One example that is not true according to Mendel's law and meiosis is the inheritance of multiple genes that are located very close to each other on the same chromosome.
Mendel's law of independent assortment states that different genes are inherited independently of each other during meiosis, which means that the distribution of alleles for one gene should not influence the distribution of alleles for another gene. This is true as long as the genes are located on different chromosomes or are located far apart from each other on the same chromosome.
However, if two genes are located very close to each other on the same chromosome, they are said to be in strong linkage disequilibrium. During meiosis, the two genes may be inherited together as a unit, and the frequency of certain allele combinations may deviate from the expected frequencies based on independent assortment. This violates Mendel's law of independent assortment.
Therefore, the inheritance of multiple genes that are located very close to each other on the same chromosome is not true according to Mendel's law and meiosis.