Presentation on theme: "Modern Genetics Human Inheritance Human Genetic Disorders Advances in Genetics Table of Contents."— Presentation transcript:
Modern Genetics Human Inheritance Human Genetic Disorders Advances in Genetics Table of Contents
Modern Genetics Patterns of Human Inheritance 1.Single genes with two alleles Ex: widow’s pick Figure 2 Punnett Square
Modern Genetics - Human Inheritance Patterns of Human Inheritance Single genes with multiple alleles Ex: Inheritance of Blood Type Blood type is determined by a single gene with three alleles.fig3/146
Modern Genetics Patterns of Human Inheritance Traits controlled by many genes Ex: human height Discovery activity/p144
Modern Genetics - Human Inheritance The Sex Chromosomes The sex chromosomes carry genes that determine whether a person is male or female. They also carry genes that determine other traits.
Modern Genetics The Sex chromosomes Sex-linked genes- genes on the X and Y chromosomes not always the same Can have dominant and recessive alleles Because males have only one X chromosome, male are more likely to have a sex linked trait that is controlled by recessive alleles. Female -2X Male 1X, 1Y
Modern Genetics - Human Inheritance Colorblindness Punnett Square Red-green colorblindness is a sex-linked trait. A girl who receives only one recessive allele (written X c ) for red-green colorblindness will not have the trait. However, a boy who receives one recessive allele will be colorblind.
Modern Genetics Main Idea Detail Identifying Main Ideas As you read the section “Patterns of Human Inheritance,” write the main idea in a graphic organizer. Then write three supporting details that further explain the main idea. Human traits are controlled by single genes with two alleles, single genes with multiple alleles, and multiple genes. Human traits controlled by single genes with two alleles have two distinctly different phenotypes. Though a single gene can have multiple alleles, a person can carry only two of these alleles. Multiple genes that control a trait act together to produce a single trait with a large number of phenotypes. - Human Inheritance
Modern Genetics The effect of environment Many of a person’s characteristics are determined by an interaction between genes and the environment
Modern Genetics Links on Genetics Click the SciLinks button for links on genetics. - Human Inheritance
Modern Genetics End of Section: Human Inheritance
Modern Genetics Human Genetic Disorders Genetic disorder- abnormal condition that a person inherits through genes or chromosomes Causes: Mutations in the DNA of genes Changes in the structure of chromosoms Changes in the number of chromosomes
Modern Genetics Human Genetic Disorders Cystic Fibrosis- body produces abnormally thick mucus in the lungs or intestines Cause by a recessive allele on one chromosome as a result of a mutation in which three bases are removed from a DNA molecule
Modern Genetics Human Genetic Disorders Sickle –Cell Disease Affects hemoglobin, a protein in the red blood cells that carries oxygen; cells clog blood vessels The allele is codominant with normal allele A person with two sickle cell alleles will have the disease
Modern Genetics Human Genetic Disorders Hemophilia Person’s blood clots very slowly or nor at all Caused by a recessive allele on the X chromosome Sex-linked disorder/occurs more in male than in females
Modern Genetics Human Genetic Disorders Down Syndrome A person’s cell have an extra copy of chromosome 21 ( 3 chromosomes) Occurs when chromosomes fail to separate properly during meiosis Effect: some degree of mental retardation; heart defects
Modern Genetics - Human Genetic Disorders A Pedigree A pedigree is a chart or “family tree” that tracks which members of a family have a particular trait.
Modern Genetics - Human Genetic Disorders A Hemophilia Pedigree The pedigree shows the inheritance of hemophilia, a sex- linked disorder in a family.
Modern Genetics Managing Genetic Disorders Karyotypes- picture of all the chromosomes in a cell Genetic counseling- understand the chances of having a child with a particular genetic disorder Dealing with genetic disorders
Modern Genetics Pedigree Activity Click the Active Art button to open a browser window and access Active Art about pedigrees. - Human Genetic Disorders
Modern Genetics Comparing and Contrasting As you read, compare and contrast the types of genetic disorders by completing a table like the one below. Cystic fibrosisBody produces abnormally thick mucus. Recessive allele due to removal of three DNA bases DisorderDescriptionCause Sickle-cell disease Red blood cells are sickle-shaped and have reduced ability to hold oxygen. Codominant allele HemophiliaBlood clots slowly or not at all. Recessive allele on X chromosome Down SyndromeMental retardation and heart defects An extra copy of chromosome 21 - Human Genetic Disorders
Modern Genetics Sickle-Cell Disease Click the Video button to watch a movie about sickle-cell disease. - Human Genetic Disorders
Modern Genetics End of Section: Human Genetic Disorders
Modern Genetics Advances in Genetics Selective Breeding: selecting organisms with desired traits to be parents of the next generation Inbreeding: crossing two individuals that have the similar Characteristics Hybridization: crossing two genetically different individuals; the offspring will have the best traits from both parents
Modern Genetics Changing Rice Production The graph shows how worldwide rice production changed between 1965 and New, hybrid varieties of rice plants are one factor that has affected the amount of rice produced. - Advances in Genetics
Modern Genetics Changing Rice Production Rice production increased. Reading Graphs: According to the graph, how did rice production change between 1965 and 2000? - Advances in Genetics
Modern Genetics Changing Rice Production 2 in 1965; 4 in 2000 Reading Graphs: How many metric tons of rice per hectare were produced in 1965? How many were produced in 2000? - Advances in Genetics
Modern Genetics Changing Rice Production 2 metric tons/hectare Calculating: Calculate the approximate difference between rice production in 1965 and Advances in Genetics
Modern Genetics Changing Rice Production Possible answer: fertilizers and improved harvesting methods Developing Hypotheses: What factors besides new varieties of plants might help account for the difference in rice production between 1965 and 2000? - Advances in Genetics
Modern Genetics Cloning Organism that have the exact genes as the organism from which it was produced Is cloning ethical?
Modern Genetics - Advances in Genetics Genetic Engineering Scientists use genetic engineering to create bacterial cells that produce important human proteins such as insulin.
Modern Genetics Asking Questions Before you read, preview the red headings. In a graphic organizer like the one below, ask a question for each heading. As you read, write answers to your questions. QuestionsAnswers What is selective breeding?Selective breeding is the process of selecting organisms with desired traits to be parents of the next generation. Why are organisms cloned?To produce offspring with desired traits What is genetic engineering?A process in which genes from one organism are transferred into the DNA of another organism What advance has helped us learn about human genetics? The Human Genome Project - Advances in Genetics
Modern Genetics Links on Genetic Engineering Click the SciLinks button for links on genetic engineering. - Advances in Genetics
Modern Genetics Selective Breeding Click the Video button to watch a movie about selective breeding. - Advances in Genetics
Modern Genetics End of Section: Advances in Genetics
Modern Genetics Human traits controlled by such as Graphic Organizer Multiple alleles Single genes Sex-linked genes Widow's peakHeight Many genes Blood typeColorblindness
Modern Genetics End of Section: Graphic Organizer