inheritance

• What is the definition of genotype?

  Genetic constitution of an organism
• How is phenotype defined in the context of genetics?

  Expression of genes and environmental interaction
• What does homozygous mean?

  Two identical alleles for a gene
• What does heterozygous mean?

  Two different alleles for the same gene
• When are recessive alleles expressed?

  Only if no dominant alleles are present
• What is the definition of dominant alleles?

  Always expressed in the phenotype
• What is monohybrid inheritance?

  Inheritance of one gene at a time
• What is dihybrid inheritance?

  Inheritance of two genes at the same time
• What are the five different types of inheritance?

  • Dominance
  • Multiple alleles
  • Sex linkage
  • Autosomal linkage
  • Epistasis
• What does dominance in genetics refer to?

  Both dominant alleles expressed in phenotype
• What are multiple alleles?

  More than two options for a single gene
• What is sex linkage in genetics?

  Gene located on the X chromosome
• What is autosomal linkage?

  Genes located on the same non-sex chromosome
• What is epistasis?

  One gene modifies the expression of another
• What is the coding for monohybrid inheritance?

  One letter for the gene, capital and lowercase
• How is codominance represented in genetic coding?

  Base letter with superscript for alleles
• What are the four blood group phenotypes?

  A, B, AB, and O
• What is the relationship between blood group A and its alleles?

  A is dominant, O is recessive
• What is the probability of offspring having blood group A from AB and O parents?

  50% probability of blood group A
• What is the probability of children being colorblind from a carrier female and non-colorblind male?

  25% probability of colorblind child
• How can you determine which type of inheritance to use?

  • Count the number of phenotypes:
  • Two: Monohybrid
  • More than two: Codominance or multiple alleles
  • Check if it's specified as sex-linked
• What is a dominant allele?

  An allele that is always expressed
• What are recessive alleles?

  Alleles expressed only without a dominant allele
• What does genotype refer to?

  The genetic composition of an organism
• What is phenotype?

  The characteristic due to genotype and environment
• What is a gene?

  A small section of DNA coding for a polypeptide
• What are alleles?

  Alternative forms of one gene
• What is a dihybrid cross?

  Inheritance of two genes in one Punnett square
• What is the first step in a genetic cross?

  Label the parent phenotypes
• What does homozygous mean?

  Having two identical alleles for a gene
• What gametes can the round yellow pea produce?

  Capital R and capital Y
• What gametes can the wrinkled green pea produce?

  Lowercase r and lowercase y
• What is the offspring genotype from the cross of a homozygous dominant and a homozygous recessive parent?

  All offspring will be heterozygous
• What does F1 represent in genetics?

  The first generation of offspring
• What is the ratio of phenotypes in a dihybrid cross of two heterozygous parents?

  9:3:3:1 ratio
• What is autosomal linkage?

  Two genes located on the same chromosome
• What is the impact of crossing over in meiosis?

  Creates new combinations of alleles in gametes
• What happens to the expected ratio if crossing over occurs?

  The ratio may differ from the expected
• What is the expected phenotype ratio in autosomal linkage?

  3:1 ratio
• Why do yellow and round phenotypes appear more frequently?

  They are the result of original linked genes