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It's a mark of how extraordinary a step Darwin proposed the idea – that random mutations would make some species better suited to their environments than others, and that those species would be more likely to breed –Natural selection and survival of the fittest and common descent. Number 1.

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  1. It's a mark of how extraordinary a step Darwin proposed the idea – that random mutations would make some species better suited to their environments than others, and that those species would be more likely to breed –Natural selection and survival of the fittest and common descent. Number 1

  2. Number 2 • In evolutionary biology, a group of organisms share common descent if they have a common ancestor. There is strong quantitative support for the theory that all living organisms on Earth are descended from a common ancestor • Natural selection the process whereby organisms better adapted to their environment tend to survive and produce more offspring.

  3. Number 3 • Adaptation -- when an organism becomes better matched with its current environment . Adaptations can be structural (meaning an organism undergoes bodily changes to survive) or behavioral (when a specific behavior increases an organism's chances of survival). • Examples: birds migrating south for the winter or animals using tools to forage for food, occur at the individual and population levels. • Environmental factors -- including competition for resources, predation, infectious diseases, climate and seasonality -- play a large role

  4. Number 3 continued • Believe it or not, our skin has an adaptation of its own -- tanning. Humans adapt to the sun's ultraviolet rays through the production of melanin, the pigment that gives skin its color . Melanin shields deeper layers of the skin and prevents the sun's harmful rays from breaking down folic acid, an important vitamin that repairs blood cells in the body

  5. Number 4 • Structural evidence..like teeth • Embryonic development..developing embryos all have same features depending on ancestry • Genetic evidence-DNA matches

  6. Number 5 • We did not cover this in class….so read carefully and summarize the examples • Speciation is the changing of individuals within a population so they are no longer part of the same species. This most often occurs due to geographic isolation or reproductive isolation of individuals within the population. As the species evolve and branch off, they cannot interbreed with members of the original species any longer.

  7. Number 5 continued • There are 3 main types of speciation that can occur based on reproductive or geographic isolation, among other reasons and environmental factors • Allopatric (allo = other, patric = place) Geographically isolated populations. The Isolation might occur because of great distance or a physical barrier, such as a desert or river, as shown below.

  8. Number 5 continued • Parapatric (para = beside, patric = place) • a continuously distributed population that for various reasons only mate with certain parts of the population thus not spreading certain genes. • Example: Some of these plants live near mines where the soil has become contaminated with heavy metals. The plants around the mines have experienced natural selection for genotypes that are tolerant of heavy metals. Meanwhile, neighboring plants that don’t live in polluted soil have not undergone selection for this trait. The two types of plants are close enough that tolerant and non-tolerant individuals could potentially fertilize each other—so they seem to meet the first requirement of parapatric speciation, that of a continuous population. However, the two types of plants have evolved different flowering times. This change could be the first step in cutting off gene flow entirely between the two group

  9. Number 5 continued • Sympatric (sym = same, patric = place) • within the range of the population but environmental factors keep then mating only with specific mates. • Example: 200 years ago, the ancestors of apple maggot flies laid their eggs only on hawthorns—but today, these flies lay eggs on hawthorns (which are native to America) and domestic apples (which were introduced to America by immigrants and bred). Females generally choose to lay their eggs on the type of fruit they grew up in, and males tend to look for mates on the type of fruit they grew up in. So hawthorn flies generally end up mating with other hawthorn flies and apple flies generally end up mating with other apple flies. This host shift from hawthorns to apples may be the first step toward sympatric speciation—in fewer than 200 years, some genetic differences between these two groups of flies have evolved.

  10. Number 6The highest taxonomic rank of organisms in which there are three groupings: Archaea, Bacteria and Eukarya

  11. Number 7 • A phylogeny, or evolutionary tree, or cladogram represents the evolutionary relationships among a set of organisms or groups of organisms, called taxa (singular: taxon).

  12. Number 8 • Species share similarities that are signs of their common ancestry. Bones structure of whale fin and human hand or all insects have 6 legs. • There are progressions of species changing over time for example species that lived in the past are very often drastically, wildly different from anything alive today. Dinosaurs, giant sloths etc. • Species have traits that are the remnants or left overs of past generations. Vestigial organs like the appendix . • Embryological development

  13. Number 8 continued • This a manatee flipper which still has nails from toes it no longer needs.

  14. Number 9 • Energy flow occurs within cells. • Heredity information (DNA) is passed on from cell to cell. • All cells have the same basic chemical composition • Cell is the basic unit of life • All living things are made of cells

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  16. As organisms evolved to become multicellular, diffusion of materials into and out of the organism was no longer an efficient way to exchange materials with the environment (or among the cells inside). As a result, certain cells became "specialized" to perform more specific jobs. The larger and more complex organisms became, the more important it was for cells to take on special jobs. A good analogy is a manufacturing business- if it's small, a few workers can do several jobs to make a product. However, if it's a large factory, each of the many workers must learn to specialize in doing one thing. This is called "division of labor."

