CROSS A HETEROZYGOUS TALL PLANT WITH A HOMOZYGOUS TALL PLANT. WHAT PERCENTAGE WILL BE SHORT?

Question

• Step 1- Identify the Trait - Plant Height
• Step 2- Identify the Alleles and Genotypes
T-tall t- short = Tall ____= short
• Step 3- Identify the parent genotypes
Heterozygous tall Homozygous tall_
• Step 4 Punnet Square
• Step 5 Answer the question
% short plant

Answer 1

To solve the problem of crossing a heterozygous tall plant with a homozygous tall plant, we can follow the steps you've outlined:

Step 1: Identify the Trait

• Trait: Plant Height

Step 2: Identify the Alleles and Genotypes

• Alleles: T (tall) and t (short)
• Genotypes:
  • Tall (T): Can be either homozygous (TT) or heterozygous (Tt)
  • Short (t): Homozygous (tt)

Step 3: Identify the Parent Genotypes

• Heterozygous tall plant: Tt
• Homozygous tall plant: TT

Step 4: Punnett Square

We will set up a Punnett square to visualize the genetic cross between Tt (heterozygous) and TT (homozygous tall).

       T      T
      __________
   T |   TT   |   TT   |
      |________|________|
   t |   Tt   |   Tt   |
      |________|________|

Step 5: Analyze the Punnett Square

The resulting genotypes from the Punnett square are:

• 2 TT (tall)
• 2 Tt (tall)

Step 6: Answer the Question

Now, we calculate the percentages of each genotype:

• Total offspring = 4 (2 TT + 2 Tt)
• Tall plants = 4 (100%)
• Short plants = 0 (0%)

Conclusion

The percentage of short plants from this cross is 0%. All the offspring will be tall (either homozygous TT or heterozygous Tt).