College

We appreciate your visit to A horticulturalist wants to produce geraniums with specific characteristics She knows that the trait of red flowers is governed by the allele tex R tex. This page offers clear insights and highlights the essential aspects of the topic. Our goal is to provide a helpful and engaging learning experience. Explore the content and find the answers you need!

A horticulturalist wants to produce geraniums with specific characteristics. She knows that the trait of red flowers is governed by the allele [tex]R[/tex] ([tex]RR[/tex] and [tex]Rr[/tex]), and the trait of white flowers is governed by the allele [tex]r[/tex] ([tex]rr[/tex]).

The horticulturalist plans to cross a geranium that is true-breeding for red flowers with a geranium that is true-breeding for white flowers. Which Punnett square best describes this cross?

A.
[tex]
\[
\begin{array}{|c|c|c|}
\hline
& R & r \\
\hline
R & RR & Rr \\
\hline
r & Rr & rr \\
\hline
\end{array}
\]
[/tex]

Answer :

To solve this problem, we'll explore the genetic cross between a true-breeding red-flowered geranium and a true-breeding white-flowered geranium.

Here’s how you break it down:

1. Understanding the Genotype:
- The trait for red flowers is governed by the dominant allele "R" (either "RR" or "Rr" results in red flowers).
- The trait for white flowers is governed by the recessive allele "r" (only "rr" results in white flowers).
- A true-breeding organism has two identical alleles for a trait. Therefore, the true-breeding red-flowered geranium must have the genotype "RR", and the true-breeding white-flowered geranium must have the genotype "rr".

2. Setting Up the Cross:
- We're crossing a red-flowered geranium ("RR") with a white-flowered geranium ("rr").
- Each parent contributes one allele to the offspring.

3. Constructing the Punnett Square:
- The red-flowered parent with genotype "RR" can only pass on the "R" allele.
- The white-flowered parent with genotype "rr" can only pass on the "r" allele.

4. Filling in the Punnett Square:
- Each cell within the Punnett square represents a possible genetic combination in the offspring.
- As the only possible combination from "R" (from "RR") and "r" (from "rr") is "Rr", all offspring will have the genotype "Rr".

Based on this cross, all offspring will have the genotype "Rr", which results in red flowers. The Punnett square will look like this:

| Parent 1\Parent 2 | R | R |
|-------------------|---|---|
| r | Rr| Rr|
| r | Rr| Rr|

All the offspring (represented in the table cells) will be "Rr," indicating that they will all display the red flower phenotype due to the presence of the dominant "R" allele.

Therefore, the best description for this cross is a Punnett square where all combinations are "Rr", indicating red flowers for all offspring.

Thanks for taking the time to read A horticulturalist wants to produce geraniums with specific characteristics She knows that the trait of red flowers is governed by the allele tex R tex. We hope the insights shared have been valuable and enhanced your understanding of the topic. Don�t hesitate to browse our website for more informative and engaging content!

Rewritten by : Barada