Question

Mendel's Law is valid only when

• A. Two F${}_1$ hybrids are crossed.
• B. One parent is crossed with F${}_1$ hybrid.
• C. Two pure breeding contrasting characters are crossed.
• D. None of the above.

Answer 1

The correct option is C Two pure breeding contrasting characters are crossed.

Mendel's law is valid only when two pure breeding contrasting characters are crossed. In that case the dominant trait will be expressed in both homozygous and heterozygous conditions. Mendel's second law is only valid for genes located in different chromosomes. For genes situated in the same chromosome, i.e., linked genes the law is not valid since the segregation of these genes is not independent.