Question

A tall plant with red flowers is crossed with a dwarf plant with white flowers. Which one of the following represents dwarf plants with white flowers?
A. TrRr
B. TTrr
C. ttrr
D. ttRr

Answer 1

Hint: The systematic breeding of two separate individuals, resulting in offspring bearing part of each parent's genetic material. The parent organisms must be genetically identical and can come from different varieties or closely related species.

Complete answer: There are generally two types of traits- dominant and recessive. When the connected allele is dominant, dominant traits still appear, even though only one copy of the dominant trait (exists with one recessive trait). Recessive traits are only displayed if both the corresponding alleles are recessive. A genotype is the collection of heritable genes of an organism which can be transmitted from parents to offspring. The genes play a great role in the determination of traits, such as hair colour, height, etc., that are observed in an organism.
Tall is the dominant character in plants which is denoted by T and the dwarf is the recessive character which is denoted by t. The red flower is the dominant feature which is shown by R and white flower is the recessive character which is shown by r. So, the genotype of the tall plant with red flowers is TTRR or TtRr and the genotype of the dwarf plant with white flowers is ttrr.
So, the correct answer is “Option C”.

Note:
In between dominance and recessive, there is phenomena called codominance. In codominance (a heterozygous condition), under which the phenotype completely expresses all alleles at a gene locus. Alleles that display an independent effect are called Codominant alleles. Neither phenotype is completely dominant in codominance.