Is inheritance of acquired traits part lamarks theory?

Yes, inheritance of acquired traits is part of Lamarck's theory of evolution, also known as Lamarckism. Lamarck proposed that organisms can pass on to their offspring characteristics that they have acquired during their lifetime. For example, he believed that if a giraffe stretched its neck to reach leaves in tall trees, its offspring would inherit a longer neck. While this idea has been disproven by modern genetics, it was a significant contribution to evolutionary thought at the time.