Coupled Reactions

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Paul Andersen explains the importance role of coupled reactions in biology. He starts by explaining how the power of a river can be harnessed by a water mill to grind grains. He describes the importance of ATP and how it is used within living organisms. He highlights many of the coupled reactions between the Sun and your thumb. He finishes the podcast by talking about REDOX reactions where oxidation is the losing of electrons and reduction is the gaining of these same electrons.

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Aposematic (Warning) Coloration

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Paul Andersen explains how aposematic coloration (or warning coloration) is used for protection in the natural world. He explains how bright colors can be caused by either sexual selection or a warning coloration to predators. He also explains how organisms can use this coloration to mimic other organisms with a similar pattern. He differentiates between Batesian and Müllerian mimicry.

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Mutations

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Paul Andersen describes the major mutations found in the living world. He starts with an analogy comparing the information in DNA with the information in a recipe. Changes in the DNA can result in changes to the protein, like changes in the recipe can result in changes in the food. He describes the three major point mutations; substitutions, deletions and insertions. He also describes several chromosomal mutations.

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Homeostatic Loops

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Paul Andersen describes four important homeostatic loops in biology. He begins with a brief description of the elements of a homeostatic loop. He then describes how the hypothalamus helps us maintain a stable internal body temperature. He explains the role of the pancreas (insulin and glucagon) in regulating blood glucose. He explains how the thyroid and parathyroid glands (along with calcitonin and PTH) regulation blood calcium. He also explains how the pituitary gland (and ADH) help regulate the osmolarity of the blood.
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Viruses

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Paul Andersen describes the important characteristics of viruses. He starts with a brief description of origin theories. He then describes the two characteristics of all viruses; genetic information and protein coats. He also describes how some viruses use specialized envelopes to gain entry to their host cells. He also explains the lytic and lysogenic reproductive cycles.
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Photosynthesis

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Paul Andersen explains the process of photosynthesis by which plants and algae can convert carbon dioxide into useable sugar. He begins with a brief description of the chloroplast. He describes the major pigments in a plant (like chlorophyll a and b). He then describes both the light reaction and the Calvin cycle. He finishes with a discussion of photorespiration and strategies for avoiding this problem evolved in CAM and C4 plants.
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Cellular Respiration

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Paul Andersen covers the processes of aerobic and anaerobic cellular respiration. He starts with a brief description of the two processes. He then describes the important parts of the mitochondria. He explains how energy is transferred to ATP through the processes of glycolysis, the Kreb cycle and the Electron Transport Chain. He also explains how organisms use both lactic acid and alcoholic fermentation.
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Bacteria

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Paul Andersen describes the defining characteristics of the domain Eubacteria. He begins with a quick description of the phylogeny of bacteria and horizontal gene transfer. He then surveys the structures of a bacteria; nucleoid region, capsule, pilli, cell wall with peptidoglycan, flagella. He describes the differing morphologies and metabolism in different bacteria. He describes how bacteria can be Gram positive or Gram negative. He finishes with a brief discussion of quorum sensing.
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Archaea

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In this video Paul Andersen describes the defining characteristics of members in the domain archaebacteria. He starts with a brief description of the phylogeny of this group. He then describes the major characteristics on an archaea, such as differences in the phospholipids. He explains how they reproduce through binary fission and finishes with a discussion of archaebacteria diversity.
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Eukarya

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Paul Andersen discusses the defining characteristics of the members of Domain Eukarya. He starts with a brief description of the phylogeny of life on earth. He then discusses the major characteristics of eukaryotic cells. He explains how eukaryotic cells evolved from prokaryotic cells using endosymbiosis and infolding. He finally discusses the metabolism and reproduction found in eukaryotes.
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