Monohybrid And Dihybrid Crosses

9 Questions | Total Attempts: 2379

SettingsSettingsSettings
Please wait...
Monohybrid And Dihybrid Crosses

Show me that you understand how to predict the possible outcome of mono and dihybrid crosses using Punnett squares. Use the following letters for your crosses: T = tall t = short G = green seeds g = yellow seeds P = purple flowers p = white flowers


Questions and Answers
  • 1. 
    A purebred pea plant for height is crossed with a hybrid for height. The phenotypic ratio is 4:0.
    • A. 

      True

    • B. 

      False

  • 2. 
    Check all the possible combinations of alelles in this pea plant's pollen:    TtPp
    • A. 

      TP

    • B. 

      Tp

    • C. 

      TT

    • D. 

      Tp

    • E. 

      TP

    • F. 

      PP

  • 3. 
    A homozygous recessive plant has two copies of the ____________________ allele.
  • 4. 
    The ___________________ of the organism is what you can see.
  • 5. 
    The __________________________ of the organism is what is in the genes.
  • 6. 
    Perform the following cross and check the boxes for the correct phenotypic and genotypic ratios.
    • a heterozygous green seeded plant crossed with a purebred recessive for seed color
    • A. 

      Phenotypic ratio 2:2

    • B. 

      Genotypic ratio 2:2

    • C. 

      Phenotypic ratio 1:3

    • D. 

      Genotypic ratio 1:3

    • E. 

      Phenotypic ratio 1:2:1

    • F. 

      Genotypic ratio 1:2:1

  • 7. 
    In the following dihybrid cross there is no need to fill out the whole sixteen square table to determine the outcome.
    • TtGg  x  ttgg
    • A. 

      True

    • B. 

      False

  • 8. 
    When a purebred recessive plant is crossed with a plant with the dominant phenotype you can find out if the second plant is a hybrid or a purebred by looking at the possible offspring. Choose the correct allele combinations of the offspring if the unknown plant's genotype is homozygous dominant.
    • A. 

      All four of the offspring will have the dominant phenotype

    • B. 

      One will have the dominant phenotype and three will have the recessive

    • C. 

      Two will show the dominant phenotype and two the recessive

    • D. 

      One will have the recessive phenotype and three the dominant

Related Topics
Back to Top Back to top