DNA 2- Key Terms

• What is the focus of today's video?

  Different genetic terms related to DNA
• What is an allele?

  A different version of the same gene
• What is the difference between dominant and recessive alleles?

  Dominant alleles are expressed over recessive ones
• What does homozygous mean?

  Having two identical alleles for a gene
• What does heterozygous mean?

  Having two different alleles for a gene
• What is a genotype?

  The entire collection of alleles an organism has
• What is a phenotype?

  The characteristics derived from an organism's genotype
• If a mouse is heterozygous for fur color with one allele for purple and one for green, what color will it be if purple is dominant?

  It will be purple
• What must be true for a mouse to be green?

  It must be homozygous recessive for green fur
• How does the expression of alleles work in a heterozygous mouse?

  Only the dominant allele is expressed
• How do the genotypes of the three mice differ?

  They have different alleles and genetic codes
• Why do the heterozygous and homozygous dominant mice have the same phenotype?

  Both express the dominant purple color
• What is the relationship between genotype and phenotype?

  Genotype determines the phenotype of an organism
• What are the key terms related to genes discussed in the video?

  • Allele
  • Dominant
  • Recessive
  • Homozygous
  • Heterozygous
  • Genotype
  • Phenotype
• What are the characteristics determined by genes?

  • Traits inherited from parents
  • Can be determined by single or multiple genes
  • Examples include fur color and height
• How do alleles relate to genes and proteins?

  • Alleles are different versions of a gene
  • Genes code for specific proteins
  • Multiple alleles can exist for the same gene