GEN 3000 Notes Set 1 01 08 2016 Dr Tsai Clemson University Chapters 1 and 2 Instructor Kate Tsai Mastering Homework Due every Tuesday may vary but this is the general idea usually have about a week to do the homework First one intro to mastering is due on Tuesday but will never count late Mastering will also shut you out after you finish an assignment until closer to the exam to use to study There is a tutor available for the course on Sundays and Thursdays Important terms are often the blanks in slides that have to be filled in Can ask questions on the link called Questions on blackboard Classmates and Dr Tsai might answer Genetics The experimental Science of Heredity The study of heredity and the variation of inherited characteristics the branch of biology that deals with heredity especially the mechanisms of hereditary transmission and the variation of inherited characteristics among similar or related organisms The study of the patterns of inheritance of specific traits relating to genes and genetic information also known as heredity Lecture 1 Continued 1 8 2016 Genetics Through History We re not really sure when humans started questioning the idea of WHY things happen Domestication principles of heredity was first demonstrated 10 12 000 years ago Artifical fertilization was seen 2880 years ago And Hindu writings 2000 years ago suggested avoiding spouses with undesireable traits considering they noticed a trend of heredity 8000 1000 BC domestication of animals began but there wasn t as much going on 1600s was when the majority of hypotheses and theories began to show up Then the 1800s Darwin and Mendel A couple of concepts took hold originally Pangenesis specific particles gemmules carry information from the body to reproduce organs which are passed to embryo at conception Needless to say this fell out of favor At this time sperm and egg hadn t been visualized The term gene did however come from this early theory This idea led to the idea of inheritance of acquired characteristics the idea also was that skills would be passed onto the next generation artist passes on artistic ability to children Robert Hooke in 1665 discovered a cell using a microscope The use and invetention of the microscope led to the idea of Preformationism inside egg or sperm is a tiny version of an adult homunculus Fertilization allows it to grow and develop Originally thought to be in the sperm then maybe in the egg Then the idea of blending inheritance was born suggesting that offspring are a blend of parents Schleiden and Schwann came up with the cell theory and proposed it in 1839 cells are the basic unit of all living things and they divide and arise from preexisting cells Even on the single cellular level it arises from another cell Never just a sudden appearance of an organism In the 1850 s Darwin published his work He lived from 1809 1882 Theory of evolution through natural selection On the Origin of Species 1856 heredity was the fundamental of evolution The idea that evolution and natural selection are based on the passing of genes However at this time people didn t understand what was happening on a single level let alone a population level devaluing his work at the time Gregor Mendel was working about the same time as Darwin 1822 1884 Discovered basic principles of heredity 1866 However this work went largely ignored until the 1900s He crossed pea plants and analyzed patters of transmission Walter Flemming observed the division of chromosomes 1879 Then it was discovered in 1885 that hereditary information contained in the nucleus August Weismann cut off the tails of mice for 22 generations which showed that the idea of tail length did not change Germ plasm theory cells of the reproductive system carry complete sets of information The idea that the sperm and egg carry all of the information What s already there It wasn t until the mid 1900s that we see a lot of progression in the idea of genetics which is when we realize that Mendel s work is correct We went from the beginning of 1900s showing that genes are on chromosomes to 2003 the human genome project is complete Not going to be asked specific dates but will be asked for people and their specific goal Chapter 2 Chromosomes and Cellular Reproduction Mitosis Meiosis Prokaryote Has a cell wall and a plasma membrane contains ribosomes and DNA Tend to be small and less complex Contain no nucleus It includes the eubacterium and the archaebacterium Archaebacterium contain characteristics of bacteria and eukaryotes Eubacteria true bacteria Eukaryotes Has a nucleus relativelyu large and complex with multiple linear DNA molecules Contain membrane bound organelles and a cytoskeleton 3 major groups of life eubacteria true bacteria archaea eukaryotes Eu true Pro pre Karyote nucleus E Coli 4 7 Million base pairs of genomes Trypanosoma brucei 27 Million base pairs Human 3 4 Billion base pairs Tiger Salamander 31 Billion base pairs Marbled Lungfish 13 Billion base pairs Gonganlax polyedra 98 billion base pairs T Rex 1 9 Billion Base Pairs The microscope opened our eyes to the world of cell physiology Developed and used by Zacharias Janssen Robert Hooke and Antoni van Leeuwenhoek Began to differentiate microorganisms and began to be able to tell the difference between eukaryotic and prokaryotic cells The nucleus is very important because that s where genetic information is stored mitosis and meiosis Mitochondrion the powerhouse of the cell and contains genetic information and chloroplasts in plants also have genetic information Ribosomes are very important in the process off hereditation Bacterial DNA is somewhat sporadic and spread out Chromosome of Eukaryotes the result of DNA complexed to proteins The most compact DNA will ever be during cellular division During the majority of the cell cycle it will be called chromatin This is different than prokaryotes Eukaryotes have histone proteins that keep them bound 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 most are closely related according to genetic sequence evolutionarily to their host Cellular reproduction prokaryotes Contains a single circular chromosome attached ot the plasma membrane which replicates and the plasma membrane grows causing two chromoseds to separate and each cell is identical to eachother 1 bacteria divides every 20 minutes 10 billion bacteria in 10 hours Binary fission NOTE In genetics