GEN 3000 Exam 1 2016 Study Guide Dr Tsai Clemson University Exam 1 Chapters 1 4 Modeled around Dr Tsai s recommended subjects to study color coded organized by chapter Chapter 1 Introduction to Genetics 1 Heredity is the basis of genetics regardless of what definition you look at 2 Types of Genetics We will be looking at Transmission Genetics Mendel s work peas generational genetics Genetic information passed from one generation to the next Molecular Genetics The fine details within the big picture The why and how Involves DNA Replication transcription translation RNA protein creation This process is the central idea Population Genetics Genetics on a broader scale that spans multiple generations of a population This is especially relevant in the work of Darwin and theories of evolution 3 Model organisms and their importance E coli used to study colon cancer and other cancers S Cerevisiae used to study cancer and Werner Syndrome Model Organisms Used in Genetic Studies It is important to see that there are a multitude of organisms than can and do get used for studies of human diseases and disorders without using actual human subjects The following are some of the common ones which we discussed in class D melanogaster used to study disorders of the nervous system as well as cancer D rerio used to study cardiovascular disease M musculus used to study Lesch Nyhan disease cystic fibrosis fragile X syndrome among others Canis lupus familaris Aka the dog used to study genetics in general C elegans used to study diabetes 4 The early theories of heredity and transmission Pangenesis The early idea that specific particles called gemmules carried information from all over the body to reproductive organs to be passed to the embryo at conception At this time sperm and egg hadn t been visualized but the concept of gemmules was similar to gametes The term gene did however come from this early theory This idea led to the idea of inheritance of acquired characteristics Inheritance of Acquired Characteristics The idea that learned skills and trades could be passed onto offspring Later found that they could not only genotypic information can be passed on Preformation The idea that inside egg or sperm is a tiny version of an adult this tiny person was called a homunculus Fertilization allows it to grow and develop Originally the homunculus was thought to be in the sperm then maybe in the egg Then the idea of blending inheritance was born Blending Inheritance The idea that offspring are a blend of both parents and contain traits from each 5 Influential People in the History of Genetics and their Major Contributions Robert Hooke Invented and used the early microscope to discover the cell This allowed for the visualization of gametes which led to the concept of Preformationism see above Schleiden and Schwann Developed the cell theory the idea that cells are the basic unit of all living things and they divide and arise from preexisting cells even on the single cellular level Helped to push the idea that there is no such thing as a sudden appearance of an organism Darwin Developed the theory of evolution through natural selection His published work was On the Origin of Species Established that heredity is the fundamental of evolution and created the idea that evolution and natural selection are based on the passing of genes Gregor Mendel Worked around same time as Darwin Discovered basic principles of heredity using pea plants and the analysis of their patterns of transmission in the mid 1800 s However this work went largely ignored until the 1900s Walter Flemming Observed the division of chromosomes Then it was discovered in 1885 that hereditary information is contained in the nucleus August Weismann The idea of inheritance of acquired characteristics was hard put to die out So Weismann experimented by cutting off the tails of mice for 22 generations This showed that tail length did not change in subsequent generations The germ plasm theory was then developed which suggested cells of the reproductive system carry complete sets of information The idea that the sperm and egg carry preexisting information Sutton Credited with developing the Chromosomal Theory of Inheritance or the idea that the genetic material in living organisms is contained in chromosomes Chapter 2 Mitosis and Meiosis 1 Prokaryotes versus Eukaryotes and viruses There are 3 major groups of life eubacteria archaea eukaryotes Eu true Pro pre Karyote nucleus All organisms have different numbers of base pair genomes but that number doesn t necessarily denote complexity Prokaryote Has a cell wall and a plasma membrane contains ribosomes and DNA Tend to be small and less complex Contain no membrane bound nucleus or organelles It includes the classifications of eubacterium and the archaebacterium Archaebacterium contain characteristics of bacteria and eukaryotes Eubacteria true bacteria Generally reproduce asexually through binary fission o Reproduction Contains a single circular chromosome attached to the plasma membrane The chromosome begins to replicate and the plasma membrane grows causing two chromosomes to separate followed by separation of organism into two individual cells Each cell is identical Eukaryotes Tend to be relatively large and complex with multiple linear DNA molecules Contain membrane bound organelles nucleus and a cytoskeleton Includes fungi and larger multi cellular organisms Usually reproduce sexually o Reproduction Eukaryotes typically have 2 sets of chromosomes per cell as a result of sexual reproduction One set from mother one from father called homologous pairs Viruses are NOT cells They contain a viral protein coat and a core of genetic information They can only reproduce inside of a host cell and it has been discovered that most viruses are closely related according to genetic sequence evolutionarily to their host 2 Ploidy In sexual reproduction of eukaryotes If there are 2 sets of genetic information a cell is diploid 2n most eukaryotic cells Most cells are diploid in eukaryotic organisms If a cell has only 1 set of genetic information it is haploid 1n reproductive cells Only reproductive cells are haploid 3 Chromosomes and their Structure Centromere Can be located anywhere along the chromosome length It is incredibly important because without it you can lose that chromosome It is a landing spot for the kinetochore that will form and be instrumental in the movement of chromosomes We also use the centromere to count