DNA

• What is the focus of today's video?

  Different genetic terms and concepts
• What is the difference between dominant and recessive alleles?

  Dominant alleles are expressed over recessive ones
• What is an allele?

  A different version of the same gene
• What do homozygous and heterozygous mean?

  Homozygous means same alleles; heterozygous means different alleles
• What is a gene?

  A segment of DNA coding for a protein
• How do genes determine characteristics?

  They code for proteins that influence traits
• Can a single gene determine a trait?

  Yes, sometimes traits are determined by a single gene
• What trait is determined by multiple genes?

  Height
• What are alleles?

  Different forms of the same gene
• How many copies of each gene do we have?

  Two copies, one from each parent
• What does homozygous mean?

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

  Having two different alleles for a gene
• If a mouse is heterozygous for fur color, what does that mean?

  It has one allele for each color
• What happens when one allele is dominant over another?

  The dominant allele is expressed in the phenotype
• What is the phenotype of an organism?

  The observable characteristics from its genotype
• How can two mice have the same phenotype but different genotypes?

  They can have different alleles but express the same trait
• What is the genotype of a homozygous recessive mouse?

  Two alleles for green fur
• What is the genotype of a homozygous dominant mouse?

  Two alleles for purple fur
• What is the genotype of a heterozygous mouse?

  One allele for purple and one for green fur
• What are the key differences between genotype and phenotype?

  • Genotype: Collection of alleles
  • Phenotype: Observable characteristics
  • Different genotypes can result in the same phenotype
• What are the implications of dominant and recessive alleles in inheritance?

  • Dominant alleles are expressed in phenotype
  • Recessive alleles are only expressed when homozygous
  • Heterozygous individuals express the dominant trait
• What is the relationship between genes, alleles, and traits?

  • Genes code for proteins
  • Alleles are variations of genes
  • Traits are influenced by gene expression