ANTH 1102 Lecture 10 Outline of Last Lecture I. Scientific TerminologyII. 5 Key Themes of This Section of the BookIII. Recent Out-of-Africa theoryIV. Natural selection and genetic diversity among humans Outline of Current Lecture I. Genetics and Human Variationa. DNA, Genes, and Traitsi. DEFINITIONSII. DNA & Meiosisa. Two types of DNA do NOT mix/cross over Current LectureI. Genetics and Human Variationa. DNA, genes, and traitsi. 23 pairs of chromosomesii. Each chromosome is made of DNA iii. “gene”: short sequences of DNA that code for particular cellular actions or traits iv. DNA is a recipe; need interaction with the environment v. Expression: the expressed genes impact our phenotype, which is the physical trait that we seevi. Genotype: all of an organism’s genetic materialsvii. Phenotype: all of an organism’s observable traits (including things we cant“see” such as internal organs, behavior/mental traits)viii. Some genetic variation is not expressed (ex. Two brown eyed parents having a green eyed baby)ix. Mutation: occurs when mistakes are made while copying DNA during cell reproduction (sometimes as a result of environmental toxins/radiation)x. Meiosis: process by which sperm and egg cells are created (mutation can have an important roll in this)These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.1. These cells contain ½ of our chromosomes. 2. Mutation evident in meiosis produces new variationxi. Very difficult to directly trace ancestry/lineage II. DNA & Meiosisa. Two types of DNA do NOT mix/cross over during meiosis:i. 1. yDNA (y chromosome): If you are male, you inherit this chromosome only from your father.ii. 2. mtDNA (mitochondrial DNA): everyone inherits this only from our mothers- Mitochondria are small cellular structures (the “energy factory” of the cell) that have their own DNA. - In the absence of mixing, DNA mutations still occur, allowing us to trace human origins through ONLY mtDNA and