Final answer:
Non-Mendelian inheritance refers to the inheritance patterns that do not align with Mendel's laws of inheritance, involving complex genetic bases like codominance, incomplete dominance, and polygenic inheritance, which often result in a blending of traits.
Step-by-step explanation:
Inheritance of traits transmitted by mechanisms not involved in the nucleotide sequence is called non-Mendelian inheritance. This term encompasses several complex mechanisms of inheritance which do not follow the traditional Mendelian pattern where traits are determined by single genes with two alleles and complete dominance.
Non-Mendelian inheritance includes patterns such as codominance, incomplete dominance, and polygenic inheritance, among others. An example of non-Mendelian inheritance is the inheritance of human blood types, where the ABO blood groups demonstrate both codominance and multiple alleles, and traits like skin color are influenced by multiple genes (polygenic), illustrating that traits can have a more complicated genetic basis than Mendelian simple dominance.