Lecture 1 – Mendelian Inheritance
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Transformations of Lamarckism Vienna Series in Theoretical Biology Gerd B
Transformations of Lamarckism Vienna Series in Theoretical Biology Gerd B. M ü ller, G ü nter P. Wagner, and Werner Callebaut, editors The Evolution of Cognition , edited by Cecilia Heyes and Ludwig Huber, 2000 Origination of Organismal Form: Beyond the Gene in Development and Evolutionary Biology , edited by Gerd B. M ü ller and Stuart A. Newman, 2003 Environment, Development, and Evolution: Toward a Synthesis , edited by Brian K. Hall, Roy D. Pearson, and Gerd B. M ü ller, 2004 Evolution of Communication Systems: A Comparative Approach , edited by D. Kimbrough Oller and Ulrike Griebel, 2004 Modularity: Understanding the Development and Evolution of Natural Complex Systems , edited by Werner Callebaut and Diego Rasskin-Gutman, 2005 Compositional Evolution: The Impact of Sex, Symbiosis, and Modularity on the Gradualist Framework of Evolution , by Richard A. Watson, 2006 Biological Emergences: Evolution by Natural Experiment , by Robert G. B. Reid, 2007 Modeling Biology: Structure, Behaviors, Evolution , edited by Manfred D. Laubichler and Gerd B. M ü ller, 2007 Evolution of Communicative Flexibility: Complexity, Creativity, and Adaptability in Human and Animal Communication , edited by Kimbrough D. Oller and Ulrike Griebel, 2008 Functions in Biological and Artifi cial Worlds: Comparative Philosophical Perspectives , edited by Ulrich Krohs and Peter Kroes, 2009 Cognitive Biology: Evolutionary and Developmental Perspectives on Mind, Brain, and Behavior , edited by Luca Tommasi, Mary A. Peterson, and Lynn Nadel, 2009 Innovation in Cultural Systems: Contributions from Evolutionary Anthropology , edited by Michael J. O ’ Brien and Stephen J. Shennan, 2010 The Major Transitions in Evolution Revisited , edited by Brett Calcott and Kim Sterelny, 2011 Transformations of Lamarckism: From Subtle Fluids to Molecular Biology , edited by Snait B. -
Basic Genetic Terms for Teachers
Student Name: Date: Class Period: Page | 1 Basic Genetic Terms Use the available reference resources to complete the table below. After finding out the definition of each word, rewrite the definition using your own words (middle column), and provide an example of how you may use the word (right column). Genetic Terms Definition in your own words An example Allele Different forms of a gene, which produce Different alleles produce different hair colors—brown, variations in a genetically inherited trait. blond, red, black, etc. Genes Genes are parts of DNA and carry hereditary Genes contain blue‐print for each individual for her or information passed from parents to children. his specific traits. Dominant version (allele) of a gene shows its Dominant When a child inherits dominant brown‐hair gene form specific trait even if only one parent passed (allele) from dad, the child will have brown hair. the gene to the child. When a child inherits recessive blue‐eye gene form Recessive Recessive gene shows its specific trait when (allele) from both mom and dad, the child will have blue both parents pass the gene to the child. eyes. Homozygous Two of the same form of a gene—one from Inheriting the same blue eye gene form from both mom and the other from dad. parents result in a homozygous gene. Heterozygous Two different forms of a gene—one from Inheriting different eye color gene forms from mom mom and the other from dad are different. and dad result in a heterozygous gene. Genotype Internal heredity information that contain Blue eye and brown eye have different genotypes—one genetic code. -
Lesson Plan Mendelian Inheritance
Dolan DNA Learning Center Mendelian Inheritance __________________________________________________________________________________________ Overview • Computer with internet access This 90 minute lesson (two class periods of 45 minutes) is an introduction to Mendel’s Laws of Inheritance for students in Lesson Structure grades 5 through 8. By studying inherited traits in humans such as tasting PTC paper and inherited traits in plants such as Pre-lab (45 minutes) – Day 1 maize, we can understand how traits are passed down through Teacher Prep generations. A discussion of dominant and recessive traits in humans will encourage students to further explore their • Become familiar with Lab Center inheritance as well as their family inheritance. http://www.dnalc.org/labcenter/mendeliangenetics/m endeliangenetics_d.html Learning Outcomes • Print and copy Background Reading from the Students will be able to: Student Lab Notebook on the Lab center. • discuss the contributions of Gregor Mendel and his • Print and copy Student Pre-lab Worksheets from experiments with the garden pea. the Student Lab Notebook on the Lab center. • review the structure of DNA and chromosomes. • Cut paper strips for Sentence Strips activity. • compare a dominant trait to a recessive trait. • Make sure computers with Internet access are • compare a homozygous trait to a heterozygous trait. available. • identify traits in themselves that are either dominant or recessive. Before class • use maize as a model organism to study Mendelian Students will receive the background reading to read for inheritance. homework the night before starting lab. They will write 2 to 3 • demonstrate Mendel’s Law of Dominance and Law questions they have about the background information. -
