Question

True breeding line is ___.

• A. homozygous
• B. heterozygous
• C. hemizygous
• D. isozygous

Answer 1

The correct option is A

homozygous

True breeding line is produced due to continuous self-pollination. Continuous self-pollination increases homozygosity and the traits are passed stably from one generation to another.
Hybrids are heterozygous, that is having the genes for two different traits, although only the dominant trait is expressed.
A chromosome in a diploid organism is hemizygous when only one copy is present. The cell or organism is called a hemizygote. Hemizygosity is also observed when one copy of a gene is deleted, or in the heterogametic sex when a gene is located on a sex chromosome. For eg. the genes on the Y-chromosome in humans.
Isogenic are organisms having the same genotype.