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Mendel proposed a model to explain the results of a cross between pure-breeding

ID: 135931 • Letter: M

Question

Mendel proposed a model to explain the results of a cross between pure-breeding lines. What are pure-breeding lines?

1. A pure-breeding line is a group of individuals that always produce a 3:1 ratio of phenotype in their F1 generation.

2. A pure-breeding line is homozygous for the gene in question; when individuals of the same phenotype are crossed, they always produce the same phenotype.

3. A pure-breeding line is heterozygous for the gene in question and always generates a heterozygote in the F1 generation.

4. A pure-breeding line has two recessive alleles and never has a dominant allele.

Explanation / Answer

ANSWER - (2)

A group of genetically identical homozygous individuals that, when intercrossed, produce only offspring that are identical to their parents. SO, A pure-breeding line is homozygous for the gene in question; when individuals of the same phenotype are crossed, they always produce the same phenotype. If they are heterozygous, then they wont ptoduce same phenotypes as their parents have.