The bond that holds phosphates and sugars together in molecules like DNA and RNA is a phosphodiester bond.

Here's a breakdown:

* Phosphate: A phosphate group (PO₄³⁻) is an important component of nucleic acids.

* Sugar: In DNA, the sugar is deoxyribose, while in RNA, it is ribose.

* Bond Formation: The phosphate group forms a bond with the 5' carbon of one sugar molecule and the 3' carbon of another sugar molecule. This creates a strong and stable linkage called a phosphodiester bond.

Here's a simple analogy: Imagine a chain where each link consists of a sugar and a phosphate. The phosphodiester bond acts as the link connecting these sugars and phosphates to create the long chain of a DNA or RNA molecule.