Mark the incorrect option for monohybrid cross in plant snapdragon

Options

A. `F_(1)` does not resemble either of the parents
B. The genotypic & phenotpic ratio were different
C. The ratio of pink to white flower is 2 :1
D. The test cross does not produce red coloured flower

Answer

To determine the incorrect option for the monohybrid cross in the snapdragon plant, we can follow these steps:

### Step 1: Understand the Basics of Monohybrid Cross
A monohybrid cross involves a single trait that is controlled by two alleles. In snapdragons, flower color is often used as an example, with red (R) being dominant and white (r) being recessive.

**Hint:** Recall the definitions of dominant and recessive traits when considering the alleles involved.

### Step 2: Identify the Phenomenon of Incomplete Dominance
In snapdragons, the phenomenon of incomplete dominance occurs. This means that when a red flowered plant (RR) is crossed with a white flowered plant (rr), the offspring (F1 generation) exhibit an intermediate phenotype (pink flowers, Rr) rather than showing the dominant phenotype.

**Hint:** Think about what happens when two different traits are combined and how they express themselves in the offspring.

### Step 3: Analyze the F1 Generation
In the F1 generation, all plants will have the genotype Rr and will display the pink phenotype. This indicates that neither the red nor the white flower color is fully expressed.

**Hint:** Remember that in incomplete dominance, the heterozygous phenotype is a blend of the two parental phenotypes.

### Step 4: Consider the F2 Generation
When the F1 generation (Rr) is self-fertilized, the F2 generation will show a phenotypic ratio of 1 red: 2 pink: 1 white. The genotypic ratio will also be 1 RR: 2 Rr: 1 rr.

**Hint:** Use a Punnett square to visualize the offspring ratios from the F1 generation.

### Step 5: Evaluate the Given Statements
Now, we need to evaluate the statements provided in the question to find the incorrect one:
1. F1 is not like both parents (Correct)
2. Genotypic and phenotypic ratios are different (Incorrect)
3. The ratio of pink and white is 2:1 (Correct)
4. In a test cross, red color flower is not produced (Correct)

**Hint:** Compare the ratios of genotype and phenotype; they should match in this case.

### Step 6: Identify the Incorrect Option
The incorrect statement is that the genotypic and phenotypic ratios are different. In the case of incomplete dominance in snapdragons, both the genotypic and phenotypic ratios are the same (1:2:1).

**Hint:** Focus on the definitions of genotypic and phenotypic ratios and how they relate to the traits being studied.

### Final Answer
The incorrect option for the monohybrid cross in snapdragon is: **"Genotypic and phenotypic ratios are different."**