Mitosis

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.
Read More

Blood Types

Paul Andersen explains the importance of blood types in blood transfusions. He starts with a brief discussion of blood antigens and antibodies. He describes how the ABO differs from the Rh blood type. He shows you how to solve simple genetic problems using Punnett squares. He then talks about the percentage distribution of the different types and the problems that may result during pregnancy.
Read More

Unit 5 Review - Genetics

Paul Andersen reviews the major concepts within the fifth unit of the new AP Biology framework. He starts with a description of both DNA and DNA. He explains how DNA is copied during the S phase of mitosis. He explains how transcription produces a strand of mRNA that is translated at the ribosome into a polypeptide. He compares and contrasts mitosis and meiosis and differentiates between haploid and diploid cells. He finally discusses Mendelian and chromosomal genetics. He finishes the podcast with a discussing of operons and transcription factors.
Read More

053 - Genotype Expression

Paul Andersen explains how genotypes can be expressed or not based on changes in the environment. He starts with a brief description of the Himalayan rabbit and how melanin production can be disrupted by high temperature. He explains how this could be advantageous in both the arctic fox and hare. He explains how flowers can vary temperature based on the pH of the soil. He finally describes gene expression in Lac+ bacteria.
Read More

034 - Mechanisms that Increase Genetic Variability

Paul Andersen describes mechanisms that increase the genetic variation within a population. He begins by discussing how horizontal transfer can move genetic material between bacteria. Transformation, transduction, and conjugation in bacteria are all included. He also explains how crossing over, random assortment, and random fertilization can maintain genetic variation in eukaryotes. He also explains how inbreeding can decrease the fitness of an individual.
Read More

032 - Signal Transmission and Gene Expression

Paul Andersen explains how signal transmission is used to alter both cellular function and gene expression. He uses the example of epinephrine release in humans and how it is used in the fight or flight response. Epinephrine causes liver cells to release glucose that is normally stored as glycogen when they receive the signal of epinephrine. They are also able to create different enzymes when receiving this signal. The signal transduction pathway and the importance of CyclicAMP is included.
Read More

030 - Advanced Genetics

Paul Andersen explains important concepts that can not be explained by simple Mendelian genetics. He begins with a discussion of polygenic inheritance and uses a simulation on height to show how a bell shape curve of phenotypes is produced. He then discusses the importance of linked genes and those that are found on the sex chromosome. A simple punnett square showing the inheritance of the color blind gene is included.
Read More

029 - Mendelian Genetics

Paul Andersen explains simple Mendelian genetics. He begins with a brief introduction of Gregor Mendel and his laws of segregation and independent assortment. He then presents a number of simple genetics problems along with their answers. He also explains how advances in genetic knowledge may lead to ethical and privacy concerns.

 

Read More

027 - DNA and RNA - part 2

Paul Andersen continues his description of DNA and RNA. He begins with the structure of DNA and RNA and moves into the process of DNA Replication. He also describes the central dogma of biology explaining how DNA is transcribed to mRNA and is finally translated into proteins. He also introduces genetic engineering and explains how transformation is used to create insulin.
Read More

024 - Development: Timing and Coordination

Regulation of Timing and Coordination in Development - Paul Andersen explains how genes control the timing and coordination of embryo development. Seed germination initiates the discussion of cell differentiation. The SRY gene and genetic transplantation shows the importance of embryonic discussion. Cell deat is also an important part of development that is regulated by microRNA. HOX genes (a form of homeotic genes) is also discussed.
Read More