The differences between DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) can be summarized as follows:
1. **Strand Structure**:
- DNA is typically double-stranded, forming a double helix structure.
- RNA is usually single-stranded.
2. **Base Composition**:
- DNA contains the nitrogenous base thymine (T).
- RNA contains uracil (U) instead of thymine.
3. **Location**:
- DNA is primarily located in the nucleus of eukaryotic cells, although a small amount can be found in mitochondria and chloroplasts.
- RNA is found both in the nucleus and in the cytoplasm, where it plays various roles in protein synthesis.
4. **Building Blocks**:
- Both DNA and RNA are made of nucleotides, which consist of a sugar, a phosphate group, and a nitrogenous base. However, they differ in their sugars: DNA contains deoxyribose, while RNA contains ribose.
So, to correct the statements you provided:
- **DNA is double-stranded; RNA is single-stranded.**
- **DNA contains thymine; RNA contains uracil.**
- **DNA is found mostly in the nucleus; RNA is found in both the nucleus and the cytoplasm.**
- **Neither DNA nor RNA is made of amino acids; both are made of nucleotides.**
In summary, the correct differences are related to the structure, nitrogenous base composition, location, and the type of sugar present in the nucleotides.