Answer:
SSYy
Step-by-step explanation:
This question involves two genes coding for two distinct traits in a flowering plant. According to the question, straight leaf is dominant to curly leaf in the first gene while yellow flower is dominant to red flower in the second gene.
Let us assume that:
In the first gene coding for leaf structure, S is the allele for straightness while s is the allele for curliness. This means that 'S' is the dominant allele while 's' is the recessive allele.
In the second gene coding for flower colour, Y is the allele for yellow while y is the allele for red. This means that 'Y' is the dominant allele while 'y' is the recessive allele.
According to the question, the flowering plant possesses a homozygous straight leaf. This means that it contains the same alleles for the dominant trait (straight leaf) in the first gene i.e. SS
The same flowering plant also has an heterozygous yellow flower. This means that, in the second gene, it contains a combination of the dominant (yellow) and the recessive (red) allele i.e. Yy but it will be phenotypically yellow because the yellow allele (dominant) will mask the expression of red allele (recessive).
In a nutshell, a flowering plant that possesses an homozygous straight leaf and heterozygous yellow flower will have a genotype that looks like: SSYy