Inheritance topic questions

Question 1

Explain how Mendel used homozygous tall and homozygous short pea plants to show that tall allele is dominant to short allele(2)

Answer 1

Mendel crossed homozygous tall and homozygous short pea plants and they all produced tall offspring(1)

All the offspring had a heterozygous genotype with one tall and one short showing that tall is dominant(1)

Question 2

Explain how this showed that some inherited straits are not expressed in an organisim(3)

Answer 2

The first generation was hetrozygous(1)

Offspring needed two wrinkle allelles(1)

25 percent offsrping have wrinkled seeds(1)

Question 3

Explain how two parents with a dominant phenotype can produce offspring expressing a recessive charachteristic(2)

Answer 3

Both parents must be hetrozygous for the recessive allelle(1)

So the offspring must inherit the recessive alllellle from each parent(1)

Question 4

Explain how Greagor mendel could of used a brown drosphoria fruit fly and a black dysholia fruit fly to show that brown body colour is dominant to black body colour(6)

Answer 4

Cross the brown fruit fly and black fruit fly
Identify the phenotype of the offspring(1)
All the phenotype will be brown body
remove the parent flies
cross brown offspring
Identify