  17. Number 19 Active transport takes place in the small intestine during digestion. Passive transport is gas exchange in the lungs

  18. Number 25 Interphase is made up of three distinct phases: G1, S phase, and G2. The G1 and G2 phases serve as checkpoints for the cell to make sure that it is ready to proceed in the cell cycle. If it is not, the cell will use this time to make proper adjustments that can include cell growth, correction or completion of DNA synthesis, and duplication of intracellular components. S phase involves the replication of chromosomes. All three stages of interphase involve continued cell growth and an increase in the concentration of proteins found in the cell.

  19. Number 26 Prophase Chromatin in the nucleus begins to condense and becomes visible in the light microscope as chromosomes. The nucleolus disappears. Centrioles begin moving to opposite ends of the cell and fibers extend from the centromeres. Some fibers cross the cell to form the mitotic spindle. Metaphase Spindle fibers align the chromosomes along the middle of the cell nucleus. This line is referred to as the metaphase plate. This organization helps to ensure that in the next phase, when the chromosomes are separated, each new nucleus will receive one copy of each chromosome. Anaphase The paired chromosomes separate at the kinetochores and move to opposite sides of the cell. Motion results from a combination of kinetochore movement along the spindle microtubules and through the physical interaction of polar microtubules.

  20. Number 26 continued Telophase Chromatids arrive at opposite poles of cell, and new membranes form around the daughter nuclei. The chromosomes disperse and are no longer visible under the light microscope. The spindle fibers disperse, and cytokinesis or the partitioning of the cell may also begin during this stage. Cytokinesis In animal cells, cytokinesis results when a fiber ring composed of a protein called actin around the center of the cell contracts pinching the cell into two daughter cells, each with one nucleus. In plant cells, the rigid wall requires that a cell plate be synthesized between the two daughter cells.

  21. Number 26

  22. Number 27 Asexual: - allows for a quick "doubling" of populations (faster) - less energy required for reproduction - daughter offspring look exactly and have the same genetic material as the parent - lack of genetic variation - population may go extinct with dramatic changes in environment Sexual: - allows for genetic variation due to the joining of two different individuals- less population growth - slower process - requires long-term energy use

  23. Number 28 Prophase I, Crossing-Over - homologous pairs join together (synapsis) and exchange genetic informationExchange of DNA during prophase I increases genetic variability. Chromatids are no longer exact duplicates. Metaphase I, chromosomes line up in PAIRS, but they line up randomly which allows for a phenomenon known as INDEPENDENT ASSORTMENT

  24. Number 28 continued Crossing-over of homologous chromosomes (recombines the maternally- and paternally-derived chromosomes to create new allele combinations). Random segregation of homologous chromosomes (the maternally- and paternally-derived chromosomes will go randomly into the two daughter cells during meiosis I). Random segregation of the sister chromatids during meiosis II (in mitosis, sister chromatids are identical, but due to crossing-over, in meiosis, they're not, so random segregation of them is another way there's increased variation).

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  32. Number 36 Gregor Mendel, through his work on pea plants, discovered the fundamental laws of inheritance. He deduced that genes come in pairs and are inherited as distinct units, one from each parent. Mendel tracked the segregation of parental genes and their appearance in the offspring as dominant or recessive traits. He recognized the mathematical patterns of inheritance from one generation to the next. Mendel's Laws of Heredity are usually stated as: 1) The Law of Segregation: Each inherited trait is defined by a gene pair. Parental genes are randomly separated to the sex cells so that sex cells contain only one gene of the pair. Offspring therefore inherit one genetic allele from each parent when sex cells unite in fertilization.

  33. Number 36 continued 2) The Law of Independent Assortment: Genes for different traits are sorted separately from one another so that the inheritance of one trait is not dependent on the inheritance of another. 3) The Law of Dominance: An organism with alternate forms of a gene will express the form that is dominant.

  34. Number 37 Phenotype: This is the "outward, physical manifestation" of the organism. These are the physical parts, structures, metabolism, energy utilization, tissues, organs, reflexes and behaviors; anything that is part of the observable structure, function or behavior of a living organism. Examples: hair color, five fingers, curly hair, diseases etc.

  35. Number 37 continued Genotype: This is the "internally coded, inheritable information" carried by all living organisms. This stored information is used as a "blueprint" or set of instructions for building and maintaining a living creature. These instructions are found within almost all cells. These instructions are intimately involved with all aspects of the life of a cell or an organism. They control everything from the formation of protein macromolecules, to the regulation of metabolism and synthesis. A= white hair a= red hair Genotype AA, Aa, aa Phenotype white hair or red hair

  36. Number 38 M=orange m=cream

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