Basic Genetic Concepts & Terms
Basic Genetic Concepts & Terms 1 Genetics: what is it? t• Wha is genetics? – “Genetics is the study of heredity, the process in which a parent passes certain genes onto their children.” (http://www.nlm.nih.gov/medlineplus/ency/article/002048. htm) t• Wha does that mean? – Children inherit their biological parents’ genes that express specific traits, such as some physical characteristics, natural talents, and genetic disorders. 2 Word Match Activity Match the genetic terms to their corresponding parts of the illustration. • base pair • cell • chromosome • DNA (Deoxyribonucleic Acid) • double helix* • genes • nucleus Illustration Source: Talking Glossary of Genetic Terms http://www.genome.gov/ glossary/ 3 Word Match Activity • base pair • cell • chromosome • DNA (Deoxyribonucleic Acid) • double helix* • genes • nucleus Illustration Source: Talking Glossary of Genetic Terms http://www.genome.gov/ glossary/ 4 Genetic Concepts • H describes how some traits are passed from parents to their children. • The traits are expressed by g , which are small sections of DNA that are coded for specific traits. • Genes are found on ch . • Humans have two sets of (hint: a number) chromosomes—one set from each parent. 5 Genetic Concepts • Heredity describes how some traits are passed from parents to their children. • The traits are expressed by genes, which are small sections of DNA that are coded for specific traits. • Genes are found on chromosomes. • Humans have two sets of 23 chromosomes— one set from each parent. 6 Genetic Terms Use library resources to define the following words and write their definitions using your own words. – allele: – genes: – dominant : – recessive: – homozygous: – heterozygous: – genotype: – phenotype: – Mendelian Inheritance: 7 Mendelian Inheritance • The inherited traits are determined by genes that are passed from parents to children. -
OUTLINE 12 IV. Mendel's Work D. the Dihybrid Cross 1. Qualitative Results 2
OUTLINE 12 IV. Mendel's Work D. The dihybrid cross 1. qualitative results 2. quantitative results E. Summary of Mendel's Rules V. Probability Theory and Patterns of Inheritance A. Definitions B. Rules for probability 1. independent outcomes 2. the product rule 3. single event; multiple outcomes 4. the addition rule C. Application to the dihybrid cross VI. Extensions of Mendel’s Rules Fig 14.2 A monohybrid cross Fig 14.3 P Homozygous P P Heterozygous p P p P PP Pp p Pp pp Genotypes: PP, Pp, pp genotype ratio: 1:2:1 Phenotypes: Purple, white phenotype ratio: 3:1 Fig. 14.6 A Test Cross Table 14.1 Fig. 14.7 A Dihybrid Cross Mendel’s Laws (as he stated them) Law of unit factors “Inherited characters are controlled by discrete factors in pairs” Law of segregation “When gametes are formed, the factors segregate…and recombine in the next generation.” Law of dominance: “of the two factors controlling a trait, one may dominate the other.” Law of independent assortment: “one pair of factors can segregate from a second pair of factors.” When all outcomes of an event are equally likely, the probability that a particular outcome will occur is #ways to obtain that outcome / total # possible outcomes Examples: In a coin toss P[heads] - 1/2 (or 0.5) In tossing one die P[2] = 1/6 In tossing one die P[even #] = 3/6 Drawing a card P[Queen of spades] = 1/52 The “AND” rule Probability of observing event 1 AND event 2 = the product of their independent probabilities. -
INTRODUCTION to GENETICS Table of Contents Heredity, Historical
INTRODUCTION TO GENETICS Table of Contents Heredity, historical perspectives | The Monk and his peas | Principle of segregation Dihybrid Crosses | Mutations | Genetic Terms | Links Heredity, Historical Perspective | Back to Top For much of human history people were unaware of the scientific details of how babies were conceived and how heredity worked. Clearly they were conceived, and clearly there was some hereditary connection between parents and children, but the mechanisms were not readily apparent. The Greek philosophers had a variety of ideas: Theophrastus proposed that male flowers caused female flowers to ripen; Hippocrates speculated that "seeds" were produced by various body parts and transmitted to offspring at the time of conception, and Aristotle thought that male and female semen mixed at conception. Aeschylus, in 458 BC, proposed the male as the parent, with the female as a "nurse for the young life sown within her". During the 1700s, Dutch microscopist Anton van Leeuwenhoek (1632-1723) discovered "animalcules" in the sperm of humans and other animals. Some scientists speculated they saw a "little man" (homunculus) inside each sperm. These scientists formed a school of thought known as the "spermists". They contended the only contributions of the female to the next generation were the womb in which the homunculus grew, and prenatal influences of the womb. An opposing school of thought, the ovists, believed that the future human was in the egg, and that sperm merely stimulated the growth of the egg. Ovists thought women carried eggs containing boy and girl children, and that the gender of the offspring was determined well before conception. -
