Paul Andersen explains the central dogma of biology. He explains how genes in the DNA are converted to mRNA through the process of transcription. He then explains how ribosomes use this message to convert the mRNA to a functioning protein. He also shows you how to decode a gene by converting the DNA to complementary mRNA and then to the specific amino acids in a protein.
Paul Andersen describes the process of mitosis. He begins by discussing the importance of the cell cycle in development, regeneration, asexual reproduction and wound healing. He differentiates between haploid and diploid cells and describes the structure of the chromosome. He then moves through all the phases of mitosis; interphase, prophase, metaphase, anaphase, telophase and cytokinesis.
Paul Andersen explains how the process of meiosis produces variable gametes. He starts with a brief discussion of haploid and diploid cells. He compares and contrasts spermatogenesis and oogenesis. He explains how each person is different due to independent assortment, crossing over and random fertilization.
Paul Andersen gives you a brief introduction to the cell membrane. He starts by describing amphipathic nature of a phospholipid and how it assembles into a membrane. He gives an overview of the fluid mosaic model inside cells. He also discusses the movement of material across a membrane and the role of proteins in movement and function.
Paul Andersen takes you on a tour of the cell. He starts by explaining the difference between prokaryotic and eukaryotic cells. He also explains why cells are small but not infinitely small. He also explains how the organelles work together in a similar fashion
Paul Andersen explains how variation is created within a cell. He starts by showing how molecular variation can increase fitness at the local level. He explains how an additional chlorophyll molecule allows plants to absorb more light from the sun. He also explains how cells can vary the composition of phospholipids in their cell membrane. He explains the significance of heterozygote advantage and how gene duplication can create novel genes. The antifreeze protein evolved from a simple digestive protein.
In this podcast Paul Andersen explains how cells differentiate to become tissue specific. He also explains the role of transcription factors in gene regulation. The location of a cell within the blastula ultimately determines its fate. The SrY gene is an important external stimuli in human development. The heat shock factor is also discussed as an example of an environmental simuli.
The lower half of Mr. Andersen's head explains why cells are small. This video begins with a simple geometry problem and ends with a discussion of Allen's Rule and reasoning for the microscopic nature of cells.
Paul Andersen describes the structure and function of the major organelles in a eukaryotic cell. The endoplasmic reticulum, ribosomes, and golgi complex produce and store proteins in the cell. Lysosomes dissolve broken and invasive material. Vacuole store material in plant cells. Mitochondria produce ATP through cellular respiration and chloroplasts use the energy of the sun to produce sugars.
Paul Andersen explains how the cell cycle is used to create new cells. The creation of identical diploid daughter cells, through mitosis, is described. The creation of unique haploid daughter cells, through meiosis is also described. The importance of cyclin and cyclin dependent kinases to regulate the cell cycle is included.
Paul Andersen explains how eukaryotic cells use compartmentalization to increase the surface area and level of specialization within the cell. Prokaryotic and eukaryotic cells are compared and contrasted. The role of both the mitochodria and endoplasmic reticulum are discussed.
Paul Andersen describes how cells move materials across the cell membrane. All movement can be classified as passive or active. Passive transport, like diffusion, requires no energy as particles move along their gradient. Active transport requires additional energy as particles move against their gradient. Specific examples, like GLUT and the Na/K pump are included.
Paul Andersen explains how cells are selectively permeable with the help of their cell membrane. The main constituents of the cell membrane, including cholesterol, glycolipids, glycoproteins, phospholipids, and proteins are included. The fluid mosaic model is also illustrated. The cell wall in plants, bacteria, and fungi is also discussed.
