Genetic diagrams

• What do genetic diagrams show?

  Combinations of alleles from two parents
• What does the dominant allele 'A' code for in mice?

  Normal amounts of average muscle
• What does the recessive allele 'a' code for in mice?

  Muscular mass
• How are alleles represented in genetic diagrams?

  As uppercase and lowercase letters
• What does a homozygous normal mouse's genotype look like?

  Capital A, capital A
• What is the phenotype of a homozygous muscular mouse?

  Muscular
• How do you find the gametes from a parent's genotype?

  Split the letters into separate circles
• What do you do to find the offspring's genotypes?

  Combine the gametes from both parents
• What is the genotype of all offspring from a homozygous normal and a homozygous muscular mouse?

  All offspring are heterozygous
• What phenotype do all heterozygous offspring express?

  Normal phenotype
• What is a Punnett square used for?

  To show genetic combinations visually
• How is a Punnett square structured?

  A large square split into four smaller squares
• What is the ratio of normal to muscular mice from two heterozygous parents?

  3 to 1 ratio
• What is the probability of having muscular offspring from two heterozygous parents?

  One in four or 25%
• What is the outcome of a genetic diagram for two heterozygous mice?

  One homozygous dominant, two heterozygous, one homozygous recessive
• What environmental factors can affect traits like height?

  Food and sleep during childhood
• What is the importance of multiple genes in determining traits?

  They interact with each other and the environment
• What are the five main steps to draw a genetic diagram?

  1. Identify parents' phenotype and genotype
  2. Determine gametes' genotypes
  3. Combine gametes to find offspring's genotypes
  4. Determine offspring's phenotypes
  5. Present results in a diagram
• What are the strengths and weaknesses of genetic diagrams and Punnett squares?

  Strengths:

  • Genetic diagrams show allele combinations
  • Punnett squares are simpler to draw

  
  

  Weaknesses:

  • Genetic diagrams can be complex
  • Punnett squares don't show phenotypes
• The order of the genetic diagram

  
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  Punnett square structure- heterozygous

  
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  Punnett square- depth