Chapter 15 - The chromosomal basis of inheritance. This chapter presents the following content: Mendelian inheritance has its physical basis in the behavior of chromosomes during sexual life cycles, morgan traced a gene to a specific chromosome, linked genes tend to be inherited together because they are located on the same chromosome,. | CHAPTER 15 THE CHROMOSOMAL BASIS OF INHERITANCE Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Section A: Relating Mendelism to Chromosomes 1. Mendelian inheritance has its physical basis in the behavior of chromosomes during sexual life cycles 2. Morgan traced a gene to a specific chromosome 3. Linked genes tend to be inherited together because they are located on the same chromosome 4. Independent assortment of chromosomes and crossing over produce genetic recombinants 5. Geneticists use recombination data to map a chromosome’s genetic loci It was not until 1900 that biology finally caught up with Gregor Mendel. Independently, Karl Correns, Erich von Tschermak, and Hugo de Vries all found that Mendel had explained the same results 35 years before. Still, resistance remained about Mendel’s laws of segregation and independent assortment until evidence had mounted that they had a physical basis in the behavior of chromosomes. Mendel’s hereditary factors are the genes located on chromosomes. Introduction Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Around 1900, cytologists and geneticists began to see parallels between the behavior of chromosomes and the behavior of Mendel’s factors. Chromosomes and genes are both present in pairs in diploid cells. Homologous chromosomes separate and alleles segregate during meiosis. Fertilization restores the paired condition for both chromosomes and genes. 1. Mendelian inheritance has its physical basis in the behavior of chromosomes during sexual life cycles Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Around 1902, Walter Sutton, Theodor Boveri, and others noted these parallels and a chromosome theory of inheritance began to take form. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Fig. Thomas Hunt Morgan was the first to associate a specific gene with a specific chromosome in the early 20th century. Like Mendel, . | CHAPTER 15 THE CHROMOSOMAL BASIS OF INHERITANCE Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Section A: Relating Mendelism to Chromosomes 1. Mendelian inheritance has its physical basis in the behavior of chromosomes during sexual life cycles 2. Morgan traced a gene to a specific chromosome 3. Linked genes tend to be inherited together because they are located on the same chromosome 4. Independent assortment of chromosomes and crossing over produce genetic recombinants 5. Geneticists use recombination data to map a chromosome’s genetic loci It was not until 1900 that biology finally caught up with Gregor Mendel. Independently, Karl Correns, Erich von Tschermak, and Hugo de Vries all found that Mendel had explained the same results 35 years before. Still, resistance remained about Mendel’s laws of segregation and independent assortment until evidence had mounted that they had a physical basis in the behavior of chromosomes. Mendel’s hereditary factors are
