Heterozygous pea plant would have two kinds of gametes: T and t. Homozygous pea plant would have only one kind of gamete: T. Based on punnet square, all F1 progeny would be either TT or Tt for their genotype. T l tT TT l Tt T TT l Tt I have made punnet square for your easy comprehension. Since T is dominant over t, all F1 progeny will be tall, that is 100% tall in phenotype. 50% of this progeny would be homozygous tall and rest 50% would be heterozygous tall. Hope this helps.