Answer: Like the thread, molecule of DNA is so thin, around 2 nm in length so, it cannot be seen with the naked eye. When DNA is clumped together, it is visible. To see or examine the DNA, it must be isolated from the cell and examine under microscope. Strands of DNA should be released from the nuclei of the cell and should be separated from other components such as histone protein around which it is coiled, before examining it.