1. Definition of a gene A piece of DNA that can be found on a specific location on a chromosome. Code for traits.

2. Genes & Alleles Different versions of a gene are called alleles. Gene/ allele

3. Alleles- Different forms of the same gene. This is an allele for blue eye color. This is an allele for brown eye color. Homologous chromosomes

4. Genes and alleles These are alleles of the same gene- eye color. Notice they are on the same location on the pair of homologous chromosomes.

5. What are homologous chromosomes? A pair of matching chromosomes in an organism, with one being inherited from each parent. Homologous chromosomes are the same size and structure. They carry the same genes in the same locations, however the gene pairs may be different versions from one another.

6. Homologous Pairs of Chromosomes w/different allele combinations Homozygous genes/alleles Heterozygous genes/alleles Homozygous genes/alleles

7. Homologous Pairs of Chromosomes One from dad and one from mom Gene location on the chromosome. Genes are found in pairs. A pair of alleles. Sometimes they are the same & sometimes they are different. Homologous chromosomes are similar but not necessarily identical. Each carries the same genes in the same order, but the alleles for each trait may not be the same. Three pairs of alleles. These code for the same version of the gene.

8. Human Karyotype A karyotype is the number, size, and shape of chromosomes in an organism.

9. GenotypePhenotypeKaryotype The genetic makeup of an organism. The specific visible characteristics of an organism. Entire chromosome pattern of an organism or species of organisms.

10. Homozygous vs heterozygous traits review Key Concepts: A homozygous trait is made up of two of the same alleles. Homozygous genotypes = HH, ii, bb, EE. A heterozygous trait is made of two different alleles. Heterozygous genotypes = Hh, Ii, Bb, Ee

11. Dominant vs Recessive Traits A dominant trait is one that shows up in the phenotype even though only one dominant allele is present in the genotype. Dominant genotypes are TT, Tt or RR, Rr. A recessive trait must have both of its alleles in order to show up in the phenotype. Examples include tt, rr, ee.

12. Dominant vs Recessive Examples Dominant- even with only one capital B. Recessive- is masked even if only one dominant allele is present

13. Punnett Squares and Probability Probability- the measure of the chance that the event will occur as a result of an experiment.