Organisms and their Environment

• What does heterozygous mean?

  Two alleles are different
• What is the significance of gametes in genetics?

  • Gametes are formed randomly
  • They combine during fertilization
  • Contribute to genetic variation
• What allele represents short hair?

  H (dominant)
• What determines the phenotype when one dominant allele is present?

  It determines the phenotype
• What genotypes result in short hair?

  HH or Hh
• What genotype will have long hair?

  hh (homozygous recessive)
• What is the probability of obtaining homozygous dominant offspring (HH) from a Punnett square?

  25%
• What does a Punnett square show in genetics?

  • Predicts offspring genotypes
  • Displays allele combinations
  • Helps visualize genetic crosses
• What is the probability of obtaining homozygous recessive offspring (hh) from a Punnett square?

  25%
• What is the probability of obtaining heterozygous offspring (Hh) from a Punnett square?

  50%
• Can any result occur from the parents in genetics?

  Yes, results can vary
• What are the expected phenotypic ratios from the Punnett square results?

  • 75% short hair
  • 25% long hair