Final answer:
Nucleotides in RNA are connected by covalent bonds between sugar and phosphate.
Step-by-step explanation:
Nucleotides in RNA are connected to one another in the polynucleotide chain by covalent bonds between sugar and phosphate. The sugar molecule of one nucleotide binds to the phosphate group of the next nucleotide, forming a phosphodiester bond. These bonds create a strong backbone for the RNA molecule.