulation

    • Osmoregulation: controls solute concentrations and balances water gain and loss
    • Animal’s nitrogenous waste: consumption of proteins and nucleic acids causes nitrogenous waste
    • Excretory systems:
      • Filtration: filtering of body fluids
      • Reabsorption: recovering valuable solutes
      • Secretion: adding nonessential solutes and wastes to the filtrate
      • Excretion: processed filtrate containing nitrogenous wastes is released from the body
    • Kidney: the excretory organs of vertebrates and some other chordates, function in excretion and osmoregulation
    • Nephrons: the functional units of the vertebrate kidney

    Chapter 45: Hormones

    • Hormone: a secreted molecule that circulates through the body and stimulates specific cells
    • Communication and control in animals:
      • Endocrine system: chemical signaling by hormones
      • Nervous system: a network of specialized cells (neurons) that transmit signals along dedicated pathways
    • Feedback regulation:
      • Negative feedback: the response reduces the initial stimulus (more common)
      • Positive feedback: reinforces a stimulus to produce an even greater response (e.g., oxytocin causes the release of milk, causing greater suckling by offspring, which stimulates the release of more oxytocin)
    • Hypothalamus: coordinates endocrine signaling, signals from the hypothalamus travel to the pituitary gland
    • Posterior pituitary: stores and secretes hormones that are made in the hypothalamus
    • Anterior pituitary: makes and releases hormones under regulation of the hypothalamus

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    This quiz covers the concepts of evolution, natural selection, and the influences on Charles Darwin's theory of descent with modification, including his voyage on the HMS Beagle and the publication of 'The Origin of Species' in 1859.

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