BIO Genetics Notes Chapter 1 PDF
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This document is a chapter on genetics, providing fundamental knowledge about DNA, genes, and proteins. It describes heredity, the role of genes in inheritance, and the structure, function, and importance of DNA sequences in organisms.
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BIO Genetics Notes Chapter 1 Vocab examples Genetics: The specific study of heredity- how traits and diseases are passed from generation to generation & cellular gene function - Influences social, political, legal, and ethical institutions and policies Gene: string of nucleotides in a DNA mole...
BIO Genetics Notes Chapter 1 Vocab examples Genetics: The specific study of heredity- how traits and diseases are passed from generation to generation & cellular gene function - Influences social, political, legal, and ethical institutions and policies Gene: string of nucleotides in a DNA molecule - The unit of heredity - The structural and functional unit of genetics - Genes made of unique sequences of nucleotides in a DNA molecule - 4 nucleotides - Adenine (A) - Thymine (T) - Guanine (G) - Cytosine © DNA sequence: - The sequence of the nucleotides in a DNA molecule - Stores the genetic information of an individual - Defines which aas will be used to make specific proteins Genes are sequences of nucleotides in DNA 3D structure of a protein - Aas are made of polypeptide chains, which become functional proteins when folded into specific 3D shapes upon activation - The action of proteins produce traits - Nucleotide sequence (the letters) encoded in a gene defines the AAs that make up the gene products (proteins) - When a gene gets activated its stored information is decoded to make a polypeptide which folds into a 3D shape turning it into a functional protein which then produces characteristics we can SEE or MEASURE Genes transmitted from parent to offspring - Mendel established the foundations of genetics Mendel’s Conclusions - Each parent carries 2 genes (gene pair) for a specific trait - Each parent contributes only one of those genes to its offspring - The 2 copies of a gene (from each parent) separate from each other during meiosis - @fertilization the genes from mom and dad become members of a new gene pair in the offspring Chromosomes: Genes contained on chromosomes in the nucleus of a eukaryotic cell The 4 ways scientists study genes - Transmission genetics: how genes are transferred from parent to next generation - Pattern of inheritance - EXAMPLE– mendel did transmission genetics using pea plants as his experimental organisms - Pedigree analysis: an indirect method to study the inheritance of humans by reconstructing the pattern of inheritance associated with a trait as it passes through generations to determine how a trait is inherited and to establish the risk of having affected children - Construction of family trees used to follow transmission (inheritance) of genetic traits in families - Males squares - Females circles - Shaded = affected - Each horizontal group is a new generation - Cytogenetics: using microscopy, genes and chromosomes are analyzed for arrangement and organization - Chrm number and structure - Maps genes and study chromosome structure and abnormalities in chrm number and organization - Karyotypes: standardized arrangements of chromosomes for diagnosing or ruling out genetic disorders - Each chrm is paired and arranged by size and shape - Molecular genetics: biochemical aspect - Recombinant DNA technology produces millions of clones of genes for study - Helps understand how genes are organized and function molecularly - Utilized in gene therapy: transfers human genes as treatment for genetic disorders - Ex: GMOS - Rec. DNA used in Human Genome Project to sequence the human genome: the complete set of genetic information an individual carries creating the new field of genomics – aka all 46 DNA molecules of 24 distinct types; the entire set of DNA instructions, as a whole - Genomics study the origin, function, and evolution of genes and their interactions - Population genetics: how much variation exists in a population and what alters the frequency of genes - The forces that change the frequency of genes in a population over many generations and its influence on evolution - Forces: migration, population size, and natural selection to change variation - Helps to understand the evolutionary history of our species and the migration patterns that distributed humans - Helped to develop: DNA fingerprinting and DNA identification used in paternity testing and forensics. Basic vs applied research - Basic research: figure out how something works or why it works the way it does - Goal is knowledge - Result: generate new ideas and more basic research - Example: in genetics→ learn about genes, how they work, and why they do not function properly - Applied research: to solve a problem or create a service or product - Goal: develop something or solve something - Example in genetics→ transmission genetics, biotech products (GMOs), new tests, make vaccines - Labs are working to move results of genetic research from the lab to clinical practice : translational medicine Impact of genetics on social policy and law - Eugenics: the attempt to improve the human species by selective breeding - Galton proposed that selection should be used to improve the human species - Rational was flawed bc he believed traits are inherited without environmental influence - Hereditarianism: all human traits (phenotypes) are handed down without environmental influence - Intellectual, economic, and social level of humankind could be improved by selective breeding through applying the principle of natural selection - Desirable traits should be encouraged to have families - Undesirable traits should be discouraged from reproducing - US - Laws restricted reproductive rights and required certain (genetic disorders and those convicted of certain crimes) individuals to be sterilized - Immigration laws after WWI restricted entry of populations deemed genetically inferior (Immigration Restriction Act of 1924) - Law changed in 1965 - EXAMPLE: Carrie Buck and 60K others in the US were sterilized for “appearing” genetically, intellectually, or morally “inferior” - Being “feebleminded and promiscuous” were genetic traits - Sterilization happened until 1979 in some states - Nazi Germany - Laws justifying genoside of individuals believed to ve genetically inferior were modeled on the sterilization laws and eugenics movement in the US - Eugenics movement was used as justification for the eradication of entire ethnic groups like the Jews The Impact of Genomics - Genes associated with 100s of genetic diseases have been cloned (recombant DNA technology) and are used to devolop genetic tests and therapies - EX: HGP - Single Nucleotide polymorphism : single nucleotide differences between and among individuals in a population/species - The simplest type of variation - The effects of SNPs on complex traits and disorders are being studied using genome wide association studies (GWASs) - Haplotype: a set of SNPs located close together on a single chromosome or chromosome region - Show differences of individuals at the molecular level - GWASs: analysis of genetic variation across an entire genome searching for associations between variations in DNA sequence and genome region encoding a specific phenotype (cancers, alzheimers, mental illness) - Genome screening using DNA microarrays/chips are used to assess genetic risk in families by screening the entire genome - The microarrays carry DNA from the entire human genome to determine genetic diseases or risk - Stem cells - In the embryo stem cells divide to form 200 different cell types that become part of tissues and organs - Regenerative medicine: ability to isolate stem cells from embryos and to produce stem cells from somatic cells (diploid, body cells) in the lab (aka induced pluripotent stem cells) to treat disorders - GMOs - More than 85% of corn and 95% of soybean are GMOs - More than 80% of processes foods in grocery stores are from transgenic plants