Patterns of Inheritance
Patterns of inheritance Learning goals By the end of this material you would have learnt about: How traits and characteristics are passed on from one generation to another The different patterns of inheritance Genomic or parental imprinting Observations of the way traits, or characteristics, are passed from one generation to the next in the form of identifiable phenotypes probably represent the oldest form of genetics. However, the scientific study of patterns of inheritance is conventionally said to have started with the work of the Austrian monk Gregor Mendel in the second half of the nineteenth century. In diploid organisms each body cell (or 'somatic cell') contains two copies of the genome. So each somatic cell contains two copies of each chromosome, and two copies of each gene. The exceptions to this rule are the sex chromosomes that determine sex in a given species. For example, in the XY system that is found in most mammals - including human beings - males have one X chromosome and one Y chromosome (XY) and females have two X chromosomes (XX). The paired chromosomes that are not involved in sex determination are called autosomes, to distinguish them from the sex chromosomes. Human beings have 46 chromosomes: 22 pairs of autosomes and one pair of sex chromosomes (X and Y). The different forms of a gene that are found at a specific point (or locus) along a given chromosome are known as alleles. Diploid organisms have two alleles for each autosomal gene - one inherited from the mother, one inherited from the father. Mendelian inheritance patterns Within a population, there may be a number of alleles for a given gene. -
Lecture No. IV
Course: Fundamentals of Genetics Class: - Ist Year, IInd Semester Lecture No. IV Title of topic: - Monohybrid crosses, Di-hybrid crosses, Test cross and Back cross Prepared by- Vinod Kumar, Assistant Professor, (PB & G) College of Agriculture, Powarkheda Monohybrid crosses:—Crosses between parents that differed in a single characteristic. The character (S) being studied in a monohybrid cross are governed by two or multiple variations for a single locus. The Mendel’s first law i.e. Law of segregation or purity of gametes can be explained by considering the monohybrid ratio i.e. by studying inheritance of only one character. For example: In pea, round seed shape is dominant over wrinkled seed shape. Generation Parental Parents Female X Male Phenotype Round X Wrinkled Genotype RR X rr Gametes R r Generation F1 Rr (Heterozygous) Round On selfing: Parents Female X Male Phenotype Round X round Genotype Rr X Rr Gametes R r R r Generation F2 ♂ R r ♀ RR Rr R Round Round r Rr rr Round Wrinkled Phenotype ratio: 3 round : 1 wrinkled Genotypic ratio: 1 RR : 2Rr : 1rr Two different alleles of the same gene i.e. ‘R’ and ‘r’ were brought together in the hybrid (F1). Even though the hybrid was round seeded in the next generation (F2) it produced both round and wrinkled seeded progeny. Thus both the alleles for round shape (R) and wrinkled shape (r) remained together in the hybrid without contaminating each other. In F2 generation (selfing of (F1) hybrid), the different phenotypes could be recovered because the two alleles in F1 remained pure and did not contaminate each other thus producing two types of gametes from F1 i.e. -
G14TBS Part II: Population Genetics
G14TBS Part II: Population Genetics Dr Richard Wilkinson Room C26, Mathematical Sciences Building Please email corrections and suggestions to [email protected] Spring 2015 2 Preliminaries These notes form part of the lecture notes for the mod- ule G14TBS. This section is on Population Genetics, and contains 14 lectures worth of material. During this section will be doing some problem-based learning, where the em- phasis is on you to work with your classmates to generate your own notes. I will be on hand at all times to answer questions and guide the discussions. Reading List: There are several good introductory books on population genetics, although I found their level of math- ematical sophistication either too low or too high for the purposes of this module. The following are the sources I used to put together these lecture notes: • Gillespie, J. H., Population genetics: a concise guide. John Hopkins University Press, Baltimore and Lon- don, 2004. • Hartl, D. L., A primer of population genetics, 2nd edition. Sinauer Associates, Inc., Publishers, 1988. • Ewens, W. J., Mathematical population genetics: (I) Theoretical Introduction. Springer, 2000. • Holsinger, K. E., Lecture notes in population genet- ics. University of Connecticut, 2001-2010. Available online at http://darwin.eeb.uconn.edu/eeb348/lecturenotes/notes.html. • Tavar´eS., Ancestral inference in population genetics. In: Lectures on Probability Theory and Statistics. Ecole d'Et´esde Probabilit´ede Saint-Flour XXXI { 2001. (Ed. Picard J.) Lecture Notes in Mathematics, Springer Verlag, 1837, 1-188, 2004. Available online at http://www.cmb.usc.edu/people/stavare/STpapers-pdf/T04.pdf Gillespie, Hartl and Holsinger are written for non-mathematicians and are easiest to follow. -
