To determine which options represent nucleotides in RNA, we need to understand the basic structure of RNA nucleotides. An RNA nucleotide comprises three components: a phosphate group, a sugar (ribose in the case of RNA), and a nitrogenous base.
Among the choices provided:
- Phosphate sugar adenine: This represents an RNA nucleotide since it includes the phosphate group, ribose sugar, and adenine as the nitrogenous base.
- Phosphate sugar uracil: This is also valid as uracil is another nitrogenous base found in RNA, replacing thymine, which is found in DNA.
- Phosphate sugar thymine: Thymine is not used in RNA; instead, uracil takes its place. Therefore, this option does not represent an RNA nucleotide.
Consequently, the correct answers are the first and second options, which accurately reflect the components of RNA nucleotides.