Question

In a certain species of plant, red petals (R) are dominant to white (r). According to the Punnett Square, what is the probability of an offspring being white?

R

RRR

Rr

لا

Rr

r

(1 point)

0.25%

○ 50%

Ο 75%

Ο 100%

Answer 1

To determine the probability of an offspring being white (rr) in a species of plant where red petals (R) are dominant to white petals (r), we first need to analyze the genotypes shown in the Punnett Square.

Assuming the parents are:
- One parent with genotype Rr (heterozygous, red petals)
- Another parent with genotype Rr (also heterozygous, red petals)

The Punnett Square would look like this:

```
R r
-----------------
R | RR | Rr |
-----------------
r | Rr | rr |
-----------------
```

Now let's analyze the genotypes of the offspring:
- RR (homozygous dominant) = 1
- Rr (heterozygous) = 2
- rr (homozygous recessive) = 1

Total outcomes = 4:
- RR = 1
- Rr = 2
- rr = 1

The probability of offspring being white (rr) is:

\[
P(rr) = \frac{\text{Number of rr offspring}}{\text{Total number of offspring}} = \frac{1}{4} = 0.25
\]

To convert this into a percentage:

\[
0.25 \times 100 = 25\%
\]

None of the options given (0.25%, 50%, 75%, 100%) match our calculated probability.

If we reevaluate and assume the intended reference for "25%" was meant to be present but misphrased as "0.25%".

Thus, according to the options provided:

**The probability of an offspring being white is approximately 25%.**