r and K Selection

Paul Andersen explains the differences between an r and a K selected species. He starts with a brief description of population growth noting the importance of; r or growth rate, N or number of individuals in the population, and K the carrying capacity. He describes three different survivorship curves found in organisms. He lists the characteristics of r-selected species like bacteria and K-selected species like humans.
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Coevolution

Paul Andersen explains the concept of coevolution. He begins with an analogy comparing the relationship of humans to technology with those of coevolving species. He then discriminates between coevolution and convergent evolution. He finishes by describing many symbiotic relationships that formed through coevolution. The rough skinned newt and the garter snake, the acacia tree and the acacia ant, and finally all the symbiotic relationships utilized by leaf cutter ants.
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Molecular Biology

Paul Andersen explains the major procedures in molecular biology. He starts with a brief description of Taq polymerase extracted from the hot pools of Yellowstone Park. He then uses the analogy of the ransom note to explain each of the processes that are required in genetic engineering. He explains how DNA is cut using restriction enzymes and glued using hydrogen bonds. He explains how gel electrophoresis can be used to sort DNA according to length and how the Polymerase Chain Reaction can be used to copy DNA. He finishes with a brief description of DNA sequencing.

 

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Osmoregulation

Paul Andersen explains how organisms regulate their internal osmolarity or not. He starts with a brief description of osmosis and why it is important for animal cell to be surrounded by an isotonic solution. He then explains how freshwater and saltwater fish osmoregulate. He finally discussed the nephron within the kidney as an osmoregulatory organ. He explains how the loop of Henle sets up a gradient which is used to reclaim or remove water with the use of the antidiuretic hormone (or ADH).

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The Endocrine System

Paul Andersen explains the major elements in the endocrine system. He explains how glands produce hormones which target cells. He differentiates between water soluble and lipid soluble hormones. He then describes the hormones and actions of ten glands; pineal, anterior pituitary, posterior pituitary, thyroid, parathyroid, pancreas, adrenal cortex, adrenal medulla, testes and ovaries.

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The Immune System

Paul Andersen explains how your body protects itself from invading viruses and bacteria. He starts by describing the nonspecific immune responses of skin and inflammation. He then explains how we use antibodies to disrupt the function of antigens and mark them for destruction. He then explains both the homoral and cell-mediated immune response highlighting the importance of B and T lymphocytes. He finally describes the process of long term immunity.

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The Respiratory System

Paul Andersen starts this video with a description of the respiratory surface. He explains how worms, insects, fish and mammals take in oxygen and release carbon dioxide. He then tours the major organs of the respiratory system; from the pharynx to the trachea, bronchus, bronchiole and alveoli. He also explains how oxygen is carried on the hemoglobin and how carbon dioxide is carried as bicarbonate.

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AP Biology Lab 6: Molecular Biology

Paul Andersen explains the two major portions of the molecular biology lab in AP Biology. He starts by discussing the process of transformation. He explains how you can use the pGLO plasmid to produce glowing E. coli bacteria. He then describes how you can use restriction enzymes and the process of gel electrophoresis to cut and separate DNA.

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