DNA is wound up tight in structures called these. chromosomes nucleic acids chromateres

## Step 1<br />The question is asking for the name of the structure in which DNA is tightly wound up. The options provided are chromosomes, nucleic acids, and chromateres.<br /><br />## Step 2<br />DNA is tightly wound up in structures called chromosomes. Chromosomes are thread-like structures located inside the nucleus of animal and plant cells. Each chromosome is made of protein and a single molecule of DNA. <br /><br />## Step 3<br />The term "nucleic acids" refers to the macromolecules DNA and RNA, which are the molecules that carry genetic information. <br /><br />## Step 4<br />"Chromateres" is not a recognized term in biology. <br /><br />## Step 5<br />Therefore, the correct answer is "chromosomes".