What process was given as an example of the violation of Mendel's first law?

a. disjunction

b. nondisjunction

c. linkage

d. deletion

e. insertion

b. nondisjunction

Explanation:

During anaphase-I of meiosis-I, homologous chromosomes separate from each other and move to the opposite poles. During anaphase-II of meiosis-II, the sister chromatids move towards the opposite poles. Separation of chromosomes at anaphase is called disjunction.

When chromosomes do not segregate from each other, it is non-disjunction. Non-disjunction leads to the presence of both alleles of a gene in a gamete and violates Mendel's first law.

For example, the non-disjunction of chromosome 21 leads to the presence of both alleles of all the genes present on chromosome 21 in the same gamete.

According to Mendel's first law, each gamete carries only one allele for a gene. It is called as law of segregation.