genes part 2

• Genetics


  Study of genes and their transmission from one generation to the next. How parents pass their traits to the offspring.
• Genes


  DNA sequence that contain instructions for building proteins. Is a segment in the DNA sequence.
• 1 Gene = 1 Trait
• Genome


  Sum total of all an organism's DNA.
• Gregor Mendel


  • Father of Modern Genetics
  • Conducted experiments on Garden Peas
  • Was a Monk, which was against the church at the time
  • Was the son of a farmer
  • His works were burned
• DNA


  Backbone or the blueprint.
• Genome


  Complete genetic material of an organism along with its non-coding nucleic acid sequence. Regardless if it's coding or noncoding.
• Chromosomes


  A cellular structure consisting of one DNA molecule and associated protein molecules.
• Genes


  Discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA (or RNA, in some viruses). Segment in our DNA.

  
• Genotype


  The genetic bases of the Phenotype. Determines what Phenotype will be expressed.

  
• Phenotype


  Physical Traits. The traits that are being manifested in the human being. The traits that we see physically.
• There are Phenotypes that are not pure, they are Heterozygous - not 100% for a specific Phenotype.

  
• Variance


  Because of the differing genotype. Because in every Phenotype, we are not 100% sure if it's pure or a mixture of different phenotype with dominance.
• Humans have 46 CHROMOSOMES - 23 Pairs, 1 Autosomes (Body Cells), 1 Allosome (Sex Chromosomes) - XX = Female, XY = Male

  
• Karyotype


  Composite visual display of all the chromosomes of an individual. Shows all 23 pairs of chromosomes lined up side-by-side. Used to identify size, shape, and total number of chromosomes, as well as abnormalities.

  
• Types of Chromosomal Mutation

  • Structural Mutation - Structure of the Chromosomes are affected
  • Numerical Mutation - Number of Chromosomes are affected

  
• Homologous Chromosomes pair up during Meiosis because they are the same size, have the same centromere location, same shape, and code for the same genes.
• Gene Locus (Loci)


  Location of a specific pair of genes.
• Alleles


  Alternative versions of the same gene pair.
• Dominant


  Masks or suppresses the expression of its complementary allele. Always expressed, even if Heterozygous. Represented by a capital letter.

  
• Recessive


  Will not be expressed if paired with a dominant allele (Heterozygous). Will only be expressed if individual is homozygous for the recessive allele. Represented by a small letter.

  
• Homozygous


  Two identical alleles in a particular locus.
• Heterozygous


  Two different alleles at a particular locus. Combination of a dominant and recessive gene.

  
• Genotype


  The genetic code. Important to know the genotype to have probabilities.

  
• Phenotype


  The physical traits. Depends upon the Genotype but can also be influenced by environmental factors.
• Mendel


  • Austrian monk who discovered the basic principles of heredity through an experiment in Peas Garden
  • His observations became the foundation of modern genetics
  • Pioneer in the field of Genetics
• Mendel's Laws of Inheritance


  • Law of Segregation
  • Law of Independent Assortment
  • Law of Dominance
• Inheritance


  The process as to how an offspring received information from the parents.
• Law of Dominance


  Hybrid offspring will only inherit the dominant trait in the Phenotype. Suppressed trait is called Recessive, expressed trait is called Dominant. Heterozygous Alleles will always be DOMINANT.

  
• Law of Segregation


  During the production of gametes, two copies of each hereditary factor segregate so that offspring acquire one factor from each parent.
• Law of Independent Assortment

  A pair of traits segregates independently of another pair during gamete formation.
• Both traits will not be passed from parents to offspring together. They behave independently.
• Punnet Square


  A diagram used to predict the outcome of a particular cross breeding experiment. Not 100% accurate, named after Reginald C. Punnet, used by biologists to determine the probability of an offspring having a particular genotype.

  
• Types of Punnet Square


  • Monohybrid Cross - Crossing only one trait per parent
  • Dihybrid Cross - Crossing two different traits
• Law of Independent Assortment


  Has something to do with Law of Segregation. A pair of traits segregates independently of another pair during gamete formation.
• What traits will be dominant, what traits will be not

  
• Different traits have an opportunity to occur together
• All alleles will be given a chance to be expressed
• Dihybrid Cross


  Combination of two different genes. 2 different gene. Normally seen in F2
• Punnet Square


  A diagram that is used to predict an outcome of an particular cross breeding experiment