Answer:
So that in a guinea pig cross in the offspring the recessive trait —long hair— can be observed in 25%, the most probable genotype of the parents is heterozygous Ss.
Explanation:
In guinea pigs, for the characteristic<u> hair length, short hair is the dominant allele and long hair is the recessive one</u>.
In order for 25% of the offspring to express the recessive characteristic, the parents must have a recessive genotype, which can be seen in Punnett's Square:
P: <u>Ss X Ss
</u>
<em>Alleles S s
</em>
<em>S SS Ss
</em>
<em>s Ss ss
</em>
Where the offspring is:
- <em>50% Ss with short hair phenotype
</em>
- <em>25% SS with short hair phenotype
</em>
- <em>25% ss whose phenotype would be long hair.
</em>
According to this, heterozygous parents for the characteristic long hair in guinea pigs have a 25% chance of having offspring with long hair.
There are multiple reasons. 1) there are similar fossils found on different continents. 2) the continents shapes show that they could easily fit together. 3) there are similar rocks, minerals,and land forms on different continents. 4) there's evidence that there was once lush vegetation in areas with extreme cold.
Assuming purple is dominant, the genotypes of the parents must be Pp and pp, such that half the progeny have the dominant allele (P_) and half have the recessive phenotype (pp) 25% possibility of white-flowered plant life and 75% possibility of pink ones
All living things have DNA within their cells
So Yes
Hope that helped