By: Savannah Rodamer

 Alleles- alternative versions of a gene  Dominant Allele- determines the organisms appearance  Recessive Allele- has no noticeable effect on the organisms appearance  Law of segregation- two alleles for a heritable character segregate during gamete formation and end up in different gametes  Punnett square- diagrammatic device for predicting the allele composition of offspring from a cross between individuals of known genetic makeup  Homozygous- Organism that has a pair of identical alleles  Heterozygous- Organism that has two different alleles for a gene  Phenotype- Organisms appearance/physical traits  Genotype- Organisms genetic makeup  Monohybrids- individuals heterozygous for one character  Dihybrids- individuals heterozygous for two characters (YyRr)  Law of Independent assortment- each pair alleles segregates independently of each other pair of alleles during gamete function

 Test Crossing was first introduced by Gregor Mendel  It is used to determine if a group that has a dominant trait is homozygous or heterozygous for that particular trait  Test crosses determine the genotype of an individual with a dominant phenotype  The genotype of an offspring is determined by the allele inherited from its parents  There is a monohybrid cross and a dihybrid cross

 Basic principle of genetics and occurs in meiosis  Alleles for different traits separate when gametes are formed without influencing inheritance  At fertilization, the alleles randomly unite Mendel first used pea plants to show the law of independent assortment. Using a green pod that produced yellow seeds and a yellow pod that produced green seeds to represent a dihybrid cross

 If a tall tomato plant has the dominant allele T and a dwarf tomato plant has the recessive allele t. Create a punnet square. T t T t TTTt tt

 What is a test cross used for?  A:To determine an individuals genotype  During gamete formation genes for different traits separate without influencing each other’s inheritance. This illustrates which Law?  A: Law of Independent Assortment

 DTl8 DTl8

  demo/Testcross/test_cross.htm demo/Testcross/test_cross.htm  ics/ss/independent-assortment.htm ics/ss/independent-assortment.htm  efmenlawia.htm efmenlawia.htm