Question

Tall sunflowers are dominant to short, while yellow colored flowers are dominant to orange. Cross a plant thatis heterozygous for both traits with a plant that is homozygous dominant for height but heterozygous for flowercolor. The unit I’m on is (Dihybrid Crosses). I’m really confuse

Answer 1

In the dihybrid cross between a heterozygous (TtYy) and a homozygous dominant for height, heterozygous for flower color (TYy) plant, all offspring will be tall, with varying flower colors (yellow or orange) depending on the allele combinations.

Step-by-step explanation:

The question involves understanding dihybrid crosses and predicting offspring genotypes and phenotypes. Sunflowers exhibit two traits: height (tall or short) and flower color (yellow or orange). Tall height (T) and yellow flower color (Y) are dominant over short height (t) and orange flower color (y). You are asked to cross a plant that is heterozygous for both traits (TtYy) with a plant that is homozygous dominant for height (TT) but heterozygous for flower color (TYy).

To solve this, create a Punnett square with 16 squares to represent all possible allele combinations from the gametes of each parent. The tall plant's gametes will be TY and Ty. The heterozygous plant's gametes will be TY, Ty, tY, and ty. Fill in the Punnett square with these combinations to get the genotype of the potential offspring. Each genotype will code for a phenotype: tall or short sunflowers with either yellow or orange flowers.

In this dihybrid cross, all offspring will be tall due to the homozygous dominant allele for height. The flower color outcomes will be a mix of yellow and orange based on the TtYy and TYy alleles.

Answer 2

Traits of sunflowers

Tall plant: dominant (T)

Short plant: recessive (t)

Yellow-colored flowers: dominant (Y)

Orange-colored flowers: recessive (y)

P1 (heterozygous for both traits)

Tt Yy

P2 (homozygous dominant for height, heterozygous for color)

TT Yy

After the breed, we would have the following offspring:

What this means is that those inside blue (TtYy; 4 individuals (25 % of the offspring) and green (TTYy; 4 individuals (25 % of the offspring)) circles have the respective genotype of their parents, in other words, they inherited their very phenotypical traits, while there're other percentages of the offspring which could have traits of their both parents in its phenotype.