Biology 2 Essay

Biology 2 Essay Biology 2 Essay Biology 5B What are Mendel’s Concepts? 1. Alleles exist 2. Individuals can be homozygous or heterozygous 3. One allele is dominant over the other 4. Gametes are haploid A sperm or egg carries only one allele for each characteristic because homologous pairs separate during meiosis. Law of Segregation The inheritance of an allele for one characteristic does not effect the inheritance of an allele for a different characteristic Law of Independent Assortment How is sex determined in humans? Sex chromosomes, the man’s genes How many pairs chromosomes do humans have? 23 How many pairs of autosomes do humans have? 22 How many pairs of sex chromosomes do humans have? 1 a diagram used to show how a specific characteristic is passed through several generations in a family Pedigree a diagram used to show the possible gamete combinations from a genetic cross Punnett Square the mating of an organism possessing a dominant phenotype but unknown genotype with an organism possessing a recessive phenotype Test Cross Mendel’s factors; units of heredity; sections of DNA capable of causing a trait Gene the trait which, when in the presence of contrasting trait, expresses itself Dominant the trait which, when in the presence of the dominant, doesn’t express itself Recessive the physical expression of an organism’s genes Phenotype the genetic make-up of an individual organism Genotype the particular site on a chromosome where a particular gene is located Locus