Mendelian Genetics the Laws of Inheritance Were Derived by Gregor Mendel, a 19Th Century Monk Conducting Hybridization Experiments in Garden Peas (Pisum Sativum)
Mendelian Genetics The laws of inheritance were derived by Gregor Mendel, a 19th century monk conducting hybridization experiments in garden peas (Pisum sativum). Between 1856 and 1863, he cultivated and tested some 29,000 pea plants. From these experiments he deduced two generalizations which later became known as Mendel's Laws of Heredity or Mendelian inheritance. Mendel's conclusions were largely ignored. • Gene – coding sequence of the DNA (it can be directly responsible for one trait or character). • Allele - an alternate form of a gene. Usually there are two alleles for every gene • Homozygous - when the two alleles are the same. • Heterozygous - when the two alleles are different, in such cases the dominant allele is expressed. • Dominant - a term applied to the trait (allele) that is expressed regardless of the second allele. • Recessive - a term applied to a trait that is only expressed when the second allele is the same • Phenotype - the physical expression of the allelic composition for the trait under study. • Genotype - the allelic composition of an organism. MENDEL’S 3 LAWS OF INHERITANCE • Law of Dominance (Uniformity): if two plants that differ in just one trait are crossed, then the resulting hybrids will be uniform in the chosen trait. Depending on the traits is the uniform feature either one of the parents' traits (a dominant-recessive pair of characteristics) or it is intermediate. MENDEL’S 3 LAWS OF INHERITANCE • Law of Segregation: It states that the individuals of the F2 generation are not uniform, but that the traits segregate. (The original traits did not “meld together”, they reappear.) Depending on a dominant-recessive crossing or an intermediate crossing are the resulting ratios 3:1 or 1:2:1. -
Tutorial: Mendelian Genetics
Mendelian Genetics Contents Introduction ........................................................................................................................ 1 Heredity Before Mendel ..................................................................................................... 2 Mendel and the Laws of Heredity....................................................................................... 4 The “Rediscovery” of Mendel ............................................................................................. 7 The Misuse of Mendel ........................................................................................................ 8 Mendel in the Modern World ........................................................................................... 10 References and Resources ................................................................................................ 10 Supplemental Material ..................................................................................................... 11 Introduction Today, when the word “genetics” is mentioned the mind is at once occupied with terms like cloning, PCR, the genome project, and genomics. Just a few decades ago, however, the word genetics conjured up a very different set of terms including crossing, segregation, Punnett square, and binomial expansion. It is not that these terms have disappeared or have been replaced since, it is, rather, that genetics moved full force into the molecular era in the late 1970s and, in the beginning of the twenty-first century, -
ZOOLOGY GENETICS Topic: Back Cross & Test Cross
ZOOLOGY GENETICS Topic: Back Cross & Test Cross Introduction The characteristics of the offspring of Mendel’s crosses can be predicted from the genotype of the parents through knowledge of dominant and recessive genes i.e., TT for tall and tt for dwarf traits. Mendel wanted to know whether the genotype of the individual be determined just from its phenotype. For recessive phenotype, it is possible, because it has only one genotype for example, tt for dwarf trait. But, the phenotypically dominant individuals show two types of genotypes – homozygous dominant (TT) and heterozygous dominant (Tt). In order to determine the genotypes of such phenotypes, Mendel employed two types of crosses viz., back cross and test cross. Without the knowledge of the genotype, just by crossing experiment, one can determine the genotype of the given phenotype with the help of these crosses. BACK CROSS Backcross is a cross of a hybrid (F1) with any one of its parents i.e. homozygous dominant or homozygous recessive parent. It is used in horticulture, animal breeding and in production of gene knockout organisms. These are performed in Monohybrid and Dihybrid crosses. 1. Monohybrid Back Cross:- In a monohybrid cross of homozygous tall (TT) and homozygous dwarf (tt) pea plants, the F1 progeny are heterozygous tall (Tt). When the F1 heterozygote (hybrid) is crossed either with its dominant parent or with its recessive parent, it is known as back cross and the results obtained from such a cross is as follows:- a. Back Cross with Homozygous Dominant Parent:- The F1 heterozygote (Tt) gives rise to two kinds of gametes viz., gametes with dominant factor for tall character (T) and gametes with recessive factor for dwarf character (t).