1. Genetics 2.1 What is Genetics 2.1 What is Genetics 2.2 Inheritance 2.2 Inheritance 2.3 DNA 2.3 DNA 2.4 Mutations and Disease 2.4 Mutations and Disease 2.5 Genetic Technologies 2.5 Genetic Technologies

2. 2.1 What is Genetics Genetics is the science of inheritance Genetics is the science of inheritance Genetic information is carried on chromosomes in the nucleus of every cell Genetic information is carried on chromosomes in the nucleus of every cell chromosomes Chromosomes contain sequences of DNA called genes Chromosomes contain sequences of DNA called genesgenes Genes are the instructions for making proteins Genes are the instructions for making proteins proteins

3. 2.1 What is Genetics A chart depicting the chromosomes possessed by an individual is called a karyotype A chart depicting the chromosomes possessed by an individual is called a karyotype karyotype Gender is determined by the 23 rd pair of chromosomes called the sex chromosomes (XX or XY) Gender is determined by the 23 rd pair of chromosomes called the sex chromosomes (XX or XY) Gender Karyotypes are commonly made after amniocentesis Karyotypes are commonly made after amniocentesis amniocentesis

4. 2.1 What is Genetics Chromosomes must be replicated and distributed during cell division Chromosomes must be replicated and distributed during cell division Mitosis: the division of autosomal cells into two identical diploid daughter cells Mitosis: the division of autosomal cells into two identical diploid daughter cells Mitosis Meiosis: the division of sex cells to make four haploid gametes Meiosis: the division of sex cells to make four haploid gametes Meiosis

5. 2.1 What is Genetics Fertilization is the combining of two haploid gametes to make a diploid zygote Fertilization is the combining of two haploid gametes to make a diploid zygote Fertilization haploid gametes Fertilization haploid gametes By selectively breeding livestock and crops humans have altered naturally occurring species to suit our needs By selectively breeding livestock and crops humans have altered naturally occurring species to suit our needsselectively breedingneedsselectively breedingneeds

6. 2.2 Inheritance Gregor Mendel worked with pea plants to discover the basic rules of heredity Gregor Mendel worked with pea plants to discover the basic rules of heredity Gregor Mendel Gregor Mendel Every trait is controlled by two alternate forms of a gene called alleles Every trait is controlled by two alternate forms of a gene called alleles alleles One allele may be dominant while the other is recessive One allele may be dominant while the other is recessivedominant

7. 2.2 Inheritance A Punnett square can be used to determine the probable outcomes from a single trait cross A Punnett square can be used to determine the probable outcomes from a single trait crossPunnett squarePunnett square Important definitions: genotype, phenotype, heterozygous, homozygous Important definitions: genotype, phenotype, heterozygous, homozygous Human blood types illustrate other mechanisms of inheritance Human blood types illustrate other mechanisms of inheritanceblood typesblood types

8. 2.2 Inheritance Sex-linked inheritance involves alleles carried on the X chromosome (colour blindness and hemophilia Sex-linked inheritance involves alleles carried on the X chromosome (colour blindness and hemophiliacolour blindnesshemophiliacolour blindnesshemophilia

9. 2.3 DNA DNA: deoxyribonucleic acid DNA: deoxyribonucleic acid DNA DNA is a double helix consisting of paired nucleotides DNA is a double helix consisting of paired nucleotides paired nucleotides paired nucleotides The order of nucleotides determines the sequence of amino acids in a protein The order of nucleotides determines the sequence of amino acids in a proteinamino acidsamino acids DNA is self replicating using a semi- conservative process DNA is self replicating using a semi- conservative processself replicatingself replicating

10. 2.4 Mutations and Disease A mutation is a change is the sequences of bases in a DNA molecule A mutation is a change is the sequences of bases in a DNA moleculemutationDNA moleculemutationDNA molecule Mutations can be substitutions, additions or deletions Mutations can be substitutions, additions or deletions Mutations Addition and deletion mutations are called frameshift mutations Addition and deletion mutations are called frameshift mutationsframeshift

11. 2.4 Mutations and Disease Some mutations result in genetic disease Some mutations result in genetic diseasegenetic diseasegenetic disease If the mutation is recessive then it is possible for a person to be a carrier of the disease If the mutation is recessive then it is possible for a person to be a carrier of the disease The frequency of mutations are increased by mutagens The frequency of mutations are increased by mutagensmutagens Some mutagens are carcinogens Some mutagens are carcinogens

12. 2.4 Mutations and Disease A pedigree chart can be used to determine the type of inheritance of a genetic disease, to determine the genotypes of individuals and to identify carriers A pedigree chart can be used to determine the type of inheritance of a genetic disease, to determine the genotypes of individuals and to identify carrierspedigree chartpedigree chart Royal family pedigree chart Royal family pedigree chart Royal family Royal family

13. 2.5 Genetic Technology Genetic technologies include: Genetic technologies include: Transgenics: using recombinant DNA technology to modify the proteins produced by an organism (AKA genetic engineering or genetically modified organisms) Transgenics: using recombinant DNA technology to modify the proteins produced by an organism (AKA genetic engineering or genetically modified organisms) Transgenicsproteins Transgenicsproteins Gene therapy: replacing a defective gene to cure a disease Gene therapy: replacing a defective gene to cure a disease Gene therapy Gene therapy

14. 2.5 Genetic Technology DNA fingerprinting: cutting DNA into fragments and creating a unique profile for an individual DNA fingerprinting: cutting DNA into fragments and creating a unique profile for an individual DNA fingerprintingindividual DNA fingerprintingindividual