Question

HELP ME PLEASE!!!
What percent of the offspring would have red flowers if you cross a heterozygous red flowered plant (Rr) with a heterozygous red flowered plant (Rr)? You must set up a punnett square and determine the genotypes before determing the phenotypes.


50% Red

75% Red

25% Red

100% Red

Answer 1

nooooo clue

Answer 2

poop

Answer 3

nooooo clue

Answer 4

For a flower to be heterozygous and red would mean that red color is the dominant trait. This means any flower with the genotype \(\mathrm{RR}\) or \(\mathrm{Rr}\) will be red.

A cross between two heterozygous flowers would give a genotypic ratio of \(1\,\mathrm{RR }:1\,\mathrm{Rr}:1\,\mathrm{rR}:1\,\mathrm{rr}\), or equivalently \(1\,\mathrm{RR}:2\,\mathrm{Rr}:1\,\mathrm{rr}\).

Looking at the phenotypes, we see a ratio of \(3\,\mathrm{red}:1\,\text{(whatever the recessive color is)}\). What does this tell you about the percentage of the offspring with red flowers?