The molecule that carries genetic information from the nucleus to the ribosome is messenger RNA (mRNA).

Here's how it works:

1. Transcription: DNA in the nucleus is transcribed into mRNA. This means the genetic code from DNA is copied into a messenger molecule.

2. mRNA Processing: The mRNA undergoes some modifications to prepare it for translation.

3. Export: The processed mRNA leaves the nucleus and enters the cytoplasm.

4. Translation: The mRNA arrives at a ribosome. Here, the genetic code is translated into a chain of amino acids, forming a protein.

So, mRNA acts as a go-between, carrying the genetic instructions from the DNA in the nucleus to the protein-making machinery in the ribosome.