# Flower color in snapdragons is due to a gene with incomplete dominance: CRCR plants have red flowers,

Flower color in snapdragons is due to a gene with incomplete dominance: CRCR plants have red flowers, CRCW have pink flowers, and CWCW plants have white flowers. What types and ratios of flower color are expected among the progeny of a cross of pink × white?
a.1 red:2 pink:1 white
b.1 red:1 pink
c.1 pink:1 white
d. all pink
e. all white

## This Post Has 3 Comments

1. calvinclifton says:

The question is incomplete. The complete question is:

Question: Flower color in snapdragons is due to a gene with incomplete dominance: CRCR plants have red flowers, CRCW have pink flowers, and CWCW plants have white flowers. Which cross is expected to yield progeny with flower colors in a ratio of 1 red:1 pink?

A. CRCR × CRCW

B. CRCR × CWCW

C. CRCW × CRCW

D. CRCW × CWCW

E. CWCW × CWCW

A. CRCR × CRCW

Explanation:

According to the given information, the flower color gene in snapdragon exhibits incomplete dominance. When a snapdragon plant with red flowers is crossed with a snapdragon plant with pink flowers, it obtains progeny in following phenotype ratio= 1 Red (CRCR): 1 Pink (CRCW).

Here, the genotype of the parent with the red flowers is CRCR and that of the parent plant with pink flowers is CRCW. The parent plant with pink flowers produces two types of gametes carrying CR or CW alleles.  Random fusion of gametes of the two parent plants obtains the progeny in 1 red: 1 pink ratio.

$Flower color in snapdragons is due to a gene with incomplete dominance: crcr plants have red flower$

2. litwork1726 says:

c.1 pink:1 white

Explanation:

Incomplete dominance is a genetic phenomenon whereby one allele of a gene is not completely dominant over the other allele, hence, it forms an heterozygous with an intermediate phenotype different from both parents. In this case of snapdragon plants, CRCR is the red allele while CWCW is the white allele. They form an intermediate phenotype that has pink flower colour; CRCW.

Hence, in a cross between a pink snapdragon (CRCW) and a white snapdragon (CWCW), four possible offsprings will be produced with two distinct genotypes: CRCW (2) and CWCW (2). Hence, this will give a ratio of 2:2 or 1:1 consisting of 1 pink : 1 white offspring.

3. joannegrace4898 says:

CRCR × CWCW

Explanation:

Flower color in snapdragons exhibits incomplete dominance wherein the heterozygous genotype exhibits the blend phenotype. To have all the pink-flowered progeny, all the progeny should have CRCW genotype and must obtain CR allele from one parent and CW from the other.

Among the given options, parent genotype "CRCR × CWCW" will give all the pink-flowered progeny. The parent plant with genotype CRCR would produce all the gametes with "CR" alleles while the parent with genotype "CWCW" would produce all the gametes with the "CW" allele. The random fusion of these gametes from the two parents would give all pink-flowered progeny with genotype "CRCW".

$Flower color in snapdragons is due to a gene with incomplete dominance: crcr plants have red flower$