Answer: The correct answer is -
Chromosome and genes.
Chromosomes are the thread like twisted structured composed of the genetic material (DNA, deoxyribonucleic acid).
They possess heredity units called genes (segment of DNA, which determines particular trait of an organism). These units are passed from one generation to the next generation through chromosome.
Genes are transcribed and translated to form particular protein, which depicts anatomical feature of an organism.
Therefore, similarities in anatomical features/structure among different organisms is because of chromosomes and genes present in the